The Official AVS Antenna Topic! [Text View] - Page 15

rwantennasat

12-18-05, 12:56 PM

I've done extensive testing with the Winegard PR-9032. It's inferior when used as a single antenna or a stack vs. the Televes DAT 75 pretty much up and down the band. The CM 4228 also outperformed the PR-9032 for me. The XG91 is a clone of the Funke 91 element model and MaxHD would tell you the Funke 91 element is at least comparable to the DAT 75. The Winegard 8200p combo is significantly inferior (for uhf) in performance to any of the above mentioned uhf antennas.

Winegard is notorious for exaggerating their numbers for antenna performance.
I'd still say they're a good value, but you get what you pay for.

Thats very odd Guess it goes to show what differences their are in dif locations. I've always seen a better gain on the 9032 vs the 4228. even over average terrain. EX: on my house roof i have a 10 ft tripod with a big vhf log then 10' above the 9032 and a ap4700. it see's more than the 4228 did with same amp and height?? However the Televes antennas are not all that reasonable. For the gain dif a low noise amp would probably make it up. Again I'll always say theirs noting like a parabolic. I'll be sending some photo attachments of my array's
Rich LOckport N.Y.

rwantennasat

12-18-05, 01:04 PM

What are you going to use to combine the 4 8-bays?

How about a pic of the custom parabolic,and what feed did you use?

here is a photo of what a 7' parabolic can do from Lockport,N.Y. 14094 1200 miles

rwantennasat

12-18-05, 01:36 PM

I've done extensive testing with the Winegard PR-9032. It's inferior when used as a single antenna or a stack vs. the Televes DAT 75 pretty much up and down the band. The CM 4228 also outperformed the PR-9032 for me. The XG91 is a clone of the Funke 91 element model and MaxHD would tell you the Funke 91 element is at least comparable to the DAT 75. The Winegard 8200p combo is significantly inferior (for uhf) in performance to any of the above mentioned uhf antennas.

Winegard is notorious for exaggerating their numbers for antenna performance.
I'd still say they're a good value, but you get what you pay for.
some photos of my arrays
fisrt is 7 ' parabolic on 80' tower w/ winegard ac-4990 preamp
2nd is stacked hi band yagi's with a winegard 7-13 preamp ac-7130
3rd is a 7' finco on a 50 ft tower at 20' with winegard cp-4700
4th modified 9032 yagi(longer and bigger reflector) w winegard cp-4700 anda TDP vhf log apx 192" with a winegard ac-2880 vhf amp. at 30 ft

rwantennasat

12-18-05, 01:37 PM

some photos of my arrays
fisrt is 7 ' parabolic on 80' tower w/ winegard ac-4990 preamp
2nd is stacked hi band yagi's with a winegard 7-13 preamp ac-7130
3rd is a 7' finco on a 50 ft tower at 20' with winegard cp-4700
4th modified 9032 yagi(longer and bigger reflector) w winegard cp-4700 anda TDP vhf log apx 192" with a winegard ac-2880 vhf amp. at 30 ft

Ok here is photo 4

rwantennasat

12-18-05, 01:58 PM

I've done extensive testing with the Winegard PR-9032. It's inferior when used as a single antenna or a stack vs. the Televes DAT 75 pretty much up and down the band. The CM 4228 also outperformed the PR-9032 for me. The XG91 is a clone of the Funke 91 element model and MaxHD would tell you the Funke 91 element is at least comparable to the DAT 75. The Winegard 8200p combo is significantly inferior (for uhf) in performance to any of the above mentioned uhf antennas.

Winegard is notorious for exaggerating their numbers for antenna performance.
I'd still say they're a good value, but you get what you pay for.

Here is a gain chart for the DAt-75 # D and the 9032 #N and the difference is negligeable at the bands beggining. It DAT75 does show a bit more at band middle and end. But we dont go above ch 69 here. The author of tis also went on to show the actual gain and most antennas would suprise you!!!!! He did a section on The DAt-75 stating how its gorssly overated by the European Builders?
So As i said before Its all about what works for you BUt nothing will beat a PArabolic Anywhere!!!!!
Rich

ctdish

12-18-05, 01:59 PM

The Quad Cm2228s will have separate downleads each connected to their respective 7775 Power Supply. From there the options are many.... Single..dual.... horiz...vert... etc.... PicoMacom TSB-41GFR Premium 4-Way splitter w/130DB isolation would be sufficient for a 4-way combiner. Unused inputs (if i am using a 2 antenna array) would be terminated.

The parabolic is up about 110ft.. The feed for it is essentially a log periodic...

You need to have the down leads exactly the same length because the signals have to be in phase when they are added in the combiner. Also you have to be careful to get the phase correct when hooking up the 300/75 ohm balun or again the signals will cancel rather than add when combined. The splitter loss will not matter much since you are combining after the preamps.
I use four combined 4248 antennas with a 0.4 dB preamp and a stripline combiner. They are up only about 45 feet though. John

AntAltMike

12-18-05, 02:59 PM

The Quad Cm2228s (4228s?) will have separate downleads each connected to their respective 7775 Power Supply. From there the options are many.... Single..dual.... horiz...vert... etc.... PicoMacom TSB-41GFR Premium 4-Way splitter w/130DB isolation would be sufficient for a 4-way combiner.

You are pre-amplifying them individually, before combining? I'm not even sure that would improve your S/N ratio, because you'd be adding the noise of the four preamps. Four times as much signal, four times as much preamp noise...

The splitters don't have 130dB of isolation. They have 130dB of RF shielding, because the backs of their cases are soldered on rather than glued on. That factor is only important to those who are concerned that they will be inadvertently broadcasting their signal.

A four-way splitter will not work very well for a quad. Three cheap 2-way splitters will work better. A stripline combiner is the best thing to use..link..

I agree, Then you will need to use only one preamp.

By the way, I once compared the insertion loss of a pair of back-to-back Channel Master outdoor baluns with their indoor ones, and believe it or not, the cheap, indoor ones only typically lost an average of less than 1dB at UHF frequencies, varying from about 1/2 to 1.5dB at various channel frequencies, whereas the insertion loss of the outdoor ones varied from 1/2 dB to about 4dB at different channels. Honest!. But I don't think the indoor ones are labeled for polarity, so you might have to do some experimenting to get them to work in unison.

Channel Master and Winegard must have made some old, low-loss 300 ohm antenna combiners. If they did, and if you can get your hands on any, they may be a good value and solution for your combining needs.

As I recall, the HDTV Primer site has criticized the impedance match of the 8-bay bowtie. It is easy to get a 4-bay 300 ohm array to combine to 300 ohms, since putting two in parallel results in 150 ohms, and then connecting those two pairs in series brings the load back to 300 ohms, but there is no simple way to do that with the 8 bays, though I suppose if sufficient thought and know-how went into the engineering of the coupling rails, some kind of compensation might have been engineered into them.

If were building this monstrosity,I might be tempted to construct two pair of vertical rails between the upper and lower antennas and then horizontally combining them from their vertical midpoints, using construction like the coupling busses used to connect the individual bowties and stacks in each antenna and see what you get for performance

Tower Guy

12-18-05, 03:24 PM

The noise figure on the Winegard preamps is 2.7dB for UHF, while the Channel Masters are 2.0. As others have posted here, there are preamplifiers with 0.4dB of noise. According to the experts, S/N only improves when the noise figure is 2.0dB or lower. The Winegards are better at handling overload than the Channel Masters, which may explain your testing results. I have a Winegard myself, and I'm not saying they're bad.

The advantage due to amplifier noise figures is different for a TV antenna than for a satellite LNB. This is because the satellite antenna is aimed up, away from the earth. The noise temperature of the sky varies from 4 degres Kelvin for deep space to about 35 degrees Kelvin into the Milky way. The noise temperture when aimed at the horizon is the actual temperture of the earth. It is is often approximated as 273 degrees Kelvin, but that's really only true at 32 degrees farenheit. In any event, a noise temperature of 273 equates to a noise figure of about 3 db. Unless there's excessive loss in the balun or a long coax betwen the antenna and the preamp, the difference between a noise figure of 2.0 and 2.7 db is immaterial for OTA reception.

Tower Guy

12-18-05, 04:28 PM

Could anyone help me with following questions?

Is getting too much digital singal strength a bad thing?
What are some of the symptoms of very strong digital signals?

I was told I should install an attenuator and connect it to my OTA antenna.

Thanks

Too much signal can overload the TV. Normally it's hard to overload a TV, but it's easier to overload a preamplifier.

I can overload my Zenith TV set when I use an all channel antenna. I am 8 miles from the transmitters in Albany. There's nothing in the way to attenuate the signals. In my case a strong channel ch 6 analog (82-88 mhz) caused intermod 14 channels below channel 45, a full power UHF analog. Center of channel 45 minus center of channel 6 equals channel 31, a classic third order intermod product. This prevented me from receiving a channel 31 in Hartford. The use of a Winegard UHF only preamp (VHF pass) did not help. I replaced the all-channel antenna with a 4228 Channel Master UHF only, and the problem was much better, but not completely gone. Finally, I built a 3 pole interdigital filter for channel 31. Here's what I used to design it.
http://www.wa4dsy.net/cgi-bin/idbpf

Tower Guy

12-18-05, 04:39 PM

What can be done with stations that multicast?

Thanks

Multicasting looks bad when fixed bit rate encoding is used. Variable bit rate is much better, approaching the PQ of no multicasting. If your local station is using fixed bit rate, tell them to buy these for Christmas;

http://www.tandbergtv.com/productview.asp?n=41
http://www.tandbergtv.com/productview.asp?n=51
http://www.tandbergtv.com/productview.asp?n=52

Harmonic also makes similar products.

http://www.harmonicinc.com/view_csd_product_group.cfm?classID=2374

They should expect to pay almost $100K to do it right. That's not in my Christmas budget this year.

Tower Guy

12-18-05, 04:42 PM

Originally Posted by sregener
Generally speaking, an outdoor antenna will lose at least 50% of its performance over 10 years due to corrosion.

Sorry, but that sounds like BS. Can you provide a link or other explanation?

Ron

He must be talking about RatShack antennas.

cpcat

12-18-05, 05:14 PM

Here is a gain chart for the DAt-75 # D and the 9032 #N and the difference is negligeable at the bands beggining. It DAT75 does show a bit more at band middle and end. But we dont go above ch 69 here. The author of tis also went on to show the actual gain and most antennas would suprise you!!!!! He did a section on The DAt-75 stating how its gorssly overated by the European Builders?
So As i said before Its all about what works for you BUt nothing will beat a PArabolic Anywhere!!!!!
Rich

Well, like I said, I've tried them both at my location and the DAT 75 performed better without doubt. Gain charts are of some value, but it's actual performance that counts. The HDTVprimer link you gave is actually very complimentary of the DAT 75 if you read it all.

Your 1200 mile tropo catch is nice and those are some cool rigs you've put up. :) I got a station from Havana via e-skip once on a simple channel 4 folded dipole.

It's hard to argue with the gain a parabolic can produce. The disadvantages come from size, weight, wind and rotor loading as well as less front/back ratio.
I've heard of folks adding screening to them which I'm sure helps but then that adds even more weight and load.

I'd still like to try one. I'll be glad to beta test for you if you like.

firemantom26

12-18-05, 05:41 PM

I thought you guys/gals might enjoy seeing some pictures of an antenna project my partner and i are working on. We currently have a self-designed parabolic up approx. 100' on a R25G tower with a Yaesu 800 rotor. The new project is a Quad CM 2228 that is modified to improve feed design and will consist of 4 (32 Bay total) 4228s each with 7775 preamps. A BT BTY-HB-HP Hi-band VHF with a CM7777 will be below the bowties and will handle the VHF duties. On the UHF side, the 4 CM 2228 (Modified) each with 7775 Amps .. will have individual 7916 Belden downleads. This way we can stack in any manner we wish, by simple selecting the desired antenna(s) Performance was excellent on the parabolic and we are optimistic that this will exceed it.... We consistently lock on HD stations 100-175 miles. When we get this up, maybe i can share some data with you. Happy Holidays from East Texas.....

I think the route I am going with is stacking two CM- 4228 Do you know how much DB gain this will make?
Also to go stack vertical or horizontal? I have Samsung 26" HDTV (TX-P2675WHD) Channel Master 4228 UHF antenna Channel Master 777 amp and a Channel Master rotator( CM 9521A)

TotallyPreWired

12-18-05, 06:51 PM

I think the route I am going with is stacking two CM- 4228 Do you know how much DB gain this will make?
Also to go stack vertical or horizontal? I have Samsung 26" HDTV (TX-P2675WHD) Channel Master 4228 UHF antenna Channel Master 777 amp and a Channel Master rotator( CM 9521A)
Most of the answers you desire are here. (http://www.hdtvprimer.com/ANTENNAS/16bay.html)

There is also a section for 32 bay antennas. :p
....jc

AntAltMike

12-18-05, 09:32 PM

I think the route I am going with is stacking two CM- 4228 Do you know how much DB gain this will make?
Also to go stack vertical or horizontal? I have Samsung 26" HDTV (TX-P2675WHD) Channel Master 4228 UHF antenna Channel Master 777 amp and a Channel Master rotator( CM 9521A)

Why do you suspect that a slight improvement in the quality of your antenna signal will be beneficial? What stations are you having trouble with?

billinabnett

12-18-05, 10:02 PM

Thanks for the input on the Quad CM2228s. Frankly, we feel that the 4 way splitter (PicoMacom- used as a combiner) is sufficient due to it providing a 75ohm match to the output of each 7775. Also each amp is pushing 25-26 db gain into each port. Our concept was to not focus on one method of stacking. If lower NFs are needed, i have the .4 NF amps from Europe... but they are 20db gain and the CM7775 is more gain. It is our opinion that more signal is lost due to ineffective matching with stacking schemes, spacing, etc. Please don't think i am ignoring theory, but i prefer to experiment and obtain the best solution.. I would throw this out for comment also.. 300-75 conversion at the feed is my preference. Also, i feel it is critical to have the bottom mesh of the top 4228s overlap the top mesh of the bottom 2 CM4228s. This way all of the 8 vertical bowties (in a vertical line) have the same vertical spacing between them. Also, i think it makes sense to use black (UV Protected) tiewraps to tightly secure all sections of the mesh, thus giving a contiguous mesh. Also, using corrosion proof materials on the feeds (balun connect points) and then good sealing. Happy Holidays!!

firemantom26

12-18-05, 10:11 PM

Why do you suspect that a slight improvement in the quality of your antenna signal will be beneficial? What stations are you having trouble with?

A couple from Pittsburgh are hit and miss.

sebenste

12-19-05, 12:06 AM

Gilbert,
You didn't say what antenna you're using to receive Ch3?

My experience using preamps on Lowband is "not much difference".In your situation,a cut-to-channel 3 antenna placed somewhere for the best possible signal,would be the best you could do.
I have an old no-longer-manufactured Winegard VHF-only antenna (channels 2-13). It's huge and it barely fits in my attic. It's like 17' long.

Gilbert

sebenste

12-19-05, 12:08 AM

No typo. The FCC has made it abundantly clear that they will grant a one-time, six month extension for stations unable to get to full power by 7/1/06 if there are extenuating circumstances. Given their willingness to grant those to the big 4 in top-30 markets on 7/1/05, I gave the conservative date when they'll need to be close to full power (minimum 85% market coverage, based on 1999 census data.)
Sregener,

And that's the key...extenuating circumstances. I understand the FCC was not happy about it. I wonder if they will be less generous in this round?

sriggins

12-19-05, 02:07 AM

Hi :) I have an internal antenna ( http://www.geeksrus.com/albums/livinginoregon/Pages/CRW_3075.html ) that I moved into a empty bedroom and now have reception on all channels except for 2-1 (43) KATU here in Portland.

Is there any chance I can get all channels? In the pic above, I had all channels but 8-1 (46) NBC. Will a pre-amp help at all or will it just amplify the data that is missing the start with.

I'm renting and will be buying, and also hoping for the channels to move to the sat some day, so don't want to invest in an outdoor solution right now.

When I am not getting a channel, the signal bounces from say 88 to 17 etc etc, like it does on 2-1 now.

I bought a compass and think it is pointed in the general 64 degree direction (63 for 2-1, 6-1, 68 for 8-1) From what i have read, 6-1 and 2-1 share the same tower. I get 6-1 fine.

thanks!

sregener

12-19-05, 09:15 AM

And that's the key...extenuating circumstances. I understand the FCC was not happy about it. I wonder if they will be less generous in this round?

Technically, it's the same round. The 100% power (or 85% of 1999 population coverage if not retaining the digital channel allocation at analog shutdown) requirement is phased in based on market size and station "importance." The deadline for the big 4 (ABC, NBC, CBS and Fox but oddly not PBS) in the top-100 markets was 7/1/05. Many stations missed the deadline. The FCC granted extentions to all but one station that requested it, and they denied the one in part because the station didn't submit their extension request until after the deadline had passed. Their punishment consisted in a pretty hefty fine, and that was all.

The second half of the 100% requirement comes due on 7/1/06, which includes all stations in the country. Note that extensions are still available for "financial hardship," meaning that stations that would be bankrupted by the expense of going full power are not subject to this deadline - at all. They don't need a special, one-time six month extension. They could, if needed, wait until the analog shutdown to flash cut to digital. WEUX/WLAX in Eau Claire/La Crosse, WI is a perfect example. For stations that cannot demonstrate financial hardship, six month extensions shouldn't be too hard to come by, especially for stations that require tower work. Because of all the stations that have tower work, the limited number of tower crews is stretched to the limit. Backlogs are months, if not years, long. Having existing towers knocked down by weather and wayward airplanes hasn't helped this much.

It is not in the FCC's or the public's interest for stations to lose their interference protected areas, and I think only the most extreme cases will see penalties like this. As long as the stations have put forth a good-faith effort in getting their digital signals ramped up, I don't forsee the FCC denying extensions. While this is frustrating for us, the viewers, the long-term impact of, say, an ABC affiliate permanently locked at 6kw would be far greater than the short-term cost of a six-month extension.

While I hope that all stations meet the 7/1/06 deadline, I have learned never to promise results to people hoping for a particular station on such tenuous legal requirements. The real date is 12/31/06 for all intents and purposes, and I suspect that most stations will be near full power.

It is worth noting that the "full power" requirement lacks a lot of teeth for stations reverting to their analog (or a completely different) frequency; the 85% requirement is based on 1999 census data. Thus, a station like KSTC-DT in Minneapolis/St. Paul is reaching the number of viewers that they reached in 1999 with a 205kw signal, due to population growth. If they had to cover the area they had in 1999, they would be much closer to 500kw. The difference in range between 500kw and 1000kw is very small.

sregener

12-19-05, 09:23 AM

Here is a gain chart for the DAt-75 # D and the 9032 #N and the difference is negligeable at the bands beggining. It DAT75 does show a bit more at band middle and end. But we dont go above ch 69 here. The author of tis also went on to show the actual gain and most antennas would suprise you!!!!! He did a section on The DAt-75 stating how its gorssly overated by the European Builders?

At the beginning of the UHF band, all these yagi/corner-hybrid models are basically simple corner reflectors. The differences are going to be subtle at best. At the middle of the band, you start to see the benefits of the yagi designs. And while the 9032 does catch up as you pass channel 60, this will be academic in a few years when the broadcast spectrum in the US drops to channel 51. For those in border zones getting Canadian stations, performance at the higher channels may matter. I find the flat gain across the middle channels (say, around channel 40) to be particularly damning of this antenna.

I'm not defending the DAT 75 or any other model, or the gain figures advertised. People have done everything they can to make their model look the best, including some pretty weird testing standards. But just because a claim is exaggerated doesn't mean the antenna doesn't perform. The DAT 75 is still a top performer, though maybe not quite as good as the manufacturer would have you believe.

The 4251 is a great antenna for what it does, but at least one tester found it inferior to many other antennas: http://www.atechfabrication.com/tests/04-24-01_test_results.htm

His conclusion? "4251 best long distance capability, but not good for multipath." And we all know that multipath can kill digital reception.

sregener

12-19-05, 09:27 AM

Will a pre-amp help at all or will it just amplify the data that is missing the start with.

An amplifier is unlikely to help you in your situation. The bouncing signal is almost always an indication of multipath. You could check analog UHF signals from the same tower and see if your reception is ghosty or snowy. If it has ghosts, an amplifier isn't going to help. If it's snow, then it's worth a shot. If you do have ghosts, you may actually want to try a variable attenuator from Radio Shack. It has helped some people deal with multipath (which looks like ghosting on analog signals.) If it doesn't work, you can always return it for a full refund.

MAX HD

12-19-05, 09:41 AM

cpcat

12-19-05, 09:47 AM

rgathright

12-19-05, 11:18 AM

This is off thread, but this is the best place to get help. I have 2 homes due to Hurricane Katrina. All of my HDTV's are in the Houston rental. I have a new house in Louisiana that I visit 2 times a month. I need a good VHF antenna that will pull in the local VHF OTA signals. I already have a CM4228 for the UHF stations, but need something that will pull in the VHF stations. I tried my best to talk the wife into getting a third HDTV, but she has not agreed yet. In the meantime I need to pull the local analog stations. Antennaweb shows all of the analog stations to be blue and violet.

Any help is appreciated.

sregener

12-19-05, 11:54 AM

I need a good VHF antenna that will pull in the local VHF OTA signals.

Can't go wrong with the biggest combos Winegard and Channel Master make. If you're not using a preamp with separate inputs, the Channel Master #0549 will filter out the UHF from the combo.

If you want to spend some real cash on VHF, you can get a Delhi VHF-only for around $200.

Winegard also makes 3 VHF-only antennas, the PR5020, HD4053 and PR5030. Any of them should work fairly well for you.

sebenste

12-19-05, 03:10 PM

Technically, it's the same round. The 100% power (or 85% of 1999 population coverage if not retaining the digital channel allocation at analog shutdown) requirement is phased in based on market size and station "importance." The deadline for the big 4 (ABC, NBC, CBS and Fox but oddly not PBS) in the top-100 markets was 7/1/05. Many stations missed the deadline. The FCC granted extentions to all but one station that requested it, and they denied the one in part because the station didn't submit their extension request until after the deadline had passed. Their punishment consisted in a pretty hefty fine, and that was all.

The second half of the 100% requirement comes due on 7/1/06, which includes all stations in the country. Note that extensions are still available for "financial hardship," meaning that stations that would be bankrupted by the expense of going full power are not subject to this deadline - at all. They don't need a special, one-time six month extension. They could, if needed, wait until the analog shutdown to flash cut to digital. WEUX/WLAX in Eau Claire/La Crosse, WI is a perfect example. Backlogs are months, if not years, long. Having existing towers knocked down by weather and wayward airplanes hasn't helped this much.

