[by1234]



Quote:
Originally posted by imott
Have you taken a look at the topo for your address at Terraserver? You are on the East side of San Pablo Ridge I think Sutro would be tough unless you are near the top. El Sobrante is quite hilly; are you on top of one or down in one of the valleys? Can you see Sutro Tower from your roof? If not, I might suggest you try for some of the channels to your East (See Dswallow's post a few posts back). Do you have a compass? Knowing where you are in relation to the obstructions around you are key to making this work. I wouldn't rule out an indoor antenna; however, I'd be suprised if you could get anything without going outdoors and up! I just had to put a 30' pole in the ground to pickup Sutro from Cupertino. Now that I have...I couldn't be happier!!!

I tried a RS 15-1880 last night and was able to get 2 ABC channels (dropping in and out intermittently). I am about half way up the hill. I will try the Silver Sensor next since I don't want to push my luck trying to sneak a huge outdoor eyesore past my wife.

....at least not yet.


I don't think east is an option for me since I am on the west side of the hill in the middle. The hill is directly blocking anything from the east.

 

[imott]



Quote:
Originally posted by by1234
I tried a RS 15-1880 last night and was able to get 2 ABC channels (dropping in and out intermittently). I am about half way up the hill. I will try the Silver Sensor next since I don't want to push my luck trying to sneak a huge outdoor eyesore past my wife.

....at least not yet.


I don't think east is an option for me since I am on the west side of the hill in the middle. The hill is directly blocking anything from the east.

Check this one out...Not big at all! 36" tall x 20"wide x 4" deep. Channel Master 4221 About $45.

 

[rdwalt]

Acutally you can pick up a 4221(3021) from your local ACE Hardware for ~ $25

 

[j-bo]

Slapshot et al,


Thanks for the input on the hughes STB. I rescanned a bunch of times. Checked the signal on some local digital stations which was at 100%, but the scan wouldn't pick it up!


Goin shoppin for an OTA receiver, rotator, and a CH7777.


Returning the r/shack preamp/amp.


Wife thinks I'm bozo.

 

[Platup]

I currently am using a Terk HDTVi (silver sensor knockoff with VHF rabbit ears). I get almost every channel. One station I can't get the 3rd subchannel (I get 8.1 and 8.2, but can't get 8.3). The other 4.1 won't come in at all, but I can get another station in the same direction that is further away.

Will adding any kind of amplifier help? If so, any suggestions on what kind and where to get it?

 

[sregener]



Quote:
Originally posted by Platup
One station I can't get the 3rd subchannel (I get 8.1 and 8.2, but can't get 8.3). The other 4.1 won't come in at all, but I can get another station in the same direction that is further away.

Amplifiers and indoor antennas almost never mix well.


No amplifier or antenna upgrade is going to get you 8.3. If you're getting a solid picture on 8.1 or 8.2, the problem is either that your receiver isn't properly decoding the signal (possible,) or more likely that the station doesn't intend for viewers to use 8.3 and it's there as a placeholder. The entire 19Mbps ATSC stream has to be decoded to figure out the information in 8.1 or 8.2, which means that the problem with 8.3 isn't signal strength or signal quality.

 

[Platup]

Thanks Sregener that helps.


It's most likely the receiver. I'm currently using a Fusion 3 in a HTPC. If I use the same antenna with my dish reciver I get everything including 8.3 and 4.1. With the fusion 8.3 has come in before, but goes in and out almost like a week signal, but 8.1 will be fine. In fact, sometimes I get 8.2 on 8.3 and vice versa.

 

[greenknight]

Noticed a setup a few blocks away where the ota antenna is mounted above the dish and appears to be delta wing shaped unit that is very thin.

Any idea what this is? The dish is a 3-lnb D* unit. Thanks

 

[CHAS ZOSS]

Greenknight, I beleive it is a Channelmaster stealth ant.

 

[imott]



Quote:
Originally posted by greenknight
Noticed a setup a few blocks away where the ota antenna is mounted above the dish and appears to be delta wing shaped unit that is very thin.

Any idea what this is? The dish is a 3-lnb D* unit. Thanks

Channel Master Stealth

 

[ericdwong]

I'm going to apologize in advance for posting this but I hope the mods do not delete it. This seems to be one of the best resources of knowledge on the net regarding antennas, so I'm going to ask this here, regarding antennas for FM for the car.


...my car came OEM with diversity reception, the only problem now is I

put in an aftermarket radio which uses only one antenna. The car uses 2

in the glass style antennas, one in the front of the car, one in the

rear of the car. I tried to use just one of the antennas with the

aftermarket radio and it seems as though the front antennas is good for

the upper 1/2 the FM band and the rear one is good for the lower 1/2.