It is not in the FCC's or the public's interest for stations to lose their interference protected areas, and I think only the most extreme cases will see penalties like this. As long as the stations have put forth a good-faith effort in getting their digital signals ramped up, I don't forsee the FCC denying extensions. While this is frustrating for us, the viewers, the long-term impact of, say, an ABC affiliate permanently locked at 6kw would be far greater than the short-term cost of a six-month extension.

While I hope that all stations meet the 7/1/06 deadline, I have learned never to promise results to people hoping for a particular station on such tenuous legal requirements. The real date is 12/31/06 for all intents and purposes, and I suspect that most stations will be near full power.

Sregener,

Great post and comments. However, the FCC may not be as generous to those who have the money and were just being "lazy". But given your point, you're right, the FCC will probably grant the 6-month extension. WCIA-DT in Champaign, IL is probably one example. They told viewers they'll be up "by the end of 2006"
to full power and HD. It can also be noted that the FCC was slow in approving their CP.

Whatever the case may be, 2006 will feature, in general, the second-to-last stage of the DTV transition. 2009, when it comes, will finally yank analog cell phones, TV's and other devices off the hook forever (unless you have a converter box, of course).

Can't happen soon enough for me! And I can't even afford cable or satellite right now, just over-the-air DTV.

sregener

12-19-05, 04:28 PM

Can't happen soon enough for me! And I can't even afford cable or satellite right now, just over-the-air DTV.

I'm not in the camp looking forward to the analog shutdown. I figure to lose more than I'll gain.

Four distant (55+ miles) stations will revert to hi-VHF, but their distance and local interference mean I probably won't get a usable signal from any of them.

One station will go from a limited power (but covering 85%) and low transmitter location to high power and the top of their tower, so I'll gain them.

Another station will drop their temporary, 205kw signal (still covering 85%) and go to a full megawatt, but I get them just fine now most of the time, and the times I don't, other 1000kw stations don't come in so I have reason to expect them to be better.

That's about it. Lose 4. Gain (maybe) 2.

I also use analog coverage of distant stations when the digital stuff isn't coming in, even full powered digital stations. Those will be gone, as well. No analog backup when digital reception over the horizon isn't all it could be.

Troubleshooting digital reception will be harder, as most tuners give no indication as to why a signal is breaking up other than useless information like "85%" and "52%".

What's the thrill? The full-power deadline is the one that I'm looking forward to. The analog shutoff? Only the broadcasters seem to benefit from that.

deconvolver

12-19-05, 04:57 PM

What's the thrill? The full-power deadline is the one that I'm looking forward to. The analog shutoff? Only the broadcasters seem to benefit from that.
Here in the northeast of the country where overcrowding of the airwaves is a real problem the analog shutdown should help with interference issues. It will really make troubleshooting reception issues a lot more difficult though.

milehighmike

12-19-05, 05:21 PM

Quote from sebenste:

While I hope that all stations meet the 7/1/06 deadline, I have learned never to promise results to people hoping for a particular station on such tenuous legal requirements. The real date is 12/31/06 for all intents and purposes, and I suspect that most stations will be near full power.

In the Denver DMA, your last sentence would read: "There is no real date and for all intents and purposes no stations will be near or at full power in the foreseeable future."

sregener

12-19-05, 05:26 PM

In the Denver DMA, your last sentence would read: "There is no real date and for all intents and purposes no stations will be near or at full power in the foreseeable future."

I think once Congress approves a tinfoil-hat subsidy for all residents of Denver and surrounding community, as well as special glasses that make broadcast towers appear invisible, Denver will join the digital fold. Until then, the NIMBYs and NINCOMPOOPS will prevail.

newsposter

12-19-05, 07:19 PM

No typo. The FCC has made it abundantly clear that they will grant a one-time, six month extension for stations unable to get to full power by 7/1/06 if there are extenuating circumstances. Given their willingness to grant those to the big 4 in top-30 markets on 7/1/05, I gave the conservative date when they'll need to be close to full power (minimum 85% market coverage, based on 1999 census data.)

this post interests me GREATLY. I'm in a topographically challenged (ok neighbors house in the way) area and my fox station at 2 degrees off every other channel is low on wattage. Also WB at channel 54 is low power and 67NBC just gets goofy at times. If these channels Must up their power next year, this would help me a lot

So in the Philly area will this happen?

sebenste

12-20-05, 12:44 AM

I think once Congress approves a tinfoil-hat subsidy for all residents of Denver and surrounding community, as well as special glasses that make broadcast towers appear invisible, Denver will join the digital fold. Until then, the NIMBYs and NINCOMPOOPS will prevail.

LOL! OK, not for you folks in Denver. I forgot about that market. I haven't read through all the posts and articles so I hope they're not worried about a few skunks being nuked. If they're using the same broadcast towers, sheesh, they go from 5 million watts ERP to 1 million max. That means they drop 80% of the ERP pwer, and obviously a very significant amount of actual electricity as well.

Unreal.

Sregener: VHF-Hi is probably best without interference. Are you talking about electrical interference/atmospherics or multipath? If multipath, you'd be better off with a parabolic dish. I wish stations would just go 2000' with their towers
and 1 million watts instead of 1,000' or 1,500'. Then again, sadly, they typically don't care about rural listeners. Being one 60 miles west of Chicago, I sympathize with that one.

As for the northeastern U.S.: Absolutely. A ton of interference will go away, but definitely not all after analog shutdown.

billinabnett

12-20-05, 01:58 AM

Yes Max, there is an amp for each 8-bay antenna... but remember due to modifying the feeds and removing the center part of the antenna, i have used a 300-75 balun at the center of each 4-bay section. Then with exactly equal lengths out of the balun, these feed a 2-way combiner which then feeds the amp. Thus placing a 75 ohm match to the balun. In the total quad setup, there is 8 baluns (Each 2 feeding a 2-way combiner and then feeding a 7775.

billinabnett

12-20-05, 02:11 AM

I agree about the phasing aspects CPCAT. If i need the low loss combiner, i will get one. I have currently a 2 way UHF one from Lindsay and will see if that is beneficial.. I am not convinced that will be needed considering each leg of the combiner is the output of the amp. Also, the downleads will all be equal in length.... Also, i use the Spectrum Analyser and insure the levels hitting the inputs match as closely as possible. All of that as previously been considered in our plans.
Thanks for the input.

sregener

12-20-05, 08:01 AM

this post interests me GREATLY. I'm in a topographically challenged (ok neighbors house in the way) area and my fox station at 2 degrees off every other channel is low on wattage. Also WB at channel 54 is low power and 67NBC just gets goofy at times. If these channels Must up their power next year, this would help me a lot

So in the Philly area will this happen?

Philadelphia is in the top-10 markets, and all major networks (including NBC, but not WB) were required to be full powered a few years back; the 7/1/05 deadline was a last-ditch, last minute deal. Those stations are probably already maximized (check your local thread for confirmation) due to interference protection in the crowded NE. I wouldn't look for any dramatic improvements from the big 4 until the analog shutdown.

The FCC shows WPHL-DT as being full-powered (i.e. licensed) at 500kw, although depending on your direction it could be half of that because they have chosen not to blast a strong signal to the W and NE. Still, with a good setup and some luck, you shouldn't have any trouble getting a 250kw station at 50 miles.

sregener

12-20-05, 08:02 AM

Sregener: VHF-Hi is probably best without interference. Are you talking about electrical interference/atmospherics or multipath? If multipath, you'd be better off with a parabolic dish.

Electrical interference? Check. FM interference? Check. Multipath? Nope.

Parabolic dishes suck for directionality. Really, truly, they do.

MAX HD

12-20-05, 10:47 AM

sebenste

12-20-05, 11:04 AM

Electrical interference? Check. FM interference? Check. Multipath? Nope.

Parabolic dishes suck for directionality. Really, truly, they do.

FM interference, FM trap. I'm 2 miles from a 20 kw FM. I have to trap them out.

Electrical? Where is it coming from? If it's the power company, they are violating FCC rules. Call 'em on it!

Parabolics suck for directionality? Then how do they achieve such an awesome gain? Directionality and gain go hand-in-hand, pretty much.

MAX HD

12-20-05, 11:08 AM

Parabolic dishes suck for directionality. Really, truly, they do.

Well,not altogether true.They have very good directionality in the direction they're pointed,with a very deep null a few degrees on either side of the main gain lobe.With a solid reflector to block signals off the backside,they would be great,but we all know what problems that would create.

sregener

12-20-05, 11:48 AM

FM interference, FM trap. I'm 2 miles from a 20 kw FM. I have to trap them out.

Electrical? Where is it coming from? If it's the power company, they are violating FCC rules. Call 'em on it!

Parabolics suck for directionality? Then how do they achieve such an awesome gain? Directionality and gain go hand-in-hand, pretty much.

Got the FM trap. Still penetrating. Strongly. Pointing the antenna in some directions, I can listen to classical music on Channel 8. But they're not the only problem station, since I've got the same interference on channel 9.

Electrical interference is really hard to track down, but I've got it in spades. I see "sparklies" consistent with impulse noise all the way up to channel 45 on analog signals. According to the installer, my entire city is blanketed in it. Some of it is from those invisible fences. Some is from noisy appliances like microwaves and refrigerators. Some of it is undoubtably from the power company themselves, but trying to get that resolved is a black hole - the FCC won't do anything, the power company "can't find any problems," the city owns the power company, and so it goes. On rainy days, though, it sometimes completely disappears.

Parabolics are very directional in the direction they are aimed. However, they have very poor front-to-back ratios when compared to other systems, undoubtably due to their porous screens and the fact that their active element is "aimed" backwards. They also accept multipath from a wide range, making them a horrible choice for most digital tuners.

rgathright

12-20-05, 02:07 PM

What would be causing "dots" to be running across my screen with my antenna? I know FM interferance is herringbone shaped. This happens on my lower (4 & 6) stations.

sebenste

12-20-05, 02:15 PM

Got the FM trap. Still penetrating. Strongly. Pointing the antenna in some directions, I can listen to classical music on Channel 8. But they're not the only problem station, since I've got the same interference on channel 9.

Electrical interference is really hard to track down, but I've got it in spades. I see "sparklies" consistent with impulse noise all the way up to channel 45 on analog signals. According to the installer, my entire city is blanketed in it. Some of it is from those invisible fences. Some is from noisy appliances like microwaves and refrigerators. Some of it is undoubtably from the power company themselves, but trying to get that resolved is a black hole - the FCC won't do anything, the power company "can't find any problems," the city owns the power company, and so it goes. On rainy days, though, it sometimes completely disappears.

Parabolics are very directional in the direction they are aimed. However, they have very poor front-to-back ratios when compared to other systems, undoubtably due to their porous screens and the fact that their active element is "aimed" backwards. They also accept multipath from a wide range, making them a horrible choice for most digital tuners.

Sregener,

Time for the heavy artillery. Quad-shielded RG-6 and a 50dB FM trap
(or maybe two 20 dB FM traps in series?) will help here. The latter trick
I had to do with a guy who lives down the street from a 5KW FM at 90.9
to get it to work. 20 db reduction still caused the classic herringbone on analog VHF and "cliffing" on DTV. An additional 10 dB FM attenuator in series got it to a manageable level that barely was visible on analog, and didn't interfere at all with DTV.

As for the sparklies, I have noise suppressors on some of my appliances and that helps with VHF...I would assume it does for UHF. Man, I think today's appliances are awesome but I just wish they'd shield them from outgoing RF better!

As for the parabolics, you usually get reduced multipath because the thing is above your house, although I understand your difficulty in your situation (and that of the lower F-B ratio). Would a 5th generation tuner help you? I assume so.

sregener

12-20-05, 02:21 PM

What would be causing "dots" to be running across my screen with my antenna? I know FM interferance is herringbone shaped. This happens on my lower (4 & 6) stations.

Analog reception, right? It's probably impulse noise. If your house isn't generating it, there isn't much you can do.

Noisykid

12-20-05, 03:22 PM

rgathright

12-20-05, 04:03 PM

Analog reception, right? It's probably impulse noise. If your house isn't generating it, there isn't much you can do.

So a stronger antenna will not help? Yes, it is the analog stations, being all of my HDTV's are in Texas.

sregener

12-20-05, 04:42 PM

So a stronger antenna will not help? Yes, it is the analog stations, being all of my HDTV's are in Texas.

Nope. Might even make it worse.

MAX HD

12-20-05, 05:37 PM

Nope. Might even make it worse.

OK,let's backup a little bit.Poster should have provided more detailed info.He's running a 4228 and experiencing poor reception on CH4 and 6(35-40mi).If he's running a 7777 preamp he needs to add a VHF antenna like a Winegard PR5030 below the 4228,assuming,of course,that it's outside where it should be.

Edit:
I just noticed you already told him in another post that he needed a VHF antenna.Don't know if he added one or not.

dr1394

12-20-05, 05:54 PM

Electrical interference is really hard to track down.....

No it's not. Power company technicians (who have a clue) can easily track it down to the specific pole. I've had this done here in Silicon Valley.

Parabolics are very directional in the direction they are aimed. However, they have very poor front-to-back ratios when compared to other systems, undoubtably due to their porous screens and the fact that their active element is "aimed" backwards. They also accept multipath from a wide range, making them a horrible choice for most digital tuners.
More BS. Instead of just posting your gut feelings about things, how about some factual evidence instead. Even a simulation would be useful.

Ron

sregener

12-20-05, 06:21 PM

1) No it's not. Power company technicians (who have a clue) can easily track it down to the specific pole. I've had this done here in Silicon Valley.

2) More BS. Instead of just posting your gut feelings about things, how about some factual evidence instead. Even a simulation would be useful.

1) Maybe it's easy when there's one source. I heard that a technician came down from the Twin Cities once and found a dozen problems in one block. The fact is, the entire city of Rochester, MN is one RF nightmare for interference. Whole blocks of the shortwave spectrum are drowned out. "Sparklies" interference, multicolored horizontal lines running up the screen, are on all the VHF channels. The local cable company invested thousands of dollars in expensive filters to provide a clean picture on channels 3, 6 and 10, but the cost is picture quality - the resulting pictures are really blurred. Now if you want to come out here and get a problem fixed that the local cable company gave up on, be my guest.

2) Hey, I've never owned a parabolic. I'm basing my understanding of their problems based on GlennL's famous tests done in California in 2001. The 4251 was a dog for local stations, but did very well for weak, distant ones. That's consistent with having multipath problems. You can read his report here: http://www.atechfabrication.com/tests/04-24-01_test_results.htm The relevant quote: "4251 best long distance capability, but not good for multipath."

GlennL did a bunch of other tests, the results of which were discussed here at length at the time, and he became convinced that the 4251 could be bested by a yagi, and his ATF-X300 proved it. He never produced many of them, though.

Tower Guy

12-20-05, 07:00 PM

What would be causing "dots" to be running across my screen with my antenna? I know FM interferance is herringbone shaped. This happens on my lower (4 & 6) stations.

The following is quoted from the Interference handbook that was issued by the FCC many years ago. I am a fan of the alternate method to troubleshoot the problem it is several paragraphs down the page.

a. Electrical Interference

Electrical interference many times will be seen as two or three horizontal lines on the television screen and may be accompanied by a loud buzzing or sizzling sound through the TV speakers or stereo system. Many times the lines move upwards on the television screen and may be on for hours at a time or for a few seconds at a time. In severe cases, the entire screen may be covered with rolling horizontal lines.

A simple way to discover if the source of interference is in your home, is by going to the main fuse or circuit breaker box in your home. Using your TV set or a portable AM radio, determine whether the interference is active. Electrical interference will sound about the same on an AM radio as it does on your TV so you can use a portable AM radio as a detector. Assuming the interference is occurring, you should follow these steps to identify the circuit in your house that has the device causing the interference. Be very careful to avoid contact within anything in the box except the fuses or circuit breakers. Remove one fuse at a time, or shut off one circuit breaker at a time. If the interference stays on, turn the circuit breaker back on and try the next. If you are using your television to know that the interference is active, when you turn off the power to the circuit that supplies power to your TV to test that circuit, plug the TV into another circuit.

If the interference stops when a fuse is removed or a circuit breaker is turned off, go to the area that receives the electricity supplied by the disconnected circuit. Turn the power back on and wait until the interference is present. Next unplug each device on the circuit one at a time. If the interference stops after you unplug a device, you have found the culprit. The device causing the interference must be repaired or replaced. Remember that the device might be hidden. For example, you may have a bad amplifier in your attic, or a defective doorbell transformer that is connected directly to the power circuit.

An alternative method to locating electrical interference is to tune to a quiet frequency at the lower end of the AM dial. If you hear static or a buzzing sound, check to see if it corresponds with the interference to your TV or telephone. If it does, use the portable radio as a detection device to locate the source of the interference.

The noise will be loudest in the room where the interference is originating. Unplug each electrical device in the room one by one until the interference stops.

If you cannot locate the interference source in your own house, check with your neighbors to see if they also receive interference. The house that has the worst interference will most likely be the source of the interference. If your neighbor has strong interference, you may wish to try to track it down with a portable AM radio or run the circuit breaker test described above.

If you determine that the interference is not caused by any device in your home or that of your neighbors, contact the customer service department of your local power company.

rgathright

12-20-05, 07:16 PM

OK,let's backup a little bit.Poster should have provided more detailed info.He's running a 4228 and experiencing poor reception on CH4 and 6(35-40mi).If he's running a 7777 preamp he needs to add a VHF antenna like a Winegard PR5030 below the 4228,assuming,of course,that it's outside where it should be.

Edit:
I just noticed you already told him in another post that he needed a VHF antenna.Don't know if he added one or not.

Right now I have a combination VHF/UHF and the CM 4228. These are both connected to the CM 7777. I thought that getting a bigger VHF antenna it might help the low VHF channels.

sriggins

12-20-05, 07:27 PM

sregener

12-20-05, 07:33 PM

I am a fan of the alternate method to troubleshoot the problem it is several paragraphs down the page.

"An alternative method to locating electrical interference is to tune to a quiet frequency at the lower end of the AM dial. If you hear static or a buzzing sound, check to see if it corresponds with the interference to your TV or telephone. If it does, use the portable radio as a detection device to locate the source of the interference.

The noise will be loudest in the room where the interference is originating. Unplug each electrical device in the room one by one until the interference stops.

If you cannot locate the interference source in your own house, check with your neighbors to see if they also receive interference. The house that has the worst interference will most likely be the source of the interference."

Useful if a lot of people have antennas. There are 3 antennas in a six square block area around my house. And yes, they all have interference as well. Everyone in town has it.

AM interference is pervasive - it's everywhere in town. Walking around with a radio shows that it increases and decreases, but not in a predictable pattern. There are pockets where it's not bad, but those are few and far between.

I've done the circuit breaker test. It isn't in my house.

Still, good stuff for those who might have a single source problem.

Tower Guy

12-20-05, 07:35 PM

Does anyone have opinions on this antenna?

http://www.radioshack.com/product/index.jsp?productId=2103088&cp=&kw=1502160&parentPage=search

I have a BBQ/Bowtie up in the attic now. I get all stations well except 2-1 (43) which is on the same tower as other stations I get. The signal bounces on my DirecTiVo from the high 70s to low 90s. Thanks :)

It works fine if there's no terrain problem and the distance to the transmitters is nominal. I have the slightly larger U-100. (old model #) It's been on my roof for 20 years.

Ennui

12-20-05, 07:35 PM

sriggins:

That looks like a junior version of the antenna I am using:

http://www.winegard.com/offair/pdf/hd9095p.pdf

The Winegard works very well with their AP-8275 preamp for my location picking up LA stations some 70-90 miles away. (With a rotator; it is very sharp.)

Tower Guy

12-20-05, 07:44 PM

Useful if a lot of people have antennas. There are 3 antennas in a six square block area around my house. And yes, they all have interference as well. Everyone in town has it.

AM interference is pervasive - it's everywhere in town. Walking around with a radio shows that it increases and decreases, but not in a predictable pattern. There are pockets where it's not bad, but those are few and far between.

Still, good stuff for those who might have a single source problem.

OK, next step. Use your car radio to drive around town and try the same thing. You will probably find more than one source.

In some cases, power companies have used a flawed method to connect transformers to distribution wires. The ones once used by Niagara-Mohawk were square, with the transformer connected at the bottom and the distribution wire at the top. They clipped on the wire and were not bolted on. Each and every one had to be replaced to cure the problems.

Once I was able to cure line noise temporarily by hitting a bad pole with a sledge hammer. (Don't get caught.) Thankfully, the wires didn't fall on top of me.

The power companies can be fined by the FCC if they fail to fix the problem.

TheRatPatrol

12-20-05, 07:53 PM

Does anyone have opinions on this antenna?

http://www.radioshack.com/product/index.jsp?productId=2103088&cp=&kw=1502160&parentPage=search

I have a BBQ/Bowtie up in the attic now. I get all stations well except 2-1 (43) which is on the same tower as other stations I get. The signal bounces on my DirecTiVo from the high 70s to low 90s. Thanks :)

I have that antenna on my roof right now, it works great for picking up UHF only stations, and its not that obtursive.

TheRatPatrol

12-20-05, 07:55 PM

I have an old antenna on my roof that was here when I bought the house 4 years ago. I have no idea when it was made or who makes it. Looks like it may have a rotor by I have no controller. Never got around to taking it down and am now wondering if it is at all useful for OTA HD. Maybe I could just aim it once, lock it and leave it. Image link below. Thoughts?

Pic: http://noisykid.com/antenna01.jpg

I say plug it in and see what you get. It should get you an HD signal. It looks like its already aimed at the towers. You think it has a rotar, are there stations at different locations in your area?

sriggins

12-20-05, 07:58 PM

I have that antenna on my roof right now, it works great for picking up UHF only stations, and its not that obtursive.

Thanks :)

TheRatPatrol

12-20-05, 08:02 PM

Thanks :)

Do you have a pretty clear view of the towers?

sriggins

12-20-05, 08:20 PM

Do you have a pretty clear view of the towers?

I have no idea. There are some 2 story (3 if you count the attic I guess) townhouses in that direction, beyond that I guess it is pretty clear. I don't have any topo info.

Annoyingly KOIN is fine and it is on the same tower.

TheRatPatrol

12-20-05, 08:22 PM

I have no idea. There are some 2 story (3 if you count the attic I guess) townhouses in that direction, beyond that I guess it is pretty clear. I don't have any topo info.

Annoyingly KOIN is fine and it is on the same tower.

You can try www.antennaweb.org to see what you can get.

sriggins

12-20-05, 08:31 PM

You can try www.antennaweb.org to see what you can get.

I did that and told it i had stuff in the way. It says I need a red, medium directional antenna.

dr1394

12-20-05, 09:25 PM

OK, next step. Use your car radio to drive around town and try the same thing. You will probably find more than one source.

In some cases, power companies have used a flawed method to connect transformers to distribution wires. The ones once used by Niagara-Mohawk were square, with the transformer connected at the bottom and the distribution wire at the top. They clipped on the wire and were not bolted on. Each and every one had to be replaced to cure the problems.

Once I was able to cure line noise temporarily by hitting a bad pole with a sledge hammer. (Don't get caught.) Thankfully, the wires didn't fall on top of me.

The power companies can be fined by the FCC if they fail to fix the problem.
The trick that the PG&E technician showed me was to use a radio that could tune through the VHF and UHF spectrum. As he tracked the source, he would tune the radio to progressively higher frequencies to pinpoint the offending power pole.

In Silicon Valley, the typical problem is arcing on the insulators due to pollution deposits. The fix is to actually clean the insulators.

BTW, if the noise goes away during rain, this is a sure sign of power line arcing. The rain temporarily disrupts the arc path. Noise can also come and go during the day as the dew point changes.

PG&E was very willing to fix these problems. Power line arcing expends electricity that does not get billed to anyone. It's in their best interest to repair arcing since it directly affects their bottom line.

When I had my problems repaired, there was a special guy that handled all the complaints. He had helped so many amateur radio operators, that the big Northern California DX club threw him a huge party when he retired, even though he wasn't a ham himself.

Ron

sregener

12-20-05, 09:30 PM

OK, next step. Use your car radio to drive around town and try the same thing. You will probably find more than one source.

I've done it. It's everywhere.

I'll post a pic of the transformer (I'm lucky I have one in my backyard) tomorrow. I'd do it now, but that pesky ball of gas 93 million miles away is having trouble penetrating the earth.

rwantennasat

12-20-05, 09:57 PM

I have an old antenna on my roof that was here when I bought the house 4 years ago. I have no idea when it was made or who makes it. Looks like it may have a rotor by I have no controller. Never got around to taking it down and am now wondering if it is at all useful for OTA HD. Maybe I could just aim it once, lock it and leave it. Image link below. Thoughts?

Pic: http://noisykid.com/antenna01.jpg
Looks like an older TDP antenna. they work pretty well depending on your distance from stations. You should replace the coax and put a good new transformer at the antenna and it should work out. if all stations in same direction then dont worry about rotor

MAX HD

12-20-05, 11:20 PM

The trick that the PG&E technician showed me was to use a radio that could tune through the VHF and UHF spectrum. As he tracked the source, he would tune the radio to progressively higher frequencies to pinpoint the offending power pole.

In Silicon Valley, the typical problem is arcing on the insulators due to pollution deposits. The fix is to actually clean the insulators.

BTW, if the noise goes away during rain, this is a sure sign of power line arcing. The rain temporarily disrupts the arc path. Noise can also come and go during the day as the dew point changes.

PG&E was very willing to fix these problems. Power line arcing expends electricity that does not get billed to anyone. It's in their best interest to repair arcing since it directly affects their bottom line.

When I had my problems repaired, there was a special guy that handled all the complaints. He had helped so many amateur radio operators, that the big Northern California DX club threw him a huge party when he retired, even though he wasn't a ham himself.

Ron

When I had TVI problems last year the power company sent a dedicated tech(70mi) to look for problems.The interference was so sporadic(15-30sec bursts several times a day-some days nothing) he couldn't find anything initially.He made three trips before we found the problem.It was an old house about 200ft away with old post and tube wiring in the attic that was intermittently arcing(coronal arc).

The interference would tear up all the tv channels with VHF being the worst.Two large static bands on the screen with audible noise.The equipment he used was a 3 element yagi and a receiver tuned to around 220-230 Mhz.When I walked around the neighborhood with a portable radio I could pick up the noise better on FM than AM but never could pinpoint the source.He happened to be standing in front of the guys house when the arc kicked in,so he went over to the meter base and that thing he had went nuts.

Needless to say,I was impressed.The tech said that most problems he finds come from within someone's home.

billinabnett

12-20-05, 11:40 PM

OK,now I understand.Will be interesting to see how this works.I'd still like to know what your intended target is for this array.You mentioned you're in East Texas.Thanks.

Have Not.... Want Not... Seriously... being in experimental mode, we will just have to see the performance marks as they fall... I wish it would warm up so i can get it up on the tower....

sregener

12-21-05, 07:36 AM

Right now I have a combination VHF/UHF and the CM 4228. These are both connected to the CM 7777. I thought that getting a bigger VHF antenna it might help the low VHF channels.

Are you sure you need a preamplifier for VHF? And if you do, do you need as much as the 7777 gives? Removing the preamp might make that static go away (or at least greatly reduce it.) Note: you must remove the outdoor unit. Unplugging the indoor unit will not work for testing; the outdoor unit needs power to pass a signal.

If removing the preamp improves things but you still need the amplification on UHF, I'd try a Winegard AP-4700 or -4800. You'd also need a Channel Master #0549 to combine the UHF and combo antennas as the Winegards don't have separate inputs.

sregener

12-21-05, 07:46 AM

Time for the heavy artillery. Quad-shielded RG-6 and a 50dB FM trap (or maybe two 20 dB FM traps in series?) will help here. The latter trick
I had to do with a guy who lives down the street from a 5KW FM at 90.9
to get it to work. 20 db reduction still caused the classic herringbone on analog VHF and "cliffing" on DTV. An additional 10 dB FM attenuator in series got it to a manageable level that barely was visible on analog, and didn't interfere at all with DTV.

As for the sparklies, I have noise suppressors on some of my appliances and that helps with VHF...I would assume it does for UHF. Man, I think today's appliances are awesome but I just wish they'd shield them from outgoing RF better!

I've already done better than quad-RG6. I've got quad-RG11. I'm debating getting a VHF-hi/VHF-lo combiner and leaving the VHF-lo side "dancing in the wind."

But that won't resolve the sparklies, which I suspect are a much more difficult problem for distant reception. The FM interference, at least, is constant - it doesn't change. But the moving sparklies will confuse the heck out of a tuner that is already suffering from a weak signal. As I've stated elsewhere, the RF interference is not coming from my house.

sregener

12-21-05, 07:49 AM

As for the parabolics, you usually get reduced multipath because the thing is above your house, although I understand your difficulty in your situation (and that of the lower F-B ratio). Would a 5th generation tuner help you? I assume so.

I can't put a parabolic on my tower - it couldn't handle the windload (6 ft-lbs max). I'm 54' AGL right now.

I'm actually intrigued by the Samsung Gemini chipset, as it appears to be a major step up at receiving weak signals. But you know the story; it's been tested but there are no production devices with it...

cpcat

12-21-05, 08:20 AM

I'm debating getting a VHF-hi/VHF-lo combiner and leaving the VHF-lo side "dancing in the wind."

.

That's the best way to get rid of FM that I've been able to find. The disadvantage obviously is you lose low band but most don't need it. It's too prone to interference and the antennas required are too damn huge anyway. It does "get out" though.

sregener

12-21-05, 08:33 AM

In some cases, power companies have used a flawed method to connect transformers to distribution wires. The ones once used by Niagara-Mohawk were square, with the transformer connected at the bottom and the distribution wire at the top. They clipped on the wire and were not bolted on. Each and every one had to be replaced to cure the problems.

Here she is...

(I apologize for the sideways picture, but apparently the web site isn't bright enough to know that a 480x720 picture is *SMALLER* than an 800x600, the maximum size permitted.)

Let me know if you need a closeup of any part, as I can crop the 6MP image for details.

bernieoc

12-21-05, 09:10 AM

I have a single ch Taco 5y3s (ch 3) and a Wineguard PR 8800 (8bay UHF) on the way. I also have a CM 7777 to combine them.
If the CM 7777 is not needed or creates harm:
A- VHF needs it
B- UHF needs it
C- neither needs it
How would I combine them? A two way splitter in reverse or a CM 0549 combiner.
I picked the PR8800 because it looks good for low UHF (I receive ch 18 thru 36) and hope it will cover a 30 deg spread (47 miles and 23 miles). The ch 3 antenna is for a flakey PBS at 47 miles.
At the risk of putting too much into one post - One more question.
A while back a comment explained why Pr 8800 and DB 8 were not as good on high VHF as the CM 4228 (I have one UHF that may revert to CH 10 or 13). Something about a non continuous screen?
Is there a modification I could make to change that without needing a metal fabrication shop?
By the way, this forum has made 'me' an antenna information source for my children, grandchildren and friends. Isn't that a laugh!

sregener

12-21-05, 09:17 AM

I have a single ch Taco 5y3s (ch 3) and a Wineguard PR 8800 (8bay UHF) on the way. I also have a CM 7777 to combine them.
If the CM 7777 is not needed or creates harm:
A- VHF needs it
B- UHF needs it
C- neither needs it
How would I combine them?

A while back a comment explained why Pr 8800 and DB 8 were not as good on high VHF as the CM 4228 (I have one UHF that may revert to CH 10 or 13). Something about a non continuous screen?

If C, a simple splitter will suffice. You only need a simple splitter/combiner, used in reverse. The VHF Ch3 antenna won't pick up enough UHF to matter, and vice versa.

If A & B, just plug each into the appropriate connector on the 7777 (it has one for VHF and one for UHF.)

If you need just UHF or VHF amplification, it's going to be tricky with the 7777. You need to do the combination *after* the indoor unit, which means running two lengths of coax from your antennas to wherever the indoor unit is. Then, you can combine the amplified UHF or VHF with the unamplified VHF or UHF with a simple splitter/combiner.

I wouldn't worry about the hi-VHF at this point. If it becomes a problem later, you could add a hi-VHF antenna to the mix.

holl_ands

12-21-05, 12:32 PM

If you look at the recently updated NEC Simulation results at the bottom of the fol webpage,
you'll see that the PR8800 has about as much gain as a pair of rabbit ears across the upper VHF band:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

So if the future VHF stations aren't too far away, the PR8800 may be adequate.

Someone would need to do some additional NEC simulations for the PR8800 and DB-8 to investigate whether
various modifications improve performance in VHF bands....and at what detriment to UHF performance.

Since the PR8800 utilizes resonating rear reflector elements, like a classic Yagi-Uda antenna,
I would expect to see the UHF performance severly affected if you simply interconnect the PR8800's
individual reflector elements into a single long reflector rod.

Sound like a simple exercise for the NEC student.....

==================================================
FYI: Click on the CM-4228 to see the mixed results for interconnected and
non-interconnected rear screen results. This comparison was very recently added.

However, these are computer SIMULATIONS and hence are subject to the GIGO effect.
For example, if you look at the source files (see top of webpage for link), you'll see that
the (older Mar05) CM4228 file doesn't include the horizontal support bars that interconnect
the two 4-Bay sections and also acts as an (intermittent) short across the two back screens (see attached photo).

I suspect that the Mar05 file is for the original results and does not reflect the recent revisions
for CM4228 results with and without interconnected screens.

cpcat

12-21-05, 01:48 PM

If you look at the recently updated NEC Simulation results at the bottom of the fol webpage,
you'll see that the PR8800 has about as much gain as a pair of rabbit ears across the upper VHF band:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

. Rabbit ears properly extended horizontally to match approx 1/2 wave tip to tip for the desired vhf channel will provide around 2dbi gain (or 0dbd by definition). The simulation shows between -8 and -1 dbi gain for the PR8800 in the high vhf band.

The "rabbit ears" graph depiction on the simulation assumes they are positioned at a 45 degree angle and extended to 40 inches, i.e. not utilized to their fullest for the desired channel.

http://www.kyes.com/antenna/rabbitear.html

newsposter

12-21-05, 03:27 PM

Philadelphia is in the top-10 markets, and all major networks (including NBC, but not WB) were required to be full powered a few years back; the 7/1/05 deadline was a last-ditch, last minute deal. Those stations are probably already maximized (check your local thread for confirmation) due to interference protection in the crowded NE. I wouldn't look for any dramatic improvements from the big 4 until the analog shutdown.

The FCC shows WPHL-DT as being full-powered (i.e. licensed) at 500kw, although depending on your direction it could be half of that because they have chosen not to blast a strong signal to the W and NE. Still, with a good setup and some luck, you shouldn't have any trouble getting a 250kw station at 50 miles.

here's a list of my stations. I can't get 54 and 42 in reliably but have acceptable readings on the rest. So once there's a shutdown, will those power readings go up to 1000? And if you are saying 500 is the max now, I guess I"m screwed on 54 as they have nowhere to go. Amazing that I get channel 32 with only 250 watts because of the height I'm assuming.

uhf station signal power height
26 (cbs3) 90-92 770/375
31 (pax61) 90-91
32 (upn 57) 85-90 250/400
34 (wbye35) 80-85 358/377
42 (fox 29) 25-45 305/161
54 (wb 17) 40-60 500/354
64 (abc 6) 71+ 500/390
67 (nbc10) 71+ 560/377

sregener

12-21-05, 04:27 PM

I can't get 54 and 42 in reliably but have acceptable readings on the rest. So once there's a shutdown, will those power readings go up to 1000? And if you are saying 500 is the max now, I guess I"m screwed on 54 as they have nowhere to go. Amazing that I get channel 32 with only 250 watts because of the height I'm assuming.

uhf station signal power height
26 (cbs3) 90-92 770/375
31 (pax61) 90-91
32 (upn 57) 85-90 250/400
34 (wbye35) 80-85 358/377
42 (fox 29) 25-45 305/161
54 (wb 17) 40-60 500/354
64 (abc 6) 71+ 500/390
67 (nbc10) 71+ 560/377

WPHL-DT-54 will revert to channel 17. How much power they will apply remains to be seen. Their current allocation at 54, however, is at maximum power and will not increase.

While 1000kw is the maximum allowed ERP for a digital UHF station, no station is required to put out that much signal. I would guess that most of those stations are limited by neighboring markets, and they might get a little more "leg room" once the analogs go away.

As you correctly guessed, Fox's minimal antenna height is the real problem. Broadcasting power takes second place to antenna height for reception. They have an application to increase power to 1000kw, and they have a construction permit to go up to 280m. Things may improve with them before the analog shutdown.

Your local OTA thread is probably a better place to get specific information about the specific channels in your market.

I don't think you've listed your receiving equipment (antenna, preamp, tuner model) but you may be able to improve your results by upgrading any of them that are inferior. I noticed remarkable improvements moving my antenna from my roof to a 54' tower, but not everyone has as understanding a wife as I do. :o

MAX HD

12-21-05, 05:58 PM

I can't put a parabolic on my tower - it couldn't handle the windload (6 ft-lbs max). I'm 54' AGL right now.

That tower of yours can handle almost 4X more than you have up there right now,though I wouldn't recommend a 7ft parabolic.The BX-48 is apparently what you have,with about 6ft of masting above the apex,which puts your XG91 at 54ft.That tower is rated at 6sq.ft./120lb lateral wind force @70mph,with the antenna mass centered 3ft above the apex.The XG91 is only 1.5 sq.ft. and has about 35lbs of wind force at its max rating of 80mph.That's why you don't see it moving around much when the wind is blowing.

You could easily add a Band A antenna(less than 2sq.ft.) below the XG91 and improve all those problematic channels below 38.

I found a pic of your tower.Looks like it has a rotor shelf.If you ever redo things,I would explore the possibilty of using that shelf for the rotor,and use a thrust bearing at the apex.

Just some thoughts.

Tower pic:
http://archive.avsforum.com/avs-vb/attachment.php?postid=4154043&fullpage=1

Rohn BX tower spec:
http://www.antennasystems.com/bxload.html

rgathright

12-21-05, 07:13 PM

Are you sure you need a preamplifier for VHF? And if you do, do you need as much as the 7777 gives? Removing the preamp might make that static go away (or at least greatly reduce it.) Note: you must remove the outdoor unit. Unplugging the indoor unit will not work for testing; the outdoor unit needs power to pass a signal.

If removing the preamp improves things but you still need the amplification on UHF, I'd try a Winegard AP-4700 or -4800. You'd also need a Channel Master #0549 to combine the UHF and combo antennas as the Winegards don't have separate inputs.

I have a spare Rat Shack amp so may try it in place of the CM 7777 on just the CM 4228. Would a separate VHF work better than a combo VHF/UHF being I have the CM 4228 for the UHF?

sregener

12-21-05, 07:50 PM

That tower of yours can handle almost 4X more than you have up there right now,though I wouldn't recommend a 7ft parabolic.

You could easily add a Band A antenna(less than 2sq.ft.) below the XG91 and improve all those problematic channels below 38.

I found a pic of your tower.Looks like it has a rotor shelf.If you ever redo things,I would explore the possibilty of using that shelf for the rotor,and use a thrust bearing at the apex.

I had a Winegard HD8200P up there before the 91XG. That thing really swayed. The 91XG still moves around a good bit, but wind here can be downright nasty. I haven't watched it while the tornado sirens have been going off, though - I prefer to watch the radar from the storm shelter.

I don't have many problematic channels below 38. In fact, the 91XG does a really good job on most of those channels. My biggest problem channel is 50, but that probably has more to do with their transmitting antenna issues than my receiving setup. WHLA-DT, for instance, isn't supposed to get close to Rochester (http://www.fcc.gov/fcc-bin/FMTV-service-area?x=DS658573.html) on channel 30, but the days I don't get a solid lock are few and far between. WCCO-DT (32) from the Twin Cities also isn't supposed to get close to Rochester, but they are my most reliable station from the Cities (http://www.fcc.gov/fcc-bin/FMTV-service-area?x=DT584286.html).

I'll probably replace the antenna once they come out with yagi/corner-reflectors that are optimized for channel 51 instead of 67.

I didn't do the install - I hire professionals to do the tower work. The thrust bearing is a good idea, though.

holl_ands

12-21-05, 08:00 PM

Rabbit ears properly extended horizontally to match approx 1/2 wave tip to tip for the desired vhf channel will provide around 2dbi gain (or 0dbd by definition). The simulation shows between -8 and -1 dbi gain for the PR8800 in the high vhf band.

The "rabbit ears" graph depiction on the simulation assumes they are positioned at a 45 degree angle and extended to 40 inches, i.e. not utilized to their fullest for the desired channel.

http://www.kyes.com/antenna/rabbitear.html
"Getting the Most out of Rabbit Ears" link addresses different orientation and lengths:
http://www.hdtvprimer.com/ANTENNAS/RabbitEars.html#Getting
You lose about 2 dB by using the typical 40-45 degree vice co-linear position.

However, these are all "classic" free-space gain, presuming nothing is near the rabbit ear antenna.
You will probably lose even more if you lay the elements flat against your TV.
The nearby metal inside is going to effectively suck the signal out of the antenna.

And that is why most people have found, through many years of trial and error,
that the best orientation is like a pair of, well, Rabbit Ears....at about 40-45 degrees.
And unless you only have one VHF station to deal with, most people will extend it to one setting
and never try anything else (usually thinking more is better???).

The 45 degree angle also helps to pick up both the horizontal and vertical polarization (if any),
thereby providing a small amount of polarization diversity gain.

=================================================
FYI: Here are some links to ACTUAL ANTENNA MEASUREMENTS:
http://hdtv.forsandiego.com/messages/1/3476.html#POST18805

sebenste

12-22-05, 12:10 AM

I've already done better than quad-RG6. I've got quad-RG11. I'm debating getting a VHF-hi/VHF-lo combiner and leaving the VHF-lo side "dancing in the wind."

But that won't resolve the sparklies, which I suspect are a much more difficult problem for distant reception. The FM interference, at least, is constant - it doesn't change. But the moving sparklies will confuse the heck out of a tuner that is already suffering from a weak signal. As I've stated elsewhere, the RF interference is not coming from my house.

Sregener,

As for the quad-shielded RG-11, 3 words: you're my hero! :D Most excellent.
The FM interference, though constant, is a pain. Have you tried putting two traps in series to see if it helps you?

As for the sparklies, it almost sounds like one of those 100 kilovolt main trunk
lines goin g into town is royally messed up somewhere, which causes those over quite a wide area. THAT should be easy to find. Call up your power company and tell 'em to fix it!

DR_LaRRY_PEpPeR

12-22-05, 07:09 AM

You guys aren't going to believe this, but for my reception the 91XG IS NOT performing better than my R-S combo! :eek:

Even when testing, I assumed it was a bit better just holding it in position, with a cable (60' I think) going directly to tuner, but not much better... Now in more even comparisons, it has yet to noticably outperform the R-S.

After I put the 91XG on a 5' eave-mounted mast, I didn't use the CM-7777 pre-amp yet, just to get an idea without. The first night, I did get to actually watch KDNL (channel chart below) basically for the first time during primetime. So that was better than the R-S, but the 91XG was also higher than the R-S had ever been. The next day I connected the old R-S 25db/6db noise amp in the basement after the ~60' cable (only about 12' after to the tuner). That improved things pretty well! The next day I swapped it for the 7777 in the basement also, to see how the 2db noise figure would improve things: about a notch or two on the DirecTV receiver signal meter, maybe "10%".

Before putting the 7777 on the mast, I wanted to compare the 91XG and R-S antennas under more of the same conditions than I had before. First both with no amp, then with, etc. I was shocked when without the amp, the R-S was as good or better, except on channel 26. With the amp, they're pretty much the same that I can't really say a difference, though I think the R-S might do barely better on a couple channels (hitting the high side of the ranges below more often), except maybe on 26 still.

-- Signal Level --
Channel Direction Miles ERP (kW) 91XG R-S | w/CM-7777
KTVI 2 (43) 105.5 43.1 1000 63-69 69 | 86-93
KMOV 4 (56) 104.6 47.1 1000 0-30 0-36 | 69-77
KSDK 5 (35) 101.9 44.7 838 63 69 | 79-93
KETC 9 (39) 110.7 43.0 125 0-20 0-20 | 45-63
KPLR 11 (26) 101.4 45.0 1000 45-54 0-45 | 69-77
KDNL 30 (31) 100.8 44.7 1000 63-69 69 | 77-79
WRBU 46 (47) 121.5 41.6 109 45-63 45-63 | 63-69

Those readings were taken within an hour in the evening. The antennas have been pointed at about 105 degrees. The 91XG is aimed upward at about 3 degrees, which is probably a bit above the horizon approx. 3000' feet away.

Another thing I was really surprised about was that the signals were no higher with the 7777 on the mast than after 60' of RG-6?! I thought I might gain 6db, with 2db cable-loss, 2db VSWR (??), and moving the amp's 2db noise up the line... :confused:

The signal needs to be at 45-54 (fluctuating, not steady 45) to lock, and so this is the first time I've received KETC on 39 (during "regular hours") since early mornings with the R-S in the attic. Although it's been freezing/breaking up pretty often as I type this (with the 91XG up there now)...

Analog KDNL 30 looks the best it ever has -- the snow is pretty much all gone! Just a little noise/grain.

It looks like I'm just going to stick with the R-S (was gonna just be for analog VHFs) since it's providing fine reception now. Man, that 7777 is what really makes the difference! :cool: But I don't know what to do with the 91XG. :( It sounds like Solid Signal won't take back "items that you have installed or disassembled." (www.solidsignal.com/returns_warr.asp) Maybe a neighbor would buy it since he doesn't have an antenna yet for his new plasma.

cpcat

12-22-05, 07:21 AM

"Getting the Most out of Rabbit Ears" link addresses different orientation and lengths:

The 45 degree angle also helps to pick up both the horizontal and vertical polarization (if any),
thereby providing a small amount of polarization diversity gain.

If you look at the recently updated NEC Simulation results at the bottom of the fol webpage,
you'll see that the PR8800 has about as much gain as a pair of rabbit ears across the upper VHF band:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

0dbd gain by convention is referenced to a simple dipole and is equivalent to around 2dbi. Rabbit ears extended to the channel-specific length for vhf and positioned horizontally are equivalent to a simple dipole. The PR8800 has from -1 to -8 dbi gain across the high vhf band according to the computer simulation you referenced.

There are no vertically polarized TV transmitters in the US.

newsposter

12-22-05, 07:45 AM

I don't think you've listed your receiving equipment (antenna, preamp, tuner model) but you may be able to improve your results by upgrading any of them that are inferior.

Except for what is in my sig I only have a levitron 25db amp from home depot. I have it placed : DB8----75ft rg6----amp----50ft rg6---hr10-250

I do have the ability to put it right at the DB8 since i have an attic mount. Think that would make a difference? Or just keep it at the 75ft mark?

sregener

12-22-05, 07:45 AM

You guys aren't going to believe this, but for my reception the 91XG IS NOT performing better than my R-S combo! :eek:

The first night, I did get to actually watch KDNL (channel chart below) basically for the first time during primetime.

Hmmm. Well.

The most important thing with any antenna system is location, location, location.

I would strongly urge you not to judge the 91XG too quickly. I ripped mine down before I realized just how much better the 91XG was. Still, there were times where reception on my rooftop with a Winegard 7084P was as good or better than the 91XG on a 54' tower. The atmosphere plays tricks on us, and the upper midwest was crackling last night, meaning a bowtie might have gotten you good results.

Test the 91XG during the daytime hours before you judge it as worthless.

The difference between a good antenna and a great one is usually subtle with digital reception. The fact that you locked on a station you never had before indicates to me that maybe the 91XG is better.

I would not tilt the 91XG, or any antenna for that matter, unless you have verified that gives you the best results. It is highly directional and a 3-degree difference will dramatically reduce its gain. Are you sure you aimed it precisely - not just eyeballed? I find for marginal stations, a 2-degree difference is all it takes to go from rock-solid to breakups. Yes, it's that sensitive. The Radio Shack probably is not that sensitive, as it has lower gain it will have a wider acceptance angle.

sebenste

12-22-05, 11:35 AM

Sregener,

As for the sparklies, it almost sounds like one of those 100 kilovolt main trunk
lines goin g into town is royally messed up somewhere, which causes those over quite a wide area. THAT should be easy to find. Call up your power company and tell 'em to fix it!

Sregener,

OK, I now saw the paragraph where you did call the power company. It almost sounds like the entire distribution system is old and leaking like a sieve. In northeastern Illinois, line noise was amazing, and still is in a number of areas, but our local power company is replacing every line. 3 or 4 years ago, the power would go out if you sneezed on a line, and the power company got fined huge. They had more reliable power in Baghdad and Beirut than in some areas around Chicago for a while. I wonder if that's the case with you? If it is, then I sympathize wholeheartedly, and I'd get the regulatory commission for your state to hound those guys to replace the lines (besides, if that is true, it's costing them huge bucks anyway!).

sregener

12-22-05, 04:08 PM

I wonder if that's the case with you? If it is, then I sympathize wholeheartedly, and I'd get the regulatory commission for your state to hound those guys to replace the lines (besides, if that is true, it's costing them huge bucks anyway!).

The power grid here has been fairly reliable.

If I really wanted those distant stations, I'd probably hound them, but I'll just do without. Sure, it'd be nice to get a CBS and NBC from Wisconsin, and a Fox and NBC from the Twin Cities, but I'll get all those networks from within my market just fine. Solving the impulse noise problem wouldn't resolve the FM problem, though, so I'd still be out of luck. And then there's the fact that I have a UHF-only antenna, so VHF "performance" isn't what it's cracked up to be.

This all started because somebody was excited about the analog shutdown, and my saying I'll lose more than I'll gain. I still think so. I'm just not willing to spend the time, energy, and money to fix the problems I have with hi-VHF. After all, that's why I went digital in the first place.

bobchase

12-22-05, 04:30 PM

0dbd gain by convention is referenced to a simple dipole and is equivalent to around 2dbi. Rabbit ears extended to the channel-specific length for vhf and positioned horizontally are equivalent to a simple dipole. The PR8800 has from -1 to -8 dbi gain across the high vhf band according to the computer simulation you referenced.

There are no vertically polarized TV transmitters in the US.
cpcat
Many US TV stations have a vertical component. VHF stations are often employ circular polarization with full power on both poles. UHF stations, when they employ a vertical component, tend to be elipticle with 15% or 25% power in the vertical radiators being common choices. However, there are far fewer UHF stations that use it because of the electric bill penalty.

Bob Chase

Neil L

12-22-05, 10:31 PM

cpcat
Many US TV stations have a vertical component... However, there are far fewer UHF stations that use it because of the electric bill penalty.I'm curious, what advantage does a vertical component offer? I'm thinking that is why a X works good as a VHF antenna, and rabbit ears work good (often better) at 45 degrees than at 90 degree as a true dipole. But still don't understand why a broadcaster would choose one way or the other on the vertical component.

cpcat

12-22-05, 11:10 PM

cpcat
Many US TV stations have a vertical component. VHF stations are often employ circular polarization with full power on both poles. UHF stations, when they employ a vertical component, tend to be elipticle with 15% or 25% power in the vertical radiators being common choices. However, there are far fewer UHF stations that use it because of the electric bill penalty.

Bob Chase

I didn't say that none had a vertical component. I said that none were vertically polarized. I have at least one station (WJHL Bristol) which is elliptical. You can turn your antenna on its side if you want, I'll keep mine horizontal. :p

tivo1

12-22-05, 11:33 PM

for instnace.. im say 30-40 miles from most stations.. most are within 102 and 103 degrees, but there are a few at 108..

So i was wondering if i can get all these? or is it even worth climbing back up on the roof to try?

any input would be appreciated

tivo1

12-23-05, 10:07 AM

anyone? would kind of like to get things done today, if its a possibility.

pyedog

12-23-05, 11:00 AM

anyone? would kind of like to get things done today, if its a possibility.

It depends on what antenna you use. If you mean that you have all of your stations within 6 degrees of the same direction, you should be fine. If you mean you have stations over 100 degrees apart it is a much tougher problem.

In addition, it depends on what is between you and the towers - I'd start by using www.antennaweb.com and see what they predict.

firemantom26

12-23-05, 09:50 PM

I just had a antenna guy stack two CM- 4228 vertically with equal length of coax going into a two way splitter than into my Channel Master 777 amp. The problem is it is worse now on reception than it was before. I am so frustrated on the work that he done, What could be wrong . Any help on this matter would be greatly appreciated .

TotallyPreWired

12-23-05, 10:00 PM

firemantom26

12-23-05, 10:12 PM

Well, it could be a 'phase' problem or maybe the combiner. Did you read this? (http://www.hdtvprimer.com/ANTENNAS/16bay.html)
....jc
Yes I have read this and I not sure what this means,also how much spacing between both antennas.

TotallyPreWired

12-23-05, 10:36 PM

Yes I have read this and I not sure what this means,also how much spacing between both antennas.
The pics show the screens touching. Also, check the polarity:
There is a chance that you will mix up the polarities such that the two antennas subtract instead of add. Doing this will result in two forward lobes, reduced in size, with a null straight out the front. After the antenna is fully hooked up, you should rotate the antenna to check for this pattern. If so then you have to reverse the connections on one of the antennas. The antennas come with a balun that has a “China” stamp on one side. I believe this stamp is the key to getting addition on the first try.
....jc

AntAltMike

12-23-05, 10:55 PM

firemantom26

12-23-05, 11:02 PM

It is surely easier for firemantom26 to swap the two leads on one of his baluns than to physically rotate one entire antenna. Also, he should make sure that he is using two physically identical baluns.

The vertical spacing between those two 8-bay bowtie antennas is relatively unimportant. Some people try to make sure that the spacing between the top bowties on the bottom antenna and the bottom bowties on the top antenna is the same as the vertical spacing of the bowtie elements within each antenna, and I think that might require that the screens overlap a little.

folks what is this baluns that you are talking about, also the CM-7777 comes after the splitter right?

sebenste

12-23-05, 11:58 PM

The power grid here has been fairly reliable.

If I really wanted those distant stations, I'd probably hound them, but I'll just do without. Sure, it'd be nice to get a CBS and NBC from Wisconsin, and a Fox and NBC from the Twin Cities, but I'll get all those networks from within my market just fine. Solving the impulse noise problem wouldn't resolve the FM problem, though, so I'd still be out of luck. And then there's the fact that I have a UHF-only antenna, so VHF "performance" isn't what it's cracked up to be.

This all started because somebody was excited about the analog shutdown, and my saying I'll lose more than I'll gain. I still think so. I'm just not willing to spend the time, energy, and money to fix the problems I have with hi-VHF. After all, that's why I went digital in the first place.
Sregener,

Power grid reliability may be fine, even if it's spewing a boatload of rf garbage into the air...and I suspect that's what is happening to you. Remember, as analog cell phones and other analog devices get turned off in 2009 (it won't be just DTV!), you may get a little less interference, especially as the stations go to even higher power. Don't rule out reliability just yet...there are too many variables
between now and February, 2009 (if that date holds).

firemantom26

12-24-05, 12:28 AM

folks what is this baluns that you are talking about, also the CM-7777 comes after the splitter right?

Did a google search on baluns.

You will have two wingnuts in the center of each antenna. Those should be hooked to two wires which then go into a small cylindrical structure (the balun). The coax then comes out of the balun. Reverse the wires to the wingnuts on one of the antennas and see if that makes the signal better.

Happy holidays to all and thank you for all your help.

Tatmtt2120

12-24-05, 12:45 AM

I am a noob with HD local channels and antennas. I currently have directv but I want my locals in HD so I am in need of an OTA antenna. I live on Beale AFB and antennaweb.org says I'm roughly 60 miles from the towers in Sacramenta, CA. For me to receive local channels in HD can I use an amplified indoor antenna or do I need to buy a more expensive outdoor antenna? I would like to stay under $50 if at all possible.

This was recommended to me by the circuitcity salesman:
http://www.circuitcity.com/ssm/Terk-Antenna-TV5-/sem/rpsm/oid/54455/catOid/-12886/rpem/ccd/productDetail.do
or this one

http://www.circuitcity.com/ssm/Terk-Indoor-HDTV-Antenna-HDTVi-/sem/rpsm/oid/91092/catOid/-12886/rpem/ccd/productDetail.do

DR_LaRRY_PEpPeR

12-24-05, 06:07 AM

Hmmm. Well.

The most important thing with any antenna system is location, location, location.

I would strongly urge you not to judge the 91XG too quickly. I ripped mine down before I realized just how much better the 91XG was. Still, there were times where reception on my rooftop with a Winegard 7084P was as good or better than the 91XG on a 54' tower. The atmosphere plays tricks on us, and the upper midwest was crackling last night, meaning a bowtie might have gotten you good results.

Test the 91XG during the daytime hours before you judge it as worthless.

The difference between a good antenna and a great one is usually subtle with digital reception. The fact that you locked on a station you never had before indicates to me that maybe the 91XG is better.

I would not tilt the 91XG, or any antenna for that matter, unless you have verified that gives you the best results. It is highly directional and a 3-degree difference will dramatically reduce its gain. Are you sure you aimed it precisely - not just eyeballed? I find for marginal stations, a 2-degree difference is all it takes to go from rock-solid to breakups. Yes, it's that sensitive. The Radio Shack probably is not that sensitive, as it has lower gain it will have a wider acceptance angle.

I have had both antennas up during all hours of the day now. :) It doesn't change much at all between day and night or anything like it did before the leaves fell off and it was warmer, etc.

I didn't call the 91XG worthless. ;) That's why I emphasized "for my reception." Using the 7777, I'm getting the station I never had before with either antenna. But it's just a bit higher reading with the Radio Shack -- caused somewhat by being more off-axis than the other channels, and the R-S is less directional...

As far as the angles, going by the plots on HDTV Primer (www.hdtvprimer.com/ANTENNAS/XG91.html), 3-degrees tilt isn't going to make a difference. :) I was just trying to slightly aim at the horizon. Yesterday before replacing the 91XG with the R-S again, I tried rotating it left and right by about 5-degrees. Only a minor change in signal levels (<10%) in that ~10-deg. window, which is what I'd have guessed after my previous results and seeing its plots (but I believe your 2-degree differences, being as far as you are :))

After putting the R-S back up, I was more convinced than ever that it's working better for me. :D Signal level on half the channels went up about a notch -- the ones where I like to see that happen! :) So I don't know -- maybe the 91XG is just too directional for me. :confused: One thing I forgot to do before taking it down was taking the front 1/3rd section of the boom off, making it less directional, and more like a 43XG, right? (Although I think the reflector screens are a bit bigger.) Would like to see how that changes things, so hopefully I'll try that later today before I start disassembling it for return. Obviously I don't need it when the R-S with the nice 7777 amp is getting good results. :) BTW, it looks like Solid Signal will take antennas back, since they have open-box ones for sale, and I'm sure a lot of them had been assembled...

DR_LaRRY_PEpPeR

12-24-05, 06:23 AM

etcarroll

12-24-05, 09:18 AM

I still have the old balun with cracked insulation and all on the Radio Shack antenna. I'm trying to figure out what better-than-Radio-Shack one to replace it with after seeing holl_ands' balun loss measurements (http://hdtv.forsandiego.com/messages/1/2489.html). Of the ones tested, Lowes has the Philips on their site. Home Depot doesn't have the RCA on theirs (could be in-store?). And I can't find a CM "3075" -- the 0089 and 0090 are the models on their site -- same quality? Found one of them at Wholesale Electronics (www.weisd.com/store2/CM%207990.html), but the shipping is like 3x more than the balun. So anything better than the Philips that could be purchased locally, or online with less shipping, etc.?

Well, I should recover a little more dB from the antenna with a better balun. :cool:

Balun ID question?

I looked at the Excel from above, I've had the Phillips balun on a CM4228 for a year. My PBS station has always been iffy, I hope getting a db or two more of signal to my tuner will help.

I bought the antenna from another AVS member, who said it had little use, I don't doubt it.

I swapped out the balun that came with it, no ID, just says MAde in China, for the Phillips, thinking newer would be better. Now I wonder if I have a better balun sitting here in my parts bin, so my question is "How can I id this balun as a CM balun?"

Again, it is stamped, Made in China, nothing else.

Physically, the barrel or body has 2 grooves, the out put nipple is 'flattened' on one side, and the 2 input wires seem to be a bit heavier gauge than the Phillips unit has.

sregener

12-24-05, 09:43 AM

(but I believe your 2-degree differences, being as far as you are :))

Actually, I have a station about 40 miles away that is just as sensitive. Of course it's 6kw and the transmitting antenna is 0m AGL.

TVSaurus

12-24-05, 12:21 PM

I installed a 4221 last week and could only receive 2 of the 3 locals in my area. So I went out and purchased a Radio Shack amplifier like this (http://www.radioshack.com/product/index.jsp?productId=2103094&cp=2032057.2032187.2032188.2032195&allCount=24&fbn=Type%2FAmplifiers&f=PAD%2FProduct+Type%2FAmplifiers&fbc=1&parentPage=family). I only installed the indoor unit while leaving the outdoor part in the box. Once installed I received perfect reception on all three locals for over a week now.

All of a sudden this morning I could only get 1 of the 3 stations. I checked out the indoor amp and the red light was off indicating that I had a short between the 4221 and amp. I proceeded into the attic and disconnected the small transformer on the antenna and the light immediately came back on. So I changed out the transformer with another and the got the same results. A short.

What could be causing this to happen and how can I fix it?

AntAltMike

12-24-05, 01:51 PM

Surprise, surprise! The little "thingie" that came with your amplifier that looked like a balun or matching transformer is actually a mast-mounted preamplifier. Your base unit contains a distribution amplifier and a power supply for the mast-mounted preamplifier.

The baluns you are using suck down the pre-amplifier voltage and eventually lead to failure. Ideally, you still have the mast-mounted preamplifier and can insert it in place of the balun. If you do not, then you at least need to insert a voltage blocking coupler (often called VBC) between the power supply and the balun. If you do that, you will at least have the benefit of a noisy distribution amplifier, but it won,t be as good as a mast mounted amp.

firemantom26

12-24-05, 02:00 PM

It is surely easier for firemantom26 to swap the two leads on one of his baluns than to physically rotate one entire antenna. Also, he should make sure that he is using two physically identical baluns.

The vertical spacing between those two 8-bay bowtie antennas is relatively unimportant. Some people try to make sure that the spacing between the top bowties on the bottom antenna and the bottom bowties on the top antenna is the same as the vertical spacing of the bowtie elements within each antenna, and I think that might require that the screens overlap a little.

I switched the wires around today, and it works perfect. Does anyone have input on running a dual Channel Master amp?

TVSaurus

12-24-05, 02:45 PM

Surprise,surprise! The little "thingie" that came with your amplifier that looked like a balun or matching transformer is actually a mast mounted preamplifier. Your base unit contains a distribution amplifier and a power supply for the mast-mounted preamplifier.

The baluns you are using suck down the pre-amplifier voltage and eventualy lead to failure. Ideally, you still have the mast-mounted preamplifier and can insert it in place of the balun. If you do not, then you at least need to insert a voltage blocking coupler (often called VBC) between the power supply and the balun. If you do that, you will at least have the benefit of a noisy distribution amplifier, but it won,t be as good as a mast mounted amp.

I'm a little confused (newbie) so bare with me.

I kept the CM balun that came with the 4221 in-place when I initially installed the RS indoor amp box. I never used the pre-amp that came with the RS kit. However, I did use it when I realized the CM one didn't work and as mentioned above I got the same results.

So exactly what do I need to replace to get my signal back?

Neil L

12-24-05, 03:02 PM

Using just the indoor power supply without the pre-amp may have damaged the power supply, so that it is not working properly now.

holl_ands

12-24-05, 03:12 PM

Balun ID question?

I looked at the Excel from above, I've had the Phillips balun on a CM4228 for a year. My PBS station has always been iffy, I hope getting a db or two more of signal to my tuner will help.

I bought the antenna from another AVS member, who said it had little use, I don't doubt it.

I swapped out the balun that came with it, no ID, just says MAde in China, for the Phillips, thinking newer would be better. Now I wonder if I have a better balun sitting here in my parts bin, so my question is "How can I id this balun as a CM balun?"

Again, it is stamped, Made in China, nothing else.

Physically, the barrel or body has 2 grooves, the output nipple is 'flattened' on one side, and the 2 input wires seem to be a bit heavier gauge than the Phillips unit has.

Here are pictures of the "Made in China" balun that came from a recently purchased CM-4228.
I have not (yet???) measured the loss of this particular balun, but it's probably acceptable.

The CM Balun that I did measure was the similar (identical?) Model 3075, ordered from www.outpost.com as Fry's P/N 2570351.
[It's currently in my son's attic with a CM4221, soon to be upgraded with the CM4228.]
They are both about 3/4-inch diameter, which is somewhat larger than other manufacturers,
and have a lip on the round "rear" end that allows a plastic sleeve (not shown) to seal around the connector.

PS: I've been doing an indoor comparison of CM4228 (hands down winner) to the DX DTA-5000 Smart Antenna (about as good as a 4-Bay).
In a permanent installation, the balun should be secured so that it doesn't shift position in the wind (or earthquakes).

TVSaurus

12-24-05, 03:28 PM

Using just the indoor power supply without the pre-amp may have damaged the power supply, so that it is not working properly now.

so if I get another RS amp and use the RS supplied pre-amp I should be okay?

ctdish

12-24-05, 03:36 PM

Try the RS preamp you have now if the light on the indoor part stays on it is probably OK. John

pyedog

12-24-05, 03:37 PM

I am a noob with HD local channels and antennas. I currently have directv but I want my locals in HD so I am in need of an OTA antenna. I live on Beale AFB and antennaweb.org says I'm roughly 60 miles from the towers in Sacramenta, CA. For me to receive local channels in HD can I use an amplified indoor antenna or do I need to buy a more expensive outdoor antenna?

The TV5 was terrible for me, and I'm 25-40 miles from my towers. At 60mi you probably won't be happy with an indoor antenna ... just make sure you can return the indoor antenna if you try it.

A CM4228 should be around $50 or less (depending on where you get it and shipping). You might need a preamp as well (but probably not unless you have a long cable run), but an unamplified CM 4228 will probably get you a better signal than any amplified indoor antenna.

Good luck!

TVSaurus

12-24-05, 03:45 PM

Try the RS preamp you have now if the light on the indoor part stays on it is probably OK. John

I did. The light immediately went out just like with the balun.

holl_ands

12-24-05, 03:46 PM

I'm a little confused (newbie) so bare with me.

I kept the CM balun that came with the 4221 in-place when I initially installed the RS indoor amp box. I never used the pre-amp that came with the RS kit. However, I did use it when I realized the CM one didn't work and as mentioned above I got the same results.

So exactly what do I need to replace to get my signal back?
I just checked for DC shorts on coax output for the five outdoor baluns and 2 indoor baluns that I previously reported loss measurements.
Those that did not cause a DC short included the Philips, Radio-Shack (Gold and silver), RCA and both indoor baluns.

Only the Channel Master Balun that came with a CM-4228 antenna caused a DC short on the coax line,
which would cause problems for any DC power insertion device on that coax.
I have not checked the CM Balun from Fry's that was tested earlier, but it appears to be similiar (if not identical)
and hence may also cause a DC short on the coax line.

The cure is to either to remove the DC Power Insertion Module....which reduces loss by a few tenths of a dB....
or install a DC Block to prevent the DC voltage from being shorted out by the Balun,
e.g. R-S 15-1259 or GC BS-20 Voltage Blocking Coupler (www.outpost.com or Frys P/N 2420570).
Of course, they may increase the loss by a couple tenths of a dB.

AntAltMike

12-24-05, 03:55 PM

so if I get another RS amp and use the RS supplied pre-amp I should be okay?

The Radio Shack base unit and preamp you bought were a matched pair. Another off-the-shelf Radio Shack amplifier will not have an output voltage for the preamp.

Do you have a voltmeter? That will tell you whether your base uit is still sourcing voltage to the preamp, but I don't know whether that product uses AC or DC. In either case, it would be around 16 to 18 volts.

Are you sure you have identified the preamplifier that came with the amplifier? I think it is encased in soft, flexible vinyl, but I haven't seen one in years.

Also, make sure that there are no splitters in the coax that goes from the base unit to the preamplifier.

Tatmtt2120

12-24-05, 04:37 PM

The TV5 was terrible for me, and I'm 25-40 miles from my towers. At 60mi you probably won't be happy with an indoor antenna ... just make sure you can return the indoor antenna if you try it.

A CM4228 should be around $50 or less (depending on where you get it and shipping). You might need a preamp as well (but probably not unless you have a long cable run), but an unamplified CM 4228 will probably get you a better signal than any amplified indoor antenna.

Good luck!

Thanks, I went to fry's today to buy the CM4228 but they were sold out so I bought a CM stealth 3010 instead. Hopefully this one will work fine.

TVSaurus

12-24-05, 06:54 PM

The Radio Shack base unit and preamp you bought were a matched pair. Another off-the-shelf Radio Shack amplifier will not have an output voltage for the preamp.

Do you have a voltmeter? That will tell you whether your base uit is still sourcing voltage to the preamp, but I don't know whether that product uses AC or DC. In either case, it would be around 16 to 18 volts.

Are you sure you have identified the preamplifier that came with the amplifier? I think it is encased in soft, flexible vinyl, but I haven't seen one in years.

Also, make sure that there are no splitters in the coax that goes from the base unit to the preamplifier.

I'll have to go the voltmeter route after Christmas due to time limitations.

I've ID the preamp with the RS amplifier as a matching amp and it looks identical to the balun that came with the 4221. All in hindsight though.

No splitter just straight coax from the balun to the RS amp base unit.

ctdish

12-24-05, 07:45 PM

I have got an RS preamp here and although in can replace a balun electrically. It is considerably bigger than any balun I have seen. It is about 3" long 1 3/4 " wide and about an inch thick. It also has about 15 inches of 300 ohm lead coming from one end. John

newsposter

12-24-05, 10:13 PM

Sregener,

Power grid reliability may be fine, even if it's spewing a boatload of rf garbage into the air...and I suspect that's what is happening to you. Remember, as analog cell phones and other analog devices get turned off in 2009 (it won't be just DTV!), you may get a little less interference, especially as the stations go to even higher power. Don't rule out reliability just yet...there are too many variables
between now and February, 2009 (if that date holds).

HOLD on a minute...you mean my nice old ericsson phone that gets analog and digital wont be analog after the switch off? Then how will I get reliable signal on the desolate parts of the PA turnpike? I doubt they are going to get enough digital coverage to cover the analog they have now....then again I can hope

AntAltMike

12-24-05, 11:24 PM

I just checked for DC shorts on coax output for the five outdoor baluns and 2 indoor baluns that I previously reported loss measurements.

I have not checked the CM Balun from Fry's that was tested earlier, but it appears to be similiar (if not identical) and hence may also cause a DC short on the coax line.

The cure is to either to remove the DC Power Insertion Module....which reduces loss by a few tenths of a dB.... or install a DC Block to prevent the DC voltage from being shorted out by the Balun,

But if a balun that does not directly short the 75 ohm input consists primarily of a couple of parallel chokes straddled by a capacitor, then a short would still develop when a dipole is connected to its 300 ohm leads.

The cure is to replace the preamplifier module. Without it, you are left with a $60 distribution amplifier with a noise figure of probably around 6dB.

sebenste

12-25-05, 01:45 AM

Ding ding ding! Let's get it on!

A guy I know gave me his AP-8275 to test on my two antenna systems. I am located 60 miles west of Chicago, in a one-story townhouse with all antennas up in the attic, while my house sits low near the edge of a river valley.

One antenna system consists of a ChannelMaster 4228 8-bay UHF and a large Winegard VHF-only antenna that Winegard no longer makes. The second antenna system has a CM 4228 UHF antenna, but with a Radio Shack VU-90 suburban VHF antenna as part of it. The first system is diplexed with a CM 7777 preamp. The second/latter, I use a VHF-UHF diplexer, the output of which runs to an el cheapo 24 dB gain amplifier from Farm and Fleet (hardware store---think 'Home Depot' for farmers). All runs use RG-6 quad-shielded cable.

Well, tonight after I got back from Christmas services I decided to try this borrowed puppy out. This was a critical test! I looked at all the analog and digital stations, so I could see what the reception was. Then, I headed for the attic.

The combatants:

Reigning champion: ChannelMaster 7777 preamp on first antenna system
Specs: 23 dB gain VHF, 28 db gain UHF. Noise: 2.8 dB VHF, 2.0 dB UHF

Reigning champion: 24 dB gain no-name amplifier on second antenna system
Specs: 24 dB gain. Noise: 4 dB.

One thing I immediately noticed was that the Winegard AP-8275 doesn't have a separate VHF-UHF input option like the CM 7777 does. That means I have to take
off the combiner from my second system and run the cables from my first system to it to get it to work. That's not trivial, since that will make me lose a couple of dB of gain (not to mention it's 10 degrees up there, and doing this was a pain!). Well, I did it anyway...hooked up the Winegard preamp, with 50' of cable
between the powered amp and preamp in the attic...ran a jumper from the powered part of the amplifier to the TV, which was a 3' long cable...and saw the following.

There was a slight improvement in the VHF signals (2, 5, 7, 9, 11 analog from Chicago, and slight improvement with WBBM-DT on channel 3, but not enough to lock, sadly). The extra 6 dB you got from the Winegard amp on VHF was noticeable here, even with the 1-2 dB loss from the VHF-UHF combiner. OK, what about the UHF side? Both the CM 7777 and the Winegard AP-8275 claim 28 dB signal gain. It looks like that without a 1-2 dB signal loss from the combiner, the reception was going to be the same. The real-world pictures on UHF were a bit less, again, due to the combiner adding loss. OK, well, since most of the signals I want are on UHF, that stinks. So, I put the CM 7777 back on the first antenna system.

How about the second antenna system? The second one provides me with a more stable picture on WLS-DT in Chicago, so maybe that would help here. I connected the combiner again, sent the output to the Winegard preamp, and...

Nothing.

Back downstairs, the light on the powered portion of the preamp wouldn't even come on! Thinking I had a short, I checked the connections. Nothing wrong. Did I connect something backwards? Nope. I disconnected the AP-8275 and plugged in the no-name noisy signal amplifier. Bingo. Right back to where I started from, with a good picture from various stations. Did the AP-8275 fry or something? After trying it on shorter cable from a test antenna back downstairs where it was warmer, the answer was...no, because it worked! After thinking about it, I realized that my cable from the second antenna system to the TV was longer...maybe 75'. As it turns out, as far as *I* can tell, this particular preamp unit, if nothing else, couldn't handle the longer cable run. Why, I don't know. Tested twice on shorter runs on two antenna systems, it worked fine.

So, in summary, I can't recommend the Winegard AP-8275 to anyone with a cable run over 50'. That, and if you use separate VHF/UHF antennas in a rural area, the CM 7777 is superior on UHF and is close on VHF. Since most DTV stations are on UHF, the latter is most important, so the 7777 wins. In spite of having a reputation for handling power surges and lightning better, if it doesn't work, it doesn't matter! I'm returning my borrowed AP-8275 to its owner, disappointed.
I put a surge protector on the 7777 but still power the thing down during thunderstorms. And I'll be a happy CM 7777 user for a long time to come.

This is my experience, and mine only; your mileage may vary. I know, I've seen people use the unit with long cable runs. Why mine didn't work, I don't know.

Sirchadwick

12-25-05, 02:38 AM

I see several postings in reference to the Rat Shack products, and would like to inform that these products are BELOW standards and should not be purchased.

Stick with the Channel Master or Wineguard.

DR_LaRRY_PEpPeR

12-25-05, 07:13 AM

sregener, or anyone else, I tested the shortened 91XG yesterday (front 1/3 removed). Any reduction in directionality didn't make much difference. Just that the one off-axis channel that I couldn't get before the 7777 might've gotten a notch stronger. Still not better than the R-S though. :o

Thanks for the report sebenste. I've seen it mentioned many times about surges and lightning with the CM pre-amps. Are they really sensitive, and I should put mine on a surge protector? I'm assuming the power supply for surges, and the actual amplifier for lightning? (Or do you guys mean surges on the power supply CAUSED by lightning?)

Here are pictures of the "Made in China" balun that came from a recently purchased CM-4228.
I have not (yet???) measured the loss of this particular balun, but it's probably acceptable.

The CM Balun that I did measure was the similar (identical?) Model 3075, ordered from www.outpost.com as Fry's P/N 2570351.
[It's currently in my son's attic with a CM4221, soon to be upgraded with the CM4228.]
They are both about 3/4-inch diameter, which is somewhat larger than other manufacturers,
and have a lip on the round "rear" end that allows a plastic sleeve (not shown) to seal around the connector.

Thanks for the Outpost item number. :) I see their shipping is almost 3x the balun cost also. :( They should send these little things by USPS! Do you know of any other place to get them?

2 more questions: I guess the models on the CM site and Wholesale Electronics (www.weisd.com/store2/CM%207990.html) (0090/7990) are similar, if not identical, to what you tested? Finally, do the CMs just have bare wire twin-leads, instead of "spades" like most?

Tower Guy

12-25-05, 10:51 AM

I'm curious, what advantage does a vertical component offer? I'm thinking that is why a X works good as a VHF antenna, and rabbit ears work good (often better) at 45 degrees than at 90 degree as a true dipole. But still don't understand why a broadcaster would choose one way or the other on the vertical component.

Circular polarization (both H-pol and V-pol) tends to yield stronger signals with indoor rabbit ears and loop antennas. These tests were done with analog TV. Part of the advantage is the higher transmitter power that the FCC allows to make the H-pol signal the same. Theoretically, there's no advantage for C-pol when using a standard outdoor antenna.

Studies were done in the late 1940's that proved that H-pol has less ghosting than V-pol. That's why TV evolved as H-pol. I've measured V-pol reflections that were 10 db stronger than H-pol reflections.

With the marginal multipath performance of some DTV receivers, the use of elliptical or circular polarization for the DTV transmitter antenna does not make sense to me.

etcarroll

12-25-05, 12:18 PM

Thanks for the pics, that's what I have. I assume its performance should be equal to the 3075, so I'm going to reinstall it and see what becomes of the signal of my worst, (PBS), channel.

Here are pictures of the "Made in China" balun that came from a recently purchased CM-4228.
I have not (yet???) measured the loss of this particular balun, but it's probably acceptable.

The CM Balun that I did measure was the similar (identical?) Model 3075, ordered from www.outpost.com as Fry's P/N 2570351.
[It's currently in my son's attic with a CM4221, soon to be upgraded with the CM4228.]
They are both about 3/4-inch diameter, which is somewhat larger than other manufacturers,
and have a lip on the round "rear" end that allows a plastic sleeve (not shown) to seal around the connector.

PS: I've been doing an indoor comparison of CM4228 (hands down winner) to the DX DTA-5000 Smart Antenna (about as good as a 4-Bay).
In a permanent installation, the balun should be secured so that it doesn't shift position in the wind (or earthquakes).

holl_ands

12-25-05, 08:28 PM

Thanks for the Outpost item number. :) I see their shipping is almost 3x the balun cost also. :( They should send these little things by USPS! Do you know of any other place to get them?

2 more questions: I guess the models on the CM site and Wholesale Electronics (www.weisd.com/store2/CM%207990.html) (0090/7990) are similar, if not identical, to what you tested? Finally, do the CMs just have bare wire twin-leads, instead of "spades" like most?

ACE Hardware, True Value and Lowes are listed on CM site as distributors.
You can also search your locality for additional distributors:
http://www.channelmaster.com/home.htm
Call around....unfortunately, in our area the listed distributors only carry a few selected antennas.
They also list the usual on-line sources.

Both CM Baluns that I've seen have bare wires.
If you want spades, it's easy to crimp some on....
Preferably followed with solder...to avoid corrosion buildup over the years.

AntAltMike

12-25-05, 09:24 PM

holl_ands

12-26-05, 02:17 AM

Why does DR_LaRRY_PEpPeR believe that the Channel Master balun is any better than whatever else he might be using? The post distinguishing it from the other baluns tested was only to point out that electrically, it did not short a power supply, which is irrelevent to any valid circuit configuration.

I think that Channel Master makes all its outdoor baluns the same diameter so that they will fit into the balun mounting clips they furnish with their antennas. FWIW, holl_ands and I have both measured lower losses with narrower-body, indoor baluns. If you use an indoor balun outdoors, you should cover it with "coax seal", otherwise water can leak into the end where the flat, twin lead enters it.
In DR_LaRRY_PEpPeR's post, he provided link to my comparison test:
http://hdtv.forsandiego.com/messages/1/2489.html
Note that the maximum loss value for the CM balun was much less than any of the other outdoor baluns.

Of the baluns at hand for testing, the one with the lowest loss was actually the RMS CA-2100B, intended for indoor use.
Feel free to post any comparison results of your own....there isn't much to be found on this subject.

FYI: Here are results posted in hdtvprimer for CM0090 and two R-S balun models
and the (extremely high loss) found in the KYES test for a back-to-back Philmore/Pfantone combination:
http://www.hdtvprimer.com/ANTENNAS/basics.html
http://www.kyes.com/antenna/balun.html

DR_LaRRY_PEpPeR

12-26-05, 07:13 AM

Yeah, that's why I believe the CM balun would be better Mike. ;) But, I forgot that HDTV Primer had the loss chart (w/ 0090). :o Wow, those results are different than yours holl_ands... The R-S isn't doing too bad. Then again, it doesn't say how the results were obtained, so I'll tend to believe yours more. :)

The problem with the CM site's distributor list is, as you know, it doesn't list WHAT products they sell. Like Lowes here only has one big combo antenna and a 5' mast. :D I did find Skywalker Communications near here -- I'd seen it listed before, but couldn't browse their products. I figured out the guest login ( :rolleyes: ) and found the CM 0089 (no S-clip) for only $0.99 (www.skywalker.com/Dealers/Catalog/index.asp?ID=8244&Header=Satellite+and+Antenna+Products&Cat=Antennas&SubCat=Antenna+Accessories&Page=4)! (View after entering user/pass sw/2savemore.)

About the spades: just seems to make a nicer connection than wrapping bare wire around the antenna terminals. I found these (www.radioshack.com/product/index.jsp?productId=2103504&kwCatId=2032058) and these (www.radioshack.com/product/index.jsp?productId=2103393&kwCatId=2032058) at R-S. The first ones look exactly like what's on the R-S baluns, so they'd probably work.

sebenste

12-26-05, 09:06 PM

firemantom26

12-26-05, 11:52 PM

It is surely easier for firemantom26 to swap the two leads on one of his baluns than to physically rotate one entire antenna. Also, he should make sure that he is using two physically identical baluns.

The vertical spacing between those two 8-bay bowtie antennas is relatively unimportant. Some people try to make sure that the spacing between the top bowties on the bottom antenna and the bottom bowties on the top antenna is the same as the vertical spacing of the bowtie elements within each antenna, and I think that might require that the screens overlap a little.

I did switch the the two leads and it helped out. I do have the the spacing between the top bowties on the bottom antenna and the bottom bowties on the top antenna is the same as the vertical spacing of the bowtie elements within each antenna. I just was told it should be around 36 ins. I want to know if anyone else has tried this and what their results was.

Thank You

GilWave

12-27-05, 12:03 PM

I live among some hills in rural Northeast NJ, and we cannot get local television (or radio fo rthat matter) via TV antennas, so most of us have either cable TV (CableVision) or Direct TV.

At my house, a DirectTV site survey found that I can't even get Satelite reception :(

So, here's my dilema - my guest room has a nice HP Entertainment Center PC running Media Center. it's recording all my wife's favorite shows and soaps off the CableVision STB. I want it to record HD contecnt, but Microsoft in its infinite wisdom only allows for OTA reception of HD.

From what I've read here, indoor antennas won't cut it? What is my best bet for an antenna to get strong OTA HD reception? Any recommendations from folks similarly "out of range" would be appreciated.

-gil

TotallyPreWired

12-27-05, 12:35 PM

From what I've read here, indoor antennas won't cut it? What is my best bet for an antenna to get strong OTA HD reception? Any recommendations from folks similarly "out of range" would be appreciated.
How far away are you from the the transmitters(city?), and what is the terrain like between you and them?
.....jc

Neil L

12-27-05, 01:50 PM

we cannot get local television (or radio for that matter) via TV antennas.If you truely cannot get local analog stations at all (not even a snowy picture), then you probably don't have any hope of getting HDTV OTA. Have you ever tried to get analog TV with an antenna? Do any close neighbors get TV with an antenna? If so, what kind of antenna setup do they have? You may have a chance with a large antenna, on a tower tall enough to clear the trees and nearby hills.

GilWave

12-27-05, 03:08 PM

How far away are you from the the transmitters(city?), and what is the terrain like between you and them?35 miles Northwest of Manhattan (ABC, NBC, CBS), elevation is 1480 ft. above sea level. My house sits say half way down one of the mountains (which, in California, would be considered hills) just before a snall valley opposite another hill.

If you truely cannot get local analog stations at all (not even a snowy picture), then you probably don't have any hope of getting HDTV OTA.This is what I am afraid of. So the HD OTA signal is not higher power than good ole SD OTA?

You may have a chance with a large antenna, on a tower tall enough to clear the trees and nearby hills.That's the problem - even with a 40' tower DirectTV could not clear the trees.

So am I SOL?

bt-rtp

12-27-05, 03:09 PM

I would suggest that you call a small Mom-n-Pop type of local DirecTV authorized retailer in your area, you can find these in the Yellow Pages or in a strip mall near your neighborhood.

Explain your situation and ask them if they can send out their best technician to perform another site survey. Tell them that you will give them your business if they come through with a solution.

They will also likely be able to help you with an OTA antenna design based upon your structure, the distance and the obsticles in the area.

- bt-rtp

Neil L

12-27-05, 07:00 PM

35 miles Northwest of Manhattan (ABC, NBC, CBS), elevation is 1480 ft. above sea level. My house sits say half way down one of the mountains (which, in California, would be considered hills) just before a snall valley opposite another hill.I'm not familiar with the situation in NY, but 35 miles is not very far, unless of course those small mountains totally block the signal. And that may well be the case.So the HD OTA signal is not higher power than good ole SD OTA?Generally not. Most stations are going to try and cover the same geographical area with their digital broadcast as they are currently covering with analog. Some stations that are now using high UHF for digita are at higher power than they are for low VHF analog, but that is necessary to cover the same area, and won't help you any. BTW, most cable TV carry at least the HDTV signals from the major broadcasters, in the clear. So if you have even basic cable, you may be able to get HDTV on cable.

GilWave

12-27-05, 07:15 PM

So if you have even basic cable, you may be able to get HDTV on cable.I have cable, and get 18 HD channels. I have them downstairs on my SA 8300 HD. What I want to do is record OTA HD on my HP Entertainment Center upstairs, as Media Center does not record HD off cable.

Neil L

12-27-05, 08:05 PM

:o Oh yes, you did mention that in your original post, didn't you?:o

TotallyPreWired

12-27-05, 08:13 PM

:o Oh yes, you did mention that in your original post, didn't you?:o
No sh*t! 18 channels? Yup, you is hurting! :p

Well, does the 'Media Center' have component outputs? A little wire is a lot cheaper than an antenna system(if it's even possible).
....jc

GilWave

12-27-05, 09:42 PM

Well, does the 'Media Center' have component outputs? A little wire is a lot cheaper than an antenna system(if it's even possible).I'd need component IN to record HD from the cable box.

I assume Microsoft has an issue with HDCP so it will not take HD via cable.
:(

holl_ands

12-28-05, 02:49 AM

I have cable, and get 18 HD channels. I have them downstairs on my SA 8300 HD. What I want to do is record OTA HD on my HP Entertainment Center upstairs, as Media Center does not record HD off cable.
Only way to record encrypted HD channels is to rent an STB with IEEE-1394 Firewire port (e.g. SA3250HD and "some" SA8300HD's)
and record using either D-VHS or (I've heard) a MAC running DVHS Emulator.
http://www.avsforum.com/avs-vb/showthread.php?t=508907

A PC can only record the unencrypted SD/HD channels, either via Firewire interface or using a QAM tuner:
http://www.avsforum.com/avs-vb/showthread.php?t=403695
Microsoft is working on a new Media Center OPSYS that will accept encrypted input, but don't expect to see anything before 2007.

Tatmtt2120

12-28-05, 03:59 AM

sregener

12-28-05, 08:20 AM

I agree. My HD Dtv dish is pointed directly at a HUGE tree and I get 95% signal strength.

It's probably pointed *over* that tree. The dish is offset, meaning it is pointing higher than it appears.

Ku-band signals (which is what DirecTV and Dish use) do not penetrate leaves or pine needles.

GilWave

12-28-05, 08:49 AM

A PC can only record the unencrypted SD/HD channels, either via Firewire interface or using a QAM tuner. Microsoft is working on a new Media Center OPSYS that will accept encrypted input, but don't expect to see anything before 2007.Thank you holl_ands, that was what I needed to know. I prefer to use the nice elegant GUI interface from Media Center 2005, direct in from an OTA antenna (which most likely won't work due to my locale) or wait for Microsoft to work out the encryption. So it's SD on my HP PC for now. Acronym soup! :rolleyes:

sregener

12-28-05, 11:11 AM

Thank you holl_ands, that was what I needed to know. I prefer to use the nice elegant GUI interface from Media Center 2005, direct in from an OTA antenna (which most likely won't work due to my locale) or wait for Microsoft to work out the encryption. So it's SD on my HP PC for now. Acronym soup! :rolleyes:

I don't think your locale rules you out at all. You may need a good antenna, but properly mounted outdoors, I can't imagine you'd have any trouble getting the NYC digitals.

Get a Channel Master 4228 from someone who'll take returns and give it a shot. (more may be required for the digitals on VHF, but if you have success on UHF, the VHF should be a slam dunk.

I get reception from 75+ miles away, and my town is "down in a valley" and line-of-sight is impossible for almost all stations.

GilWave

12-28-05, 11:30 AM

I don't think your locale rules you out at all. You may need a good antenna, but properly mounted outdoors, I can't imagine you'd have any trouble getting the NYC digitals.Even if I can't get standard TV OTA in my locale?

Get a Channel Master 4228 from someone who'll take returns and give it a shot.Cool, I'll give it a shot - thanks!

sregener

12-28-05, 03:26 PM

Even if I can't get standard TV OTA in my locale?

When I moved to Rochester, MN, I was told, "Just get cable. You can't get anything here." So I did. a few years later, digital came along and I decided to give an antenna a shot. Lo and behold, the "nothing" I was supposed to get was flat-out wrong! I got better analog pictures from my antenna than what the cable company had. From my rooftop, I have 0 line-of-sight to any transmitters. I received digitals from 35 miles away *with no problems* 24x7. I received analogs from over 75 miles away just fine, although not perfectly.

In short, if you haven't put an antenna up, the "local wisdom" isn't worth a thing. Broadcasts are designed to cover at least 60 miles around the transmitter. Granted, you can get blocked by serious mountains, but last I checked, NJ doesn't have any of those. So you're probably dealing with some moderate hills. At 35 miles, that's nothing. At 55, I'd be worried for you.

Try it. Don't listen to the experts.

(Note: You will almost certainly need an outdoor antenna, and a preamplifier isn't a bad idea if your analog pictures are snowy.)

GilWave

12-28-05, 04:28 PM

In short, if you haven't put an antenna up, the "local wisdom" isn't worth a thing. Broadcasts are designed to cover at least 60 miles around the transmitter. Granted, you can get blocked by serious mountains, but last I checked, NJ doesn't have any of those. So you're probably dealing with some moderate hills. At 35 miles, that's nothing.Thank you - more good advice.

I'll try putting up the Channel Master and see how I do.

-gil

holl_ands

12-28-05, 04:29 PM

Thank you holl_ands, that was what I needed to know. I prefer to use the nice elegant GUI interface from Media Center 2005, direct in from an OTA antenna (which most likely won't work due to my locale) or wait for Microsoft to work out the encryption. So it's SD on my HP PC for now. Acronym soup! :rolleyes:
I just saw this this morning....seems things are getting better sooner than expected....
A Linux based Media Center from vwbinc that claims to now support CableCard input--giving access to encrypted and unencrypted cable channels.
http://www.vwbinc.com/press/122205pr.html

davefre99

12-28-05, 10:44 PM

I have sort of a unique situation were I have a local PBS affiliate that is just 8 miles from my location on UHF digital ch26 and analog ch24 that over power my distant (55+miles) signals off MT Wilson in the LA area. I currently have been using a cm4228 w/cm7775 preamp pointed almost exactly 90deg. off axis so I can null out the closer in signal that is about 4degrees off the main LA signals. IF I point the antenna straight at the LA towers I can get some of the channel on the higher end with signal levels near 90% but others in the lower band are just unusable. I found that inserting a 6db pad on the input side of the preamp and pointing off axis aprox 90 degrees I could virtualy get all the LA channels with a 60~80% signal most of the time. This has worked ok as a temporary fix but I am wondering if a different antenna that might have a narrower beam with might work better. I need something that has a 3~4 degree beamwith that will allow me to slightly null the close in signal and still point pretty much straight at the distant towers. My neighbors think I am crazy pointing my antenna completly away from the signal but there apparently is a very strong side lobe that allows it to work this way. I also have searched with no luck for a single channel trap that would let me just trap put the problem stations but so far I have come up with nothing.
Just for the record I live in Moreno Valley 92555 and antennaweb.org says I should not be able to get anything digital. I Posted a while back in the LA section but sort of just left things as they are for a while and now am getting the bug to try something else.
Dave,

holl_ands

12-29-05, 04:43 AM

Have you tried a Preamp with a much higher overload capability such as any of several Winegard 19dB gain UHF preamps
or the newer HDP-269 with an even higher overload resistance?
Or no preamp at all???

KVCR (analog and digital) are no doubt overloading the CM7775, which is why you need to point a null toward that direction
and accept whatever gain happens to be left towards Mt Wilson.

If you are looking for deep antenna nulls, horizontally stacked antennas may be useful.

sregener

12-29-05, 07:48 AM

davefre99

12-29-05, 11:30 AM

Have you tried a Preamp with a much higher overload capability such as any of several Winegard 17dB gain UHF preamps
or the newer HDP-269 with an even higher overload resistance?
Or no preamp at all???

KVCR (analog and digital) are no doubt overloading the CM7775, which is why you need to point a null toward that direction
and accept whatever gain happens to be left towards Mt Wilson.

If you are looking for deep antenna nulls, horizontally stacked antennas may be useful.

I tried a winegard 8700 pre-amp but it made things slightly worse. I am not sure if the winegard 4700 is better than the 8700 since it is uhf only but has much the same specs I believe. Also the 6db pad on the input should be degating the over drive shouldnt it. I have tried other combos of pads from 3db ~20db and settled on the 6db as it worked best. Where can I find the HDP-269 ?

davefre99

12-29-05, 11:37 AM

You shouldn't need a preamp for the Mount Wilson stations at 55 miles. The Mount Wilson antennas have line-of-sight for over 100 miles. I'd try removing the preamplifier altogether and make sure you actually need amplification. If you do, get a preamp with better overloading characteristics like the Winegard lineup holl_ands mentioned.

If you used a Channel Master Jointenna for channel 25, (and not attach the channel 25 input) that would give you a really strong filter on channels 24-26 on the primary antenna input.

I did try my cm4228 originaly with out the pre-amp and it would barely lock on a few channels even pointed straight at MT Wilson. THe pre-amp made an instant improvement but also causes my overload situation on the local signal.

Tell me more about the Jountenna. I am using one single RG-6 downlead, does it have dual inputs like a splitter combiner that filters/passes similar to a dc passive splitter and are thay available in specific channels? Who sells them I have never heard of them?

sregener

12-29-05, 11:38 AM

IAlso the 6db pad on the input should be degating the over drive shouldnt it. I have tried other combos of pads from 3db ~20db and settled on the 6db as it worked best. Where can I find the HDP-269 ?

You're probably getting somewhere between 20-40dB of extra signal from the local stations. That's a lot, as every 3dB = a doubling of power.

One place to get the 269 is here, but there are others: http://www.starkelectronic.com/allamps.htm

I still wonder if you really need a preamp to begin with...

bt-rtp

12-29-05, 03:25 PM

I'm planning to try out this modification (http://hdtvexpert.com/pages/cm3022.htm) to the Channel Master 4308 UHF Yagi-type antenna. It will be mounted on the roof of my two story house which is 15 miles from the tower with an unobstructed path. My desired frequencies are 49 thru 57.

Does anyone have any feedback to share, experiences or suggestions on these modifications ? http://hdtvexpert.com/pages/cm3022.htm

- bt-rtp

holl_ands

12-29-05, 03:44 PM

JoinTenna Info (about $30+s/h):
http://www.channelmaster.com/Pages/TVS/Passives.htm
http://www.warrenelectronics.com/Antennas/Jointennas.htm
http://www.hdtvprimer.com/ANTENNAS/GlossaryG.html

It is basically a two-way antenna diplexer/combiner, where the single channel input
goes through a narrow bandpass filter which attenuates all except the "chosen" channel.
The wideband all-channel input (the one you want to use) goes through a notch filter that is tuned for maximum attenuation of the visual carrier.
Note that you order it for a particular channel number, which requires the vendor to tune the filters for the desired UHF channel prior to delivery.

The all channel input also attenuates (to a lesser degree) adjacent channels (CH22, CH23 and CH25)
and will have only a small attenuation against CH21 and CH26.
Hence, you might want to consider inserting an additional JoinTenna tuned for CH26.
Unfortunately, the notch will only be effective against a relative small portion of the DTV signal spectrum,
which is spread across the entire 6 MHz channel allocation.

You might think that the analog CH24 (1320 kW peak power) would be more of an overload problem than digital CH26 (440 kW average power).
However, the PEAK power is what causes preamp overload (just like in any other kind of amplifier).
And the PEAK power of a DTV signal is about 7 dB higher (2200 kW peak power):
http://www.avsforum.com/avs-vb/showthread.php?p=6268128&highlight=peak#post6268128
http://www.avsforum.com/avs-vb/showthread.php?p=6273553&highlight=peak#post6273553
http://www.avsforum.com/avs-vb/showthread.php?p=6290253&highlight=peak#post6290253

==================================================
To give you an idea on how ineffective a single notch filter might be,
look at the attenuation curve for the following Eagle Notch Filter from tonercable:
http://www.tonercable.com/Toner%20Website/CatalogPages/SECTION%2016/EAGLELITE.pdf
Each horizontal subdivision is 1.5 MHz, so the notch will be very effective against the visual carrier,
but will have very little attenuation against the aural carrier located 4.5 MHz higher.
Fortunately, the station broadcasts the aural carrier (typically) 13 dB below the visual carrier for an analog NTSC signal.
Note that since the visual carrier is at the bottom of the NTSC channel (see picture),
the notch attenuates the lower adjacent channel much more than the upper adjacent channel.

================================================
You could accomplish a somewhat more effective attenuation (esp against DTV) by ordering double narrow-band notch filters.
Winegard UT-2700 (about $40+s/h) has two separate traps, one tuned for the visual carrier and the other for the aural carrier frequency.
This would be much more effective than a single trap, especially against a digital channel that does not have distinct energy peaks:
http://www.winegard.com/offair/trapsfilters.htm
http://www.epinions.com/content_190042771076
[Note that the picture is for a Mulitswitch, not the UT-2700.]
http://www.summitsource.com/product_info.php?ref=1&products_id=5344

Blonder-Tongue makes the (ouch, $220+s/h) MWT series of narrow-band notch filters that also have two separate tunable traps:
http://www.solidsignal.com/prod_display.asp?main_cat=5&CAT=&PROD=SS4614
http://www.starkelectronic.com/btc15-1.htm

===========================================
All of these filters claim to have a minimal 0.5 dB of insertion loss in the UHF band.

Original Hi-Tec

12-29-05, 04:05 PM

I am looking for a low profile outdoor antenna that will work the best 10 miles from the transmitter without a direct line of sight.

The two models I am looking at is the Radio Shack HDTV outdoor antenna and the Channel master Stealthtenna.

They both look fairly similar... but does anybody have an opinion why one might work any better then the other?

vivek9856

12-29-05, 10:26 PM

I want to install a new OTA antenna in my yard to recieve better local channels (High Def and Analog). Currently, I have a $20 RCA bunny ear antenna. I want a large outdoor antenna that is around 12' to 15', something to mount an antenna on (tripod/mount), and possibly a rotator. I am not sure if I need a rotator, but I was hoping you all could tell me if I need one. I want to keep the whole project under $200. If I could get it for less, that would be better.

This is currently what I thought I might get:
Antenna: Channel Master CM 3020 Deep Fringe Advantage TV Antenna
Channel Master CM 3679 Deep Fringe Crossfire Series Antenna
Radio Shack VU-190 XR
Channel Master CM 3018 Near Fringe Outdoor Antenna

Mounting System: Radio Shack 15-517 3-Foot Tripod Mount
Channel Master 30' Telescoping Mast

Rotator: Channel Master CM 9521A Complete Antenna Rotator Kit with Infra-Red Remote Control and 250 FT Rotator Wire

WVLA 33 NBC BATON ROUGE LA 252° 18.8 33
WGMB 44 FOX BATON ROUGE LA 252° 18.8 44
WGMB-DT 45.1 FOX BATON ROUGE LA 252° 18.8 45
WLFT-CA 30 IND BATON ROUGE LA 253° 5.2 30
WLPB 27 PBS BATON ROUGE LA 259° 13.9 27
WLPB-DT 27.1 PBS BATON ROUGE LA 259° 13.9 25
WBTR-DT 19 IND BATON ROUGE LA 283° 13.1 19
WAFB 9 CBS BATON ROUGE LA 258° 14.5 9
WAFB-DT 9.1 CBS BATON ROUGE LA 281° 12.7 46
WBRZ 2 ABC BATON ROUGE LA 239° 15.1 2
WBRZ-DT 2.1 ABC BATON ROUGE LA 239° 15.1 13
WBTR 19 IND BATON ROUGE LA 283° 13.1 19
K56DR 56 TBN BATON ROUGE LA 252° 18.8 56
WBXH-CA 46 BOX BATON ROUGE LA 311° 21.2 46
WBRL-CA 21 WB BATON ROUGE LA 283° 13.1 21
KBTR-CA 41 IND BATON ROUGE LA 287° 9.9 41
WSTY-LP 39 IND BATON ROUGE LA 342° 6.3 39
WNOL 38 WB NEW ORLEANS LA 114° 67.7 38
WUPL 54 UPN SLIDELL LA 95° 64.2 54
WMAU 17 PBS BUDE MS 10° 68.2 17
WVLA-DT 34.1 NBC BATON ROUGE LA 254° 7.6 34
WVUE 8 FOX NEW ORLEANS LA 115° 68.6 8
WWL 4 CBS NEW ORLEANS LA 120° 65.6 4
WPXL 49 I NEW ORLEANS LA 119° 65.8 49
WYES 12 PBS NEW ORLEANS LA 115° 68.6 12
KZUP-CA 19 IND BATON ROUGE LA 283° 13.1 19
WGNO 26 ABC NEW ORLEANS LA 114° 67.7 26
WLAE 32 PBS NEW ORLEANS LA 114° 67.6 32
KPBN-LP 11 A1 BATON ROUGE LA 285° 7.0 11
KATC 3 ABC LAFAYETTE LA 252° 87.1 3
KLFY 10 CBS LAFAYETTE LA 265° 78.2 10
KADN 15 FOX LAFAYETTE LA 266° 74.0 15
WDSU 6 NBC NEW ORLEANS LA 116° 68.3 6
WHNO 20 IND NEW ORLEANS LA 119° 65.8 20

davefre99

12-29-05, 11:01 PM

JoinTenna Info (about $30+s/h):
http://www.channelmaster.com/Pages/TVS/Passives.htm
http://www.warrenelectronics.com/Antennas/joiners.htm
http://www.hdtvprimer.com/ANTENNAS/GlossaryG.html

It is basically a two-way antenna diplexer/combiner, where the single channel input
goes through a narrow bandpass filter which attenuates all except the "chosen" channel.
The wideband all-channel input (the one you want to use) goes through a notch filter that is tuned for maximum attenuation of the visual carrier.
Note that you order it for a particular channel number, which requires the vendor to tune the filters for the desired UHF channel prior to delivery.

The all channel input also attenuates (to a lesser degree) adjacent channels (CH22, CH23 and CH25)
and will have only a small attenuation against CH21 and CH26.
Hence, you might want to consider inserting an additional JoinTenna tuned for CH26.
Unfortunately, the notch will only be effective against a relative small portion of the DTV signal spectrum,
which is spread across the entire 6 MHz channel allocation.

You might think that the analog CH24 (1320 kW peak power) would be more of an overload problem than digital CH26 (440 kW average power).
However, the PEAK power is what causes preamp overload (just like in any other kind of amplifier).
And the PEAK power of a DTV signal is about 7 dB higher (2200 kW peak power):
http://www.avsforum.com/avs-vb/showthread.php?p=6268128&highlight=peak#post6268128
http://www.avsforum.com/avs-vb/showthread.php?p=6273553&highlight=peak#post6273553
http://www.avsforum.com/avs-vb/showthread.php?p=6290253&highlight=peak#post6290253

==================================================
To give you an idea on how ineffective a single notch filter might be,
look at the attenuation curve for the following Eagle Notch Filter from tonercable:
http://www.tonercable.com/Toner%20Website/CatalogPages/SECTION%2016/EAGLELITE.pdf
Each horizontal subdivision is 1.5 MHz, so the notch will be very effective against the visual carrier,
but will have very little attenuation against the aural carrier located 4.5 MHz higher.
Fortunately, the station broadcasts the aural carrier (typically) 13 dB below the visual carrier for an analog NTSC signal.
Note that since the visual carrier is at the bottom of the NTSC channel (see picture),
the notch attenuates the lower adjacent channel much more than the upper adjacent channel.

================================================
You could accomplish a somewhat more effective attenuation (esp against DTV) by ordering double narrow-band notch filters.
Winegard UT-2700 (about $40+s/h) has two separate traps, one tuned for the visual carrier and the other for the aural carrier frequency.
This would be much more effective than a single trap, especially against a digital channel that does not have distinct energy peaks:
http://www.winegard.com/offair/trapsfilters.htm
http://www.epinions.com/content_190042771076
[Note that the picture is for a Mulitswitch, not the UT-2700.]
http://www.summitsource.com/product_info.php?ref=1&products_id=5344

Blonder-Tongue makes the (ouch, $220+s/h) MWT series of narrow-band notch filters that also have two separate tunable traps:
http://www.solidsignal.com/prod_display.asp?main_cat=5&CAT=&PROD=SS4614
http://www.starkelectronic.com/btc15-1.htm

===========================================
All of these filters claim to have a minimal 0.5 dB of insertion loss in the UHF band.

Very good information. If you had to guess which channel 24 anolog or 26 digital is more likely to be causing most of my problems. Or do you think I would need to filter both. At $30.00 a pop I would like to make an educated guess and try one at a time. My guess is that the digital signal is more important to filter out but I'm just guessing? I am also intiged with the idea of using a different pre-amp but my guess is being only 8 miles from a strong signal is going to be a problem for any amp?

holl_ands

12-30-05, 02:14 AM

Very good information. If you had to guess which channel 24 anolog or 26 digital is more likely to be causing most of my problems. Or do you think I would need to filter both. At $30.00 a pop I would like to make an educated guess and try one at a time. My guess is that the digital signal is more important to filter out but I'm just guessing? I am also intiged with the idea of using a different pre-amp but my guess is being only 8 miles from a strong signal is going to be a problem for any amp?
Unfortunately for you, BOTH are at high level...only a few dB difference....
I would call it about even when you also consider the different duty cycles.
Although the peak power for DTV CH26 was somewhat higher than analog CH24,
the latter has a much higher duty factor for those repetitive sync pulses.

A high gain Preamp (CM7775/7777, Spartan, AP8700, both B-T) is the absolute WORST choice for a Preamp from an overload point of view....
As was seen in the Overload Spread Sheet I posted as part of Santa Rosa DTV Fade Margin calculation:
http://hdtv.forsandiego.com/messages/1/2846.html#POST20070

The lower gain W-G AP4700 and HDP-269 are much better suited for use with nearby transmitters.
I updated the overload calculations for your location, assuming a -15 dB null directed towards San Bernardino.
[The antenna specs no doubt claim more than this, but I like to include backscatter signal pickup as a limiting factor.]

Despite the antenna null, high gain Preamps would be operating either close to or in excess of the spec overload point,
except for the low gain W-G AP4700 (or equivalent) and W-G HDP-269.

In order to maximize the Spurious Free Dynamic Range (SFDR), a Preamp needs to be operated with the maximum input signals well below the spec overload point (i.e. 15 to 20 dB below), as was discussed in the thread cited above.

The AP4700 calculations for your situation indicated that this derating would be somewhat marginal.
The HDP-269 would be a much better choice for a Preamp with a nearby transmitter.

penguin killer

12-30-05, 02:38 AM

So I currently own a Silver Sensor antenna to pick up local HDs here in a suburb of Seattle. According to the antennaweb.org site, the CBS, NBC, ABC affiliates are all roughly 16 miles away. The good news is that I can get them in with the silver sensor. If someone walks around in front of the antenna though, they go away. That's not a big deal.

My real problem is that I'm trying to pull in FOX which is about 35 miles away and is not at the same angle (249 versus 266). I'm able to get it in in spurts if I move the antenna, but I can never keep the signal for a consistent period of time. After reading the forums here, I thought I'd try attaching a CM 7777 pre-amp. No luck. I get the same results with and without the pre-amp. Based on my antenna web results, can anyone recommend anything I can do from an indoor antenna perspective that might work. Worst case scenario, I'll entertain outdoor antennas, but I'd really like to avoid that.

http://img525.imageshack.us/img525/1907/antresults7qb.th.jpg (http://img525.imageshack.us/my.php?image=antresults7qb.jpg)

Thanks.

holl_ands

12-30-05, 04:08 AM

That link is to the thumbnail. Deleting ".th" from the link yields the following:
http://img525.imageshack.us/img525/1907/antresults7qb.jpg

Yikes!!!! Transmitters are only 5.3 miles away.
OVERLOAD!!! OVERLOAD!!! OVERLOAD!!!!
A high gain Preamp, like the CM7777, is the absolute worst thing to do.

You could try a low gain Preamp, like the W-G HDP-269 or AP4700 discussed above,
but I would expect better results using a reasonable gain antenna (like CM4221, PR4400 or DB4)
mounted as high as you can get it.....either in the attic or better still on the roof.
Start by pointing towards about 255 degrees and hope that the nearby signals coming into the back of the antenna are not degraded too much.

If you have problems with the nearby transmitters and don't want to use a rotator, then you're looking at a dual antenna system with an RF Selector Switch.

If you want to try a dual antenna combiner instead of the RF switch, you might want to use antennas with narrower beamwidth to reduce multipath when they are combined.

DR_LaRRY_PEpPeR

12-30-05, 06:52 AM

I got the CM balun from the local place the other day, and I see it has solid wires which should attach nicely to my antenna terminals. The ones that come with spades (well, from RS at least) seem to be stranded, which is why I thought I'd want to add them. Anyway, I'll report any difference between the old RS balun and the new CM after I try it. :)

Just a quick question before I tidy-up my grounding stuff... is it OK to run the antenna/mast ground wire "through" the satellite dish's ground to avoid 2 wires? I assume so, since you can go "through" the grounding block, but want to make sure. The dish is only a couple feet away from where the antenna's wire would run anyway.

kezug

12-30-05, 09:25 AM

I live in NW Indiana and have gone to Antennaweb.org to get information regarding the stations I can pick up.

According to the results the large directional antenna (violet) gets me most of the stations from Chicago. However, it doesnt get me 2.1 for WBBM, but it does show that I can use a small directional antenna to get this. My question is this, according to the map rendered, the large directional encompasses the signal for WBBM small directional antenna...so will I get WBBM or not using a Violet for antenna type? (violet = large directional)

WYCC-DT 20.1 PBS CHICAGO IL 310° 34.1 21
* red - vhf WBBM-DT 2.1 CBS CHICAGO IL 310° 34.1 3
blue - uhf WXFT 60 TFA AURORA IL 308° 33.8 60
blue - vhf WBBM 2 CBS CHICAGO IL 310° 34.1 2
blue - vhf WGN 9 WB CHICAGO IL 310° 34.1 9
blue - uhf WCIU 26 IND CHICAGO IL 308° 33.8 26
blue - uhf WPWR 50 UPN GARY IN 308° 33.8 50
blue - uhf WSBT 22 CBS SOUTH BEND IN 91° 45.4 22
blue - uhf WJYS 62 REL HAMMOND IN 268° 35.8 62
blue - uhf WSNS 44 TEL CHICAGO IL 308° 33.8 44
blue - uhf WNDU 16 NBC SOUTH BEND IN 92° 45.7 16
violet - uhf WNIT 34 PBS SOUTH BEND IN 92° 46.5 34
violet - vhf WLS 7 ABC CHICAGO IL 308° 33.7 7
violet - vhf WMAQ 5 NBC CHICAGO IL 308° 33.7 5
* violet - uhf WMAQ-DT 5.1 NBC CHICAGO IL 308° 33.8 29
violet - uhf WOCH-LP 28 ETH CHICAGO IL 310° 34.1 28
violet - uhf WSJV 28 FOX ELKHART IN 92° 46.6 28
* violet - uhf WPWR-DT 50.1 UPN GARY IN 308° 33.8 51
violet - vhf WTTW 11 PBS CHICAGO IL 308° 33.7 11
violet - uhf WMWB-LP 25 WB SOUTH BEND IN 92° 47.0 25
violet - uhf WHME 46 REL SOUTH BEND IN 93° 48.3 46
violet - uhf WBND-LP 57 ABC SOUTH BEND, ETC. IN 92° 47.0 57
* violet - uhf WGN-DT 9.1 WB CHICAGO IL 308° 33.8 19
violet - uhf WFBT-CA 48 IND BLUE ISLAND IL 267° 39.5 48
violet - uhf WWME-CA 23 IND CHICAGO IL 308° 33.8 23

kezug

12-30-05, 09:28 AM

So if a Large Directional antenna is recommended (via antennaweb.org) than where do I find such an antenna?

kezug

12-30-05, 09:31 AM

Sorry for all the questions....

But once I do mount this antenna, can I feed it to my existing centralized location for my coax Cable feed (no cable signal) into all of my tv's throughout the house for non-digital signals just to pickup locals? Then I would pass the HD feed into my HDTV seperately.

Nothing is simple! But I am tired of paying Comcast and am looking for alternatives.

greywolf

12-30-05, 09:34 AM

Just a quick question before I tidy-up my grounding stuff... is it OK to run the antenna/mast ground wire "through" the satellite dish's ground to avoid 2 wires? I would. If you are concerned about building code compliance, contact your local building department. Codes vary.

hdtv4prs

12-30-05, 10:43 AM

I live about 40-45 south of the Cleveland transmiters and I am upgrading my 20 year old OTA antenna system since I have recently purchased a Sony HDTV. The 2 vhf stations are about 40 miles away and the farthest uhf stations are 45 miles north and 1 uhf station is 48 miles northeast. My 20 year old 160 " Radioshack vhf/uhf antenna is mounted on a 30' tower/rotor with a radioshack 30dB pre-amp. With 4 tv's ,a 2 way spliter, a 4 way spliter with a total of about 140' of coax cable that I counted in the system from the antenna to the network decribed.With my limited knowledge, I roughly estimated my cable and spliter loses at about 26dB(are these figures about right??). Read that you should add another 10 dB for other loses??. This would bring total loses at about 36dB ??

Looking at posts in this forum, it seems like the best quality antenna's and seem to be the Wineguards. The following are possible choices:
Wineguard HD 8200P or HD 7084P vhf/uhf antennas

Wineguard AP-8275 pre-amp
AP-8700 pre-amp

Channel Master 7777 pre-amp

What is a good choice for the antenna and pre-amp combination based on my present setup? Would I overload by getting too big an antenna or too high gain pre-amp? With My old antenna system , I Have picked up most of the HD programs that is listed from info from antennaweb.org. Some of the uhf stations have droped off at times and I haven't picked up some uhf stations at 45 miles.

Any suggestions/recommendations would be welcommed.

sregener

12-30-05, 10:58 AM

But once I do mount this antenna, can I feed it to my existing centralized location for my coax Cable feed (no cable signal) into all of my tv's throughout the house for non-digital signals just to pickup locals? Then I would pass the HD feed into my HDTV seperately.

Nothing is simple! But I am tired of paying Comcast and am looking for alternatives.

You need a VHF/UHF antenna to get all the stations you listed. And since they are scattered around you, you'll need a rotor, too. I'd look at the Winegard HD8200P with a preamplifier like the Channel Master 7777 or the Winegard AP-8275.

Under almost all circumstances, a larger than recommended antenna will not hurt you.

You can use your current wiring to distribute the signal from the antenna through the house. It should be okay. (Exception: if you have a lot of splitters, you may not get enough signal.) (Second exception: you must hook the preamplifier indoor unit before any splitters - so where the cable comes into the house. Splitters usually don't pass DC power, which is what the indoor unit pumps out to the outdoor unit.) You don't need separte wiring for HD reception.

sregener

12-30-05, 11:00 AM

Looking at posts in this forum, it seems like the best quality antenna's and seem to be the Wineguards. The following are possible choices:
Wineguard HD 8200P or HD 7084P vhf/uhf antennas

Wineguard AP-8275 pre-amp
AP-8700 pre-amp

Channel Master 7777 pre-amp

What is a good choice for the antenna and pre-amp combination based on my present setup? Would I overload by getting too big an antenna or too high gain pre-amp?

I vote for the 8200P and the 8275 preamp.

Unless you have a broadcasting tower (including FM) nearby, you don't have to worry about overloading.

davefre99

12-30-05, 11:27 AM

Unfortunately for you, BOTH are at high level...only a few dB difference....
I would call it about even when you also consider the different duty cycles.
Although the peak power for DTV CH26 was somewhat higher than analog CH24,
the latter has a much higher duty factor for those repetitive sync pulses.

A high gain Preamp (CM7775/7777, Spartan, AP8700, both B-T) is the absolute WORST choice for a Preamp from an overload point of view....
As was seen in the Overload Spread Sheet I posted as part of Santa Rosa DTV Fade Margin calculation:
http://hdtv.forsandiego.com/messages/1/2846.html#POST20070

The lower gain W-G AP4700 and HDP-269 are much better suited for use with nearby transmitters.
I updated the overload calculations for your location, assuming a -15 dB null directed towards San Bernardino.
[The antenna specs no doubt claim more than this, but I like to include backscatter signal pickup as a limiting factor.]

Despite the antenna null, high gain Preamps would be operating either close to or in excess of the spec overload point,
except for the low gain W-G AP4700 (or equivalent) and W-G HDP-269.

In order to maximize the Spurious Free Dynamic Range (SFDR), a Preamp needs to be operated with the maximum input signals well below the spec overload point (i.e. 15 to 20 dB below), as was discussed in the thread cited above.

The AP4700 calculations for your situation indicated that this derating would be somewhat marginal.
The HDP-269 would be a much better choice for a Preamp with a nearby transmitter.

Holl_ands
I do not fully understand the spreadsheets but I think you are suggesting that I would probably be best off using a an HDP-269 preamp and both ch 24,26 Antenna Jouners to obtain a -15db null on those close channels with my antenna pointed straight at MT Wilson instead of of Axis as I am doing now. If that would work then the cost would not be all that bad at just over $100.00 for everything. I wonder if the lower gain of the HDP-269 will stll be enough for the weaker distant channels from LA though.
At any rate thanks for all your input and at least I have a lot of options to think about.
Dave.

penguin killer

12-30-05, 12:55 PM

Tower Guy

12-30-05, 01:49 PM

So if a Large Directional antenna is recommended (via antennaweb.org) than where do I find such an antenna?

Warren Electronics, Moline, IL.

http://www.warrenelectronics.com/

holl_ands

12-30-05, 06:08 PM

Thanks for the help. I just want to make sure I understand what you're saying. So there are nearby transmitters 5 miles away, but they carry the channels I don't care about and the transmitter is located at a big angle difference from the transmitters I do care about. Does that impact anything you recommended? I do appreciate the help. Are the lower gain pre-amps still the best route?
Nearby transmitters are a difficult problem to overcome....or at least minimize the effects.
davefre99 uses a highly directional antenna (CM4228) to steer a sidelobe null towards the undesired nearby transmitter....and even then should be using the lowest gain Preamp in order to minimize the intermod distortion products in the Preamp and hence obtain the maximum dynamic range to (hopefully) receive the weaker signals.

In your case, you would be better off using an antenna with a fairly high Front-To-Back Ratio (F/B) and either no Preamp or the lowest gain WG HDP-269.

The CM4221 is an inexpensive starting point, with the CM4228 the next step up.
Even higher F/B is provided by the Antennas Direct 43XG and 91XG.
However, even with a high F/B ratio, the strong nearby signal will be bounced off of nearby buildings/hills into different azimuths on the antenna, so going all out for the best F/B will probably have diminishing returns on investment.

If you have an attic you want to use, you might be able to reduce the undesired signal (i.e. improve the F/B) by stringing up some chicken wire fencing (or whatever) between the antenna and the nearby transmitters.

So try what's inexpensive and preferably returnable first....

hoggy

12-30-05, 07:28 PM

holl_ands

12-30-05, 07:34 PM

Holl_ands
I do not fully understand the spreadsheets but I think you are suggesting that I would probably be best off using a an HDP-269 preamp and both ch 24,26 Antenna Jouners to obtain a -15db null on those close channels with my antenna pointed straight at MT Wilson instead of of Axis as I am doing now. If that would work then the cost would not be all that bad at just over $100.00 for everything. I wonder if the lower gain of the HDP-269 will stll be enough for the weaker distant channels from LA though.
At any rate thanks for all your input and at least I have a lot of options to think about.
Dave.
I did some more calculations, assuming you pointed the antenna towards MtWilson/SanBern.
The lower gain Preamp would probably still have problems picking up MtWilson due to intermods from SanBern.

I have a few more numbers to crunch (HDP-269 vs other Preamps) before I post it.

Suggest you start by ordering the JoinTennas (or preferably a pair of WG UT-2700 Dual Notch Filters).

TotallyPreWired

12-30-05, 07:39 PM

I'm in need of an indoor antenna for my hdtv. I would be purchasing it at best buy for several reasons, none of which are important. Can anybody give me an idea of what the best antenna that best buy sells for my application. I'de guess at most I am about 40 miles from Indianapolis tower. Thanks.
40 miles is asking a bit much for an indoor antenna. If you are going to spend the time and $$$ to try it, buy a CM 4228, and hang it on a wall. If it doesn't work, you can always put it where antennas belong, outside!
....jc

kezug

12-30-05, 08:20 PM

You need a VHF/UHF antenna to get all the stations you listed. And since they are scattered around you, you'll need a rotor, too. I'd look at the Winegard HD8200P with a preamplifier like the Channel Master 7777 or the Winegard AP-8275.

Under almost all circumstances, a larger than recommended antenna will not hurt you.

You can use your current wiring to distribute the signal from the antenna through the house. It should be okay. (Exception: if you have a lot of splitters, you may not get enough signal.) (Second exception: you must hook the preamplifier indoor unit before any splitters - so where the cable comes into the house. Splitters usually don't pass DC power, which is what the indoor unit pumps out to the outdoor unit.) You don't need separte wiring for HD reception.

You mention a VHF/UHF antenna with rotor to get these signals...but I also want to pick up some of the HD signals too. Is this a seperate antenna or is it all included with certain models?

kezug

12-30-05, 08:29 PM

I am sorry for posting this "off topic" here, but I value your opinions on this site, and quite frankly dont know where else to go to get a straight answer.

Since doing research for HDTV OTA and antenna's I have been pointed to several antenna web sites and came across a product I know I definitely need...and that is a good FM antenna. However, I am unsure of how to wire up this antenna to my stereos in my house. Now my stereos have COAX input for antenna FM at 75 Ohms)...is it as simple as connecting COAX to this antenna and feeding into my hub of cable wires in the basement...then splitting from my TV input to my stereo to get the FM signal?

Is it ok to have the FM signal running on the same cable that is also providing my Cable TV and Cable Internet? (I know it may be best to dedicate, but for SD and Internet is it ok to run FM too?)

Thanks.

TotallyPreWired

12-30-05, 08:31 PM

You mention a VHF/UHF antenna with rotor to get these signals...but I also want to pick up some of the HD signals too. Is this a seperate antenna or is it all included with certain models?
sregener can explain this. But there is no such thing as an HD antenna! :eek:
....jc

TotallyPreWired

12-30-05, 08:48 PM

kezug

12-30-05, 10:03 PM

sregener can explain this. But there is no such thing as an HD antenna! :eek:
....jc

Ok, ok...so I am sure I got funny looks on that question...but really...do I just use the UHF/VHF antenna to pick up the digital signals for HD?

TotallyPreWired

12-30-05, 10:20 PM

Ok, ok...so I am sure I got funny looks on that question...but really...do I just use the UHF/VHF antenna to pick up the digital signals for HD?
Yup. HD is being broadcast on both(depending on your locale) UHF and VHF. This is the very same as analog TV.

I'm not mocking you! Apparently the 'spin' on some aspects of HDTV have been quite effective!

Hey, if we add an HD in front of our model numbers, and tell the dummies that this is an HD antenna, we can charge more for it!

Good job Rosco, you're VP material my boy!
....jc

hoggy

12-30-05, 10:57 PM

40 miles is asking a bit much for an indoor antenna. If you are going to spend the time and $$$ to try it, buy a CM 4228, and hang it on a wall. If it doesn't work, you can always put it where antennas belong, outside!
....jc

I'm stuck with an indoor antenna for the time being and I know people much further away from sources that are getting signal with indoor antennas so I should probably be fine. I am still looking for a recommendation on something I can get at best buy, I have a gift card and there is nothing else from there that I need currently, plus I am an employee so the discount is big plus too.

Brian

bt-rtp

12-30-05, 11:27 PM

kezug,

Option 1 -- perhaps your cable company actually carries the FM stations on the cable system. Many do. Try this first. If they do, the station frequencies will be slightly re-arranged to work around problems with "direct pick up". (which is another subject). Their web site might have a station guide for this if so.

Option 2 -- Get an omni-directional FM antenna

This is available from Stark. Mount it inside your attic just under a high peak of the joists with a short piece of PVC pipe. From the balun (aka matching tranformer) on the antenna run a single dedicated RG-6 cable to your FM receiver. Fish it inside the walls if necessary. You can also use a splitter for multiple receivers. Do *not* combine this FM feed into a cable that is used for anything else such as Cable TV or satellite. That would be bad.

FM transmitter towers exist at numerous sites in all directions of various distances around a given reception location. You can easily research this on various web sites. This is beacuse FM services have a differnet usage model than TV. (lots of listeners in cars for example).

So as a result, FM reception is a very differnet situation than we have with OTA TV transmitter towers which are generally concentrated in one, or two, and potentially even three tower sites that are all within range of an "average greater metropolitan" fixed reception location.

TotallyPreWired

12-30-05, 11:31 PM

I'm stuck with an indoor antenna for the time being and I know people much further away from sources that are getting signal with indoor antennas so I should probably be fine.
Is there 'magic' in the air out there? Indoor, at 40 miles? :eek: Good luck!
...jc

sregener

12-31-05, 09:50 AM

I'm stuck with an indoor antenna for the time being and I know people much further away from sources that are getting signal with indoor antennas so I should probably be fine. I am still looking for a recommendation on something I can get at best buy, I have a gift card and there is nothing else from there that I need currently, plus I am an employee so the discount is big plus too.

Sorry to bust your bubble, but Best Buy isn't a good place to buy an antenna. If you *must* buy one there, and it *must* be an indoor model, your best bet would be the Terk HDTVA antenna. But it isn't very good. (Comparable to the Silver Sensor on the gain chart here: http://www.hdtvprimer.com/ANTENNAS/GlossaryG.html#indoor)

At 40 miles, you're really pushing things for indoor reception in most areas of the country. There are a few places (Florida and the Mount Wilson towers in LA come to mind) where it's doable, but for the rest of us, there isn't going to be anything but snow to pick up.

Your best bet is to get the largest bowtie model you can find and install it as high as you can. The Channel Master 4228 is the best choice, the 4221 second best, and the AntennasDirect DB2 would be a distant third. A low-noise, high gain preamplifier (Channel Master 7777) would probably help things a little. You're still expecting a miracle unless you're installing this in your attic.

None of these recommendations are available at Best Buy. Sorry to burst your bubble, but Best Buy is a terrible place to buy accessories like video cables, antennas, and the like. Their products are overpriced and rarely perform well. Their antennas may be the worst of the bunch.

sregener

12-31-05, 09:53 AM

Since doing research for HDTV OTA and antenna's I have been pointed to several antenna web sites and came across a product I know I definitely need...and that is a good FM antenna. However, I am unsure of how to wire up this antenna to my stereos in my house. Now my stereos have COAX input for antenna FM at 75 Ohms)...is it as simple as connecting COAX to this antenna and feeding into my hub of cable wires in the basement...then splitting from my TV input to my stereo to get the FM signal?

Is it ok to have the FM signal running on the same cable that is also providing my Cable TV and Cable Internet? (I know it may be best to dedicate, but for SD and Internet is it ok to run FM too?)

You can't combine Cable signals with VHF/UHF/FM signals. They overlap on frequencies, so you'll get nothing but trouble.

A good VHF/UHF antenna will also pick up FM just fine for most applications. Unless you're looking to do some serious DX work, you'll be fine with the FM reception from those antennas. As you suspected, just split off the antenna feed and run one section into your TV and the other into your tuner.

As others have stated, there is no such thing as an "HDTV" antenna. Digital television is broadcast on the same frequencies as analog, and an antenna is designed to receive frequencies; it doesn't care what type of signal is on those frequencies. In Cleveland, there are digital signals on both the UHF and VHF frequencies, so that's why I recommended a VHF/UHF combo antenna. In other markets, all the digitals are on UHF, so those areas can get by with just a UHF antenna.

hoggy

12-31-05, 11:08 AM

Is there 'magic' in the air out there? Indoor, at 40 miles? :eek: Good luck!
...jc

I check antennaweb.org and it says I'm about 36 miles from the transmitters most are concerned with. The people I know further away are about 10-12 miles further away.

I don't have the option of putting an antenna outside at this point in time.

I do have a question off topic a bit though. What are the differences between cable, sat, and ota HDTV picture quality. I know some satalite is really OTA and cable varies depending on provider, but I'm just wondering about it in a general sense.

Neil L

12-31-05, 01:46 PM

hoggy,
Generally, OTA has the potential for the best picture. Cable and sat. will usually do some "bit grooming" to make the data fit better into the bandwidth they have available. But, the quality differences may be so small that you will never notice. And then, were I am, most of the OTA broadcasters are using a reduced bit rate for their HDTV channels so they can multi-cast other channels using the rest of their bandwidth, and picture quality suffers. But if your reception is bad OTA, cable or sat. would probably give you a more reliable HD signal. A reliable signal might be better than spotty OTA, even if the bit rate is reduced.

kezug

12-31-05, 03:10 PM

bt-rtp

01-01-06, 01:42 AM

kezug,

Geez dude, this is a nickel/dime issue. Get off the pennies...

Drop the 20 bucks and throw the antenna in your attic. You will never regret it, especially at night when you receive stations far away from you in other major cities. Childs play....

newsposter

01-01-06, 01:49 PM

hoggy,
Generally, OTA has the potential for the best picture. Cable and sat. will usually do some "bit grooming" to make the data fit better into the bandwidth they have available. But, the quality differences may be so small that you will never notice.

Except in philly on directv. The locals on the bird are so bad, if i have a reliable OTA signal (only do on 4 networks), i even record SD stuff OTA on the tivo (taking up 5x the space of SD on satellite). Locals on dtv are that bad for me.

sregener

01-01-06, 05:03 PM

Except in philly on directv. The locals on the bird are so bad, if i have a reliable OTA signal (only do on 4 networks), i even record SD stuff OTA on the tivo (taking up 5x the space of SD on satellite). Locals on dtv are that bad for me.

I think they're asking about HD quality, not SD locals. Are you saying the MPEG4 HD locals from DirecTV are that bad?

powerusr

01-01-06, 05:49 PM

Hey Guys,

I am looking for the FCCs Grade B Signal Test or Contour Maps. I used to have it book marked but cannot find it now.

Thanks
p

blindowl1234

01-01-06, 06:19 PM

This should be the link or close to it.

powerusr

01-01-06, 06:54 PM

deconvolver

01-01-06, 07:57 PM

Thanks!

I found that one but it does does not give Grade Contours. There was one I found and did a Wayback Machine on http://web.archive.org/web/20040605135801/http://www.bsexton.com/ But it is dead now.

p
When I put in the call sign at this link:
http://www.fcc.gov/mb/video/tvq.html
and then click on a licensed result there are links to the service contour areas. I think the result for an NTSC licensed area may be the map that you are looking for.

powerusr

01-01-06, 11:02 PM

Thanks Guys.

Apparently not only am I dumb but I cannot see to well ether.

p

newsposter

01-02-06, 01:52 PM

would a jointenna help me in this situation? I read the warrenelectronics page but am unclear.

my uhf channels are 26 32 42 54 64 67

All are at 130 degrees except channel 42, at 128. I'm doing an in attic thing and have signals in the 80s for all channels but 42 and 54. At this point, I'm not worried about 54. But 42 is important to me. I took down the DB8 and tried other places in the attic. I can achieve a 68 signal but then the other channels drop to 70s or worse and dont inspire confidence.

So, if I get another antenna and aim that only for channel 42, do i just call warren and ask for a jointenna to receive channel 42? Then will that block channel 42 from the DB8 and only pick up channel 42 from my new antenna (will shop locally for return privledges). I just want to make sure before I do anything that this is how it works.

The antennas would be about 5 ft apart horizontally hanging from my attic rafters.

TotallyPreWired

01-02-06, 02:04 PM

would a jointenna help me in this situation?
That's what they are made for.

So, if I get another antenna and aim that only for channel 42, do i just call warren and ask for a jointenna to receive channel 42? Then will that block channel 42 from the DB8 and only pick up channel 42 from my new antenna (will shop locally for return privledges). I just want to make sure before I do anything that this is how it works.
Yup. The JT will also block or degrade a channel or two either side of the target channel(but it doesn't look to be a problem for you ;) ). Your cable will run from the DB8 to the JT, and from the new antenna to the JT. Then 1 cable to your TV/Distribution point. A preamp, if used, is added at the output of the JT.
....jc

gmarcotte

01-02-06, 09:10 PM

i have a dish network 811 box and the antenna that came with it is doing nothing, i was just wondering if i can use a cable to put this little antenna up in the attic and if so what kind of cable do i need. thanks

grady

ScottFern

01-03-06, 12:08 AM

Colm

01-03-06, 12:19 AM

ScottFern

01-03-06, 12:22 AM

I am assuming by display you mean monitor, as opposed to TV (no tuner built in). There is no such thing as an antenna that connects to HDMI. HDMI is a digital interface used to connect a tuner, DVR, or other device. You need a tuner (set top box, STB). The antenna connects to the STB via coaxial cable. The STB connects to the monitor via HDMI (if that is the interface you want to use).

Thanks for the quick response! Sorry, I am new to the HDTV/OTA field. You cleared up what I had confused. I guess I will stop by RadioShack tomorrow and see what they have.

holl_ands

01-03-06, 04:31 AM

Hello,

I just bought a Vizio P50PD 50" plasma and I was looking for the best indoor antenna that I can connect via HDMI to this display.

What do you experts at AVS recommend?? Also, is it even possible to buy an OTA antenna with a HDMI input?

Thanks!
Andrew
Google didn't know what a V, Inc Visio P50PD was....so I'm not sure what you have and whether it already has a built-in ATSC On-Air Hi-Def tuner.
If it is the Visio P50 HDM, then it is a Monitor without any built-in cable or on-air tuner. These would need a stand-alone On-The-Air STB.

The R-S Accurian HTS-6000 is very highly rated, but is being closed out for only $100, hence they are very hard to locate.

Wal Mart, Best Buy and Circuit City are more likely to have OTA STBs either in stock or available via on-line order.
The $200 models usually are ATSC only and won't tune the analog NTSC stations.
A full featured model will be closer to $300-350.

sregener

01-03-06, 09:11 AM

newsposter

01-03-06, 09:13 AM

That's what they are made for.

Yup. The JT will also block or degrade a channel or two either side of the target channel(but it doesn't look to be a problem for you ;) ). Your cable will run from the DB8 to the JT, and from the new antenna to the JT. Then 1 cable to your TV/Distribution point. A preamp, if used, is added at the output of the JT.
....jc

my uhf channels are 26 32 42 54 64 67

Thanks...now let me ask this (after playing around yesterday and getting the antenna out of whack)

is there any chance of having the db8 for all channels but 42 AND one of the channels 64 OR 67. It appears I now have problems and even though they are supposed to be in the same direction, when one is in the 80s signal the other one has problems in the 60s to 70s now. I know the best thing is to try to aim better but i cant seem to hit the spot again.

somehow i doubt i can isolate 2 channels but figured i'd ask

newsposter

01-03-06, 09:53 AM

Naylia

01-03-06, 10:01 AM

According to Radioshack.com, the Terk HDTV Amplified Indoor Antenna has been discontinued and they are now only carrying what stock they have in-store currently.

http://www.radioshack.com/product/index.jsp?productId=2110925&cp=&kw=terk&parentPage=search

Those of you in an area looking for indoor antenna may want to snag one now, you can find out which stores local to you have it still from the website above. If it is truly being discontinued by Terk hopefully we see an improved replacement from them.

EDIT: I can find't any mention on the Audiovox/Terk website that the product is discontinued...it's possible Radioshack may just no longer be carrying them.

TotallyPreWired

01-03-06, 11:07 AM

...is there any chance of having the db8 for all channels but 42 AND one of the channels 64 OR 67. It appears I now have problems and even though they are supposed to be in the same direction, when one is in the 80s signal the other one has problems in the 60s to 70s now. I know the best thing is to try to aim better but i cant seem to hit the spot again.

somehow i doubt i can isolate 2 channels but figured i'd ask
Ya mean like this:
http://www.panelcrafters.net/join-tenna-3.jpg

Sure, you can 'chain' more than 1 JT.
....jc

TotallyPreWired

01-03-06, 11:11 AM

Will it make any difference if an amp is between the 50 ft and 75 ft rg6 run versus having it right at the antenna pumping down the full 125 feet? ...i'm assuming the barrel connector between the 2 lines is negligible loss
Yes. 50'-75' of RG-6 probably has an attenuation loss of 2-4 dB depending on the quality of the cable. So, you want the preamp as close to the antenna as possible. I'm not saying that it won't work, just that it would work better if it's closer.
....jc

the_bear89451

01-03-06, 02:17 PM

I am seriously considering spraying my antenna with PAM. Is this a crazy idea?

I got so much snow on my antenna that it got moved out of alignment. The snow built up and out on each element. Eventually, the snow buildup on the individual elements began to touch. Now the whole antenna became a bed for snow to build up on. The antenna bent over pretty far and eventually snapped straight as the snow fell off, but now it’s pointed the wrong way and a little permanent bend.

newsposter

01-03-06, 03:00 PM

Ya mean like this:
http://www.panelcrafters.net/join-tenna-3.jpg

Sure, you can 'chain' more than 1 JT.
....jc

I like the pic and possibility...but i was thinking of just 2 antennas...one for all but channel 42 and 67or64....I'm thinking I can line up 42 and either 64 or 67 but 64 and 67 wont come in well at the same time. So if i can just aim one of them along with 42, it would work out pretty good

i guess i have the option in your picture but that's a bit more than i wanted to pay :)

silicon

01-03-06, 04:51 PM

I have gone through some pages here, also reviewed few web sites such as antennadirect etc and other forums, help pages to find which antenna is best for my HDTV reception.

I reviewed DB2, DB4 and few others PHDTV3, MANT510, ANT200, ANT1250.

ANT1250 and MANT510 looks amplified antenna with 45dB, 50dB respectively, can also receive VHF, UHF, HDTV. Verified ANT1250 is not so good (may be the one I tested is defective!)

PHDTV3 (Phillips) says 10 dB amplification, costs more than MANT510 which says 50 dB amplification. Is it better to go for PHDTV3 or MANT510?

I tried ANT1250 (RCA) which gets 9 channels with ATSC tuner. Not satified, I tried low end ANT200 (RCA) which is getting 19 channels.

Some place, people refer DB2 and DB4 are good. I can not go to DB4, but can go for DB2 (indoor only). With all these technical jargons about dB (decibel) amplification, I am confused a lot.

Experts, any help or review or feedback?

Thanks in advance.

Silicon

sregener

01-03-06, 05:35 PM

With all these technical jargons about dB (decibel) amplification, I am confused a lot.

Amplification is mostly marketing for indoor antennas. What really matters is gain, and they aren't exactly publishing those specs, are they? Once you've overcome line loss (minimal with an indoor antenna) and the noise factor of the receiver (at worst, 10dB for UHF) all amplification does is make things worse. And the amplifiers built into most indoor antennas are terrible because they introduce a lot of noise - something you don't want with digital reception.

The DB2 is the best indoor antenna out there. The DB4 would work indoors if you had a place you could put it, or even the DB8. The only thing keeping an outdoor antenna outdoors is when it doesn't fit indoors. When you get to the 15' long by 10' wide antennas, most people would prefer to keep that out of their living room, assuming they even have a 15'x10' living room.

TotallyPreWired

01-03-06, 07:21 PM

I am seriously considering spraying my antenna with PAM. Is this a crazy idea?
Yes. Although the eggs on Sunday morning won't stick to it! You could try sending 230 volts through it! :p
I got so much snow on my antenna that it got moved out of alignment. The snow built up and out on each element. Eventually, the snow buildup on the individual elements began to touch. Now the whole antenna became a bed for snow to build up on. The antenna bent over pretty far and eventually snapped straight as the snow fell off, but now it’s pointed the wrong way and a little permanent bend.
Weird, I've never really heard of that. I've got multiple antennas, and I've never had any snow build up. Satellite dishes, yes, but not on the antennas.

Do you have any Cottonwood trees in your area? If so, the antenna could end up looking like polar bear in the summer!

I'd just say no. I'm sure that after the PAM sits for a while in the weather, that it would either disappear, or get really sticky. Then again, you may have just invented the super antenna!
....jc

holl_ands

01-03-06, 07:30 PM

Jim5506

01-03-06, 07:45 PM

Will it make any difference if an amp is between the 50 ft and 75 ft rg6 run versus having it right at the antenna pumping down the full 125 feet? ...i'm assuming the barrel connector between the 2 lines is negligible lossIt could work, just remember that you are amplifying everything that comes into the input side of the amplifier, noise, static, RF, and any other junk that the cable picked up since the antenna injected the signal.

TheRatPatrol

01-03-06, 07:47 PM

the_bear89451

01-03-06, 11:42 PM

What kind of antenna was it????
So how much do you think was ice that then collected snow????

The antenna is a Funke PSP.1922, so the spacing between the elements is pretty big as well as the total length. The storm that hit the Sierras the past few days started out warm (rain) and then turned colder (snow). I think this combination of water already on the antenna freezing at the same time new snow was falling on it caused the buildup. While that weather pattern is unusual, it does happens a few times each year. I am somewhat amazed how close to straight the antenna bounced back to. I am now hit or miss with getting locks. Without LOS, I usually get a pretty strong signal once there are a few feet of snow on the ground, which I assume is caused by signal reflection. I have a metal roof, so I am in no hurry to straighten the antenna with snow up there. I also thought about trying a layer of WD40.

silicon

01-04-06, 01:01 AM

Amplification is mostly marketing for indoor antennas. What really matters is gain, and they aren't exactly publishing those specs, are they? Once you've overcome line loss (minimal with an indoor antenna) and the noise factor of the receiver (at worst, 10dB for UHF) all amplification does is make things worse. And the amplifiers built into most indoor antennas are terrible because they introduce a lot of noise - something you don't want with digital reception.

The DB2 is the best indoor antenna out there. The DB4 would work indoors if you had a place you could put it, or even the DB8. The only thing keeping an outdoor antenna outdoors is when it doesn't fit indoors. When you get to the 15' long by 10' wide antennas, most people would prefer to keep that out of their living room, assuming they even have a 15'x10' living room.

Thank you sregener, for the detailed information.

Silicon

BovineD

01-04-06, 04:29 AM

Does anyone have this antenna and if so how well does it work? Thanks.

First post here so hopefully I can add some info to these great forums. I actually was just about to post my personal OTA HD story and I see that a couple of people are asking about the Terk HDTVa amplified indoor antenna. I received my Directv HR10-250 unit the day after Christmas as I finally got the deal I had been chasing (150$ after instant rebates). Hooked it up to my 57" Hitachi RPTV with the DVI connector and was blown away by the HD picture. Selectable 480p/720p/1080i on the unit is awesome. After enjoying the free prgramming for about a week I started hunting for a good OTA connection for my location which is in Tracy, CA with the folowing antenna info:

* yellow - uhf KTXL-DT 40.1 FOX SACRAMENTO CA 338° 37.0 55
* yellow - uhf KVIE-DT 6.1 PBS SACRAMENTO CA 338° 37.0 53
* yellow - uhf KSPX-DT 29.1 i SACRAMENTO CA 338° 36.8 48
* yellow - uhf KQCA-DT 58.1 WB STOCKTON CA 341° 36.4 46
* yellow - uhf KOVR-DT 13.1 CBS STOCKTON CA 338° 34.9 25
* yellow - uhf KCRA-DT 3.1 NBC SACRAMENTO CA 339° 35.4 35
* green - uhf KXTV-DT 10.1 ABC SACRAMENTO CA 338° 34.9 61
* lt green - uhf KUVS-DT 19.1 UNI MODESTO CA 40° 46.8 18
* lt green - uhf KMAX-DT 31.1 UPN SACRAMENTO CA 340° 36.5 21
* red - uhf KTFK-DT 64.1 SAH STOCKTON CA TBD 275° 28.1 62
* blue - uhf KTNC-DT 42.1 AZA CONCORD CA 277° 27.4 63
* violet - vhf KNTV-DT 11.1 NBC SAN JOSE CA 251° 54.7 12

I immediately started to look for the Zenith Silver Sensor after reading about the great success people have had with it for indoor single level houses. My house is stucco wall with some insulation with my TV in the main living room with only one side of windows. I could not find a place to purchase the SS so I started mucking around the local radio shack and other brick and mortars for any decent UHF antennas to get a baseline for what kind of signals I would get.

I started with this model from BestBuy:

RCA ANT301 (Cant post links yet I guess...)

Avoid this stinker. I was barely able to get 40-50 signal strength on the closest towers and the signal was unwatchable. Returned unit

Next I went with a couple of generic units:

RCA RCA Amplified VHF/HDTV/UHF/FM Antenna, ANT1250

Philips Silver Sensor PHDTV3

First unit seemed slightly better giving around 60-70 on the signal strength but I had to move the unit from one location to a completely different location to received NBC and CBS correctly so that meant moving it around ALOT.

Second unit was by far the worst barely giving me 20-30 on the close towers. Might have picked up NBC once. Returned both units.

Getting desperate to view real OTA HD I went back to bestbuy after researching the Terk HDTVa antenna. Read alot about how Terks were overpriced and underpowered but I went ahead and grabbed one anyways. What could I lose at this point.

I noticed a huge improvement from the moment I hooked it up. With some fine tuning I was able to get 7 of 9 stations at 85 and above with the last two of WB and CBS givign really sporadic signals jumping from 10 to 80. Going to try and figure out why that is but FOX and NBC was what I really needed so i may just stay with this setup. I might still try a Zenith SS just to compare but 60 bucks for indoor OTA signals is fine by me. Hope this helps with anyone on the fence about this unit!

holl_ands

01-04-06, 05:07 AM

The antenna is a Funke PSP.1922, so the spacing between the elements is pretty big as well as the total length. The storm that hit the Sierras the past few days started out warm (rain) and then turned colder (snow). I think this combination of water already on the antenna freezing at the same time new snow was falling on it caused the buildup. While that weather pattern is unusual, it does happens a few times each year. I am somewhat amazed how close to straight the antenna bounced back to. I am now hit or miss with getting locks. Without LOS, I usually get a pretty strong signal once there are a few feet of snow on the ground, which I assume is caused by signal reflection. I have a metal roof, so I am in no hurry to straighten the antenna with snow up there. I also thought about trying a layer of WD40.
Yikes....the Funke site shows it as being a hi-band VHF Corner Yagi with 14 directors, folded dipole driven element and a reflector.....nearly 4 meters worth!!!!
http://www.funke.nl/prod_files/aerials/190_098502_psp1922_051203_790500985.pdf
At least it had conventional rods rather than X-shaped directors (e.g. 91XG)....they must be a real problem in snow country....

We don't have these kinds of problems, here in WD40's hometown.
FYI: "Prevents antenna from freezing during winter " -- From 2000 Uses for WD-40.
But doesn't say anything about snow buildup....I would worry about it getting gummy when sub-zero...
http://www.twbc.org/wd40.htm

Silicone, Teflon (Dupont) or PTFE (generic) spray lubricants are other options.....
The performance under sub-zero temps is important to know....
http://www.super-lube.com/product_description.htm
http://www.super-lube.com/Features_and_Appllications.htm
Super Lube Aerosol evaporates and leaves a film that is very slick and not sticky (my own experience confirms this).
They claim that it continues to be slippery, even in freezing temps. (I cannot confirm.)

I have a can of each type in the garage and would recommend you try a can of Super Lube PTFE Aerosol.

Naylia

01-04-06, 09:18 AM

Does anyone have this antenna and if so how well does it work? Thanks.

Just hooked it up last night...I am in the Boston aread roughly 6 miles from towers spaced between 217 deg and 225 deg and I can pick up all the channels...I was able to pick up all of the channels except for one with just the antenna...I had to add it's little inline amplifier to get every single channel available to me. I'm not sure I'd believe the 45 miles number on the box but if you are relatively near your tower and need an indoor antenna it's not a bad buy if you want something unobtrusive in the room (mine is standing on my corner stand behind the new LCD TV)...another one to look at might be

http://www.antennasdirect.com/SR8_indoor_yagi.html

but it's currently out of stock there.

I'll be connecting to a Fusion5HDLite for the pc tonight and I'll see if I can get some signal strength readings.

Naylia

01-04-06, 09:18 AM

Double post...deleted

DaveK913

01-04-06, 04:15 PM

Okay, I've been doing some reading here for awhile, and I guess it's time for me to jump in. I've posted in a couple of places, but this looks to be a very well visited topic here.

A couple of years ago, we had a Sylvania SRZ3000 OTA receiver hooked up to one of the RS double bowtie antennas. We never received a particularly strong signal, and had plenty of signal drop. Needed a few extra dollars and sold it, deciding to wait awhile until technology improved and became more prevalent.

So, we're about to delve back in. We have DirecTV and are going to pick up the H20 receiver(Or the DVR if finances allow), and are looking into getting our OTA HD channels since we're fairly close to our towers. Remembering my previous experience, I decided to look into what's best to use. I haven't dealt with an antenna since the 70's, so I'm kind of out of touch.

We're within 5 miles of all our towers, and they're all within 14 degrees of each other to the southwest(231.65-244.71). The terrain is fairly level about a mile out from our house, then slopes upward ~25 feet over the next mile or so, where there is a patch of trees in the direction of the tower. Over the next 2 miles, the terrain rises about 100 feet or so, then fluctuates slightly but stays fairly steady. The towers are all around 130 feet above our elevation.

Antenna path/topography (http://home.comcast.net/~dklink913/antennainfo.jpg)

The frequencies for our stations currently are 30, 35, 42, and 58. The stations broadcast between 220 and 560 kW. The towers are all over 900 feet tall, and easily visible from our elevation, but not from our specific vantage point. For more specific information, our zip is 46544.

Our backyard and surrounding area is full of trees. We have 4 over 30 feet tall in our back yard pretty much right in the path from the house to the towers. We have a split level house with aluminum siding. There's a mast on the higher, southern section of the house, total height of around 21 feet. It's east of a 30 foot maple tree that is around 15 feet from the back of the house. The spread of this tree comes right up to the house around 10 feet from the mast. Our television is around 40 feet to the north from this mast.

Immediate area (http://home.comcast.net/~dklink913/antennadirection.jpg)

This picture is taken from the top of the mast in the direction of the towers.

Mast view at ~238 degrees (http://home.comcast.net/~dklink913/mastviewtrees.jpg)

The 30' foot tree is 15' from the house, the 35' is 20 feet, the 50' around 60 feet, the 70' on the right about 60 feet, and the 70' to the left is in a neighbor's yard behind us and to the south also in the general path around 80-90 feet away. The small horizontal red line represents the mast. The lines don't represent the direction completely accurately, since they're done from a frontal perspective rather than from above.

Frontal property perspective (http://home.comcast.net/~dklink913/antennahousetrees.jpg)

I was hoping to use either an indoor or attic mount antenna, ideally placing the attic mount over the living room, which is around 3.5-4 feet lower than the upper level. Our roof has a 4/12 pitch and from the ones I've read about, either the AntennasDirect DB2 or DB4 would fit in that space. From the ridge beam to the top of the ceiling joists is around 48 inches, so there's not a lot of room for rotation. We would prefer not having to use a roof mount, and with the one tree so close to the roof it would be mounted on, didn't know if it would be any more feasible than the attic mount if an indoor antenna didn't pan out.

Tower Guy

01-04-06, 05:44 PM

I like the pic and possibility...but i was thinking of just 2 antennas...one for all but channel 42 and 67or64....I'm thinking I can line up 42 and either 64 or 67 but 64 and 67 wont come in well at the same time. So if i can just aim one of them along with 42, it would work out pretty good

i guess i have the option in your picture but that's a bit more than i wanted to pay :)

Try this;

One all channel antenna, one antenna for 42/6X. Get jointennas for 42 and 6X. Use a two way splitter on the 42/6X antenna and use that to feed the two jointennas. As long as the 42/6X signals are strong enough, you'll have what you need with two antennas, two jointennas, and a two way splitter.

sregener

01-04-06, 05:59 PM

We have a split level house with aluminum siding.

I was hoping to use either an indoor or attic mount antenna...

You could try something indoors, but your siding is acting like a great big reflector - almost nothing is going to get through it. Unless you can shoot through shingles instead of siding, you'll just get frustrated in there.

That said, a DB4 would be excellent on your roof, and it wouldn't be worthless to try it in the attic first (maybe you'll be lucky...) But plan on the rooftop.

Skip amplifiers - you're too close to the towers.

DaveK913

01-04-06, 06:18 PM

You could try something indoors, but your siding is acting like a great big reflector - almost nothing is going to get through it. Unless you can shoot through shingles instead of siding, you'll just get frustrated in there.

That said, a DB4 would be excellent on your roof, and it wouldn't be worthless to try it in the attic first (maybe you'll be lucky...) But plan on the rooftop.

Skip amplifiers - you're too close to the towers.

From what I'd read, I kind of figured that but was hoping how close we were would help.

Would how close the tree at the back of the house is to the mast have a terribly adverse effect considering the tree rises about 10 feet or so above the height of the mast, and would it help to install a new mast closer to the front of the house about 10 feet further from that tree? I have no qualms about doing that and could always use a reciprocating saw to cut the legs off the old one if my wife says it looks like the house is growing shoots. :)

Thank you for your response!

newsposter

01-04-06, 09:07 PM

Try this;

One all channel antenna, one antenna for 42/6X. Get jointennas for 42 and 6X. Use a two way splitter on the 42/6X antenna and use that to feed the two jointennas. As long as the 42/6X signals are strong enough, you'll have what you need with two antennas, two jointennas, and a two way splitter.

Thanks for all the options. I love having them available to me because once i get going, i act fast!

and here's a general comment to all:

inches MATTER! I had a few minutes today to adjust the antenna. But first took the amp from between the 75 and 50 ft runs and put it right at the antenna instead. Virtually no difference. BUT, I pushed the antenna up 6 more inches until it was literally touching the inside of the roof. I got a 5-8 boost on the signal for channel 64 and 67 here (but lets see if it's that good in a day or so). 42 is still a no show and 54 is still only 60 signal, but....since I got such improvement on the 60s channels, I feel that i really do have the chance to get good signals all around on the roof. Just gotta find someone to do it.

TVSaurus

01-04-06, 10:08 PM

I have a crazy thought, can I put two signals into my receiver (HDTV PC card) by using a splitter before they enter. So I could buy say the 4228, point it in one direction (28 degrees) and use my indoor antenna to pick up the stations (85 degrees) from the other direction which it does fine? Maybe this is crazy thinking but worth asking I guess. Maybe the tuner can only tune from one antenna at a time or something.

Is this possible? I'd like to do the same exact thing so that I can receive about 6 more HD signals from the opposite direction.

TheRatPatrol

01-04-06, 11:27 PM

Just hooked it up last night...I am in the Boston area roughly 6 miles from towers spaced between 217 deg and 225 deg and I can pick up all the channels...I was able to pick up all of the channels except for one with just the antenna...I had to add it's little inline amplifier to get every single channel available to me. I'm not sure I'd believe the 45 miles number on the box but if you are relatively near your tower and need an indoor antenna it's not a bad buy if you want something unobtrusive in the room (mine is standing on my corner stand behind the new LCD TV)...another one to look at might be

http://www.antennasdirect.com/SR8_indoor_yagi.html

but it's currently out of stock there. The DB2 is also a potential indoor antenna but it really needs to be attic mounted

I'll be connecting to a Fusion5HDLite for the pc tonight and I'll see if I can get some signal strength readings.

What kind of building are you in, what floor are you on, and do you have other buildings between you and the towers?

I'm trying to help my friend get an HD signal in his 3 story condo. He occupys all 3 stories. His HDTV is on the 2nd floor.

Thanks.

rothgar

01-05-06, 12:09 AM

I did not realize this thread was so long. I read the first 10 pages then skipped through. Great information so far but I have a coupse questions also.

I would like to know about combining antennas to get better signal. 2 antenna's (roof antenna and indoor powered antenna) into 1 hd tuner box. I figure it wouldn't hurt to try but someone might no the specifics of why it would or would not work.

here is my next question. I am in southern California (LA area) and I can see the antenna's that broadcast almost every hd station I would ever need. I am in a 1 story apartment with only trees separating me from the towers. I am 6.4 miles away from the towers according to antennaweb and they suggested a indoor non powered antenna to pull in every channel. I have tried rabit ears, roof antenna (my neighbors), and a powered antenna. I can easily get channels 2,5,7,9 but the channel I really want is 11. All three antenna's have about 50% signal strength no matter what i do (pre amp, line amplifyer, etc) Is there any way (or a better antenna I can try) that can specifically pull in certain channels? the current antenna I am using is the Terk5 but it still wont get more than 50% signal for anything. Please help me out I really would like the rest of the channels. Thank you.