If I plug both in at the same time, the reception is very "multipathy",

probably because both antennas are used at the same time effectively

picking up alot of garbage and cancellation. Overall, the reception is

very poor.


I was thinking if there is an externalbrain that could be used as the

diversity switcher. Is there such a thing?


Unfortunately I think this may have to be done in conjunction with the

radio since it is probably specific to which frequency the radio is

tuned in on but I'd though I'd ask anyway.


I tried one "solution" is one of these small amplified antennas that

tape onto the windshield. Unfortunately, the unit was alot smaller then

I had expected, it is probably 1/8 wavelength. It is

amplified but it works worse then the OEM antennas.



PS I'm looking into other antenna options as well. the car is a plastic

body on frame design (chevy corvette), it does not really have a large

"ground plane" so to speak, other then the frame of the car itself. I

really dont want to put any huge antennas on the outside of the car

either, although the convertible models did have a powered "whip" style

antennas I'm not too inclined to punch a hole in my car to put it on.



I'm thinking about boat antennas since many boats are of similar

composite body/metal frame designs.



The rear bumper of the car has a very large area behind it, I think I

may be able to fit even a 1/2 wavelength antenna back there, but

horizontally. Can anybody recommend either an antenna thats premade or

one that I can fabricate that will work well for my application?


Or, if someone can point me to the right direction on a FM enthusiast chat board?

 

[toddr007]



Quote:
Originally posted by sregener
You just did. Weak signals show up on analog as snow. Multipath shows up as ghosting. (Some people get both.) If you're getting snow but not ghosting, a weak signal is your problem, not multipath.


The solution for a weak signal is either a larger antenna (like the 4228) or a preamplifier. I'd go with the preamp, personally. Get one from Channel Master or Winegard that has less than 20db of gain. The top gain models might overload. There's no guarantee that this will work, so keep your receipts.

I just wanted to update what I've done to get things working for me. Since I didn't have time to go buy a decent amplifier (before the Superbowl that is), I decided to at least do what I could to minimize losses between the antenna and my TV. I mentioned in my original post that I was using the old cable that was up on the roof since I bought my house (over 12 years ago), and that I was going through a splitter since that was where the main cable (RG59?) joined the original antenna.


So I bought 50' of new RG6 and ran that straight from my antenna to the TV - and ...(cue drum roll please) the signal / noise ratio on almost every channel was improved by 6 to 10 dB, and the signal strength was up by 20% or so. I now can pick up all of the digital channels fine including the elusive channel 50 (KSTP) 5.1, and some of the weaker signals that hadn't been detected by previous scans (KTCI channel 17.1-17.5 on broadcasting on 16 with 50kW of ERP). Also the reception on high band VHF isn't bad at all. Only the low band VHF is a little bit snowy - but it's better than I would have expected with a UHF antenna (CM 4221). Besides - I wasn't really planning on watching much analog TV with this set anyway - at least with this antenna setup. So at least for me, paying attention to the cable and connections helped a lot.


Of course, this brings up a question. It's hard to tell what gained me the most - the elimination of the splitter or the new cable, but I have to assume at this point that the dielectric in the old coax has deteriorated over time. Does anyone have an estimate on how much or how fast that happens - or rather more simply - what is the life expectancy of coax? Is there a preferred brand or type that holds up better to exposure outdoors?


Thanks to this forum and especially thanks to sregener for your assistance getting me a little way up the learning curve and helping me understand the nature of my problems.


Todd

 

[sregener]



Quote:
Originally posted by toddr007
So I bought 50' of new RG6 and ran that straight from my antenna to the TV - and ...(cue drum roll please) the signal / noise ratio on almost every channel was improved by 6 to 10 dB, and the signal strength was up by 20% or so.


Of course, this brings up a question. It's hard to tell what gained me the most - the elimination of the splitter or the new cable, but I have to assume at this point that the dielectric in the old coax has deteriorated over time. Does anyone have an estimate on how much or how fast that happens - or rather more simply - what is the life expectancy of coax? Is there a preferred brand or type that holds up better to exposure outdoors?

Your splitter is capable of introducing a 3.5-4db loss, depending on its quality. 3db is a gain/loss of half the absolute signal strength.


Bad connectors can cause all sorts of problems. If you waterproof them, there's no reason for the cables to go bad. The middle of your RG59 was probably fine, but the connectors at the end rusted some and deteriorated over time. Really, it doesn't matter what kind of coax you use - the ends are the only possible point of breakdown due to weather. (You can, of course, run over the cable with your lawn mower or clip it with hedge trimmers, which would cause some loss in the middle of the cable...) Weather boots help.


Your average antenna has a lifespan of about 10 years, after which it starts breaking down itself because of rust. The connectors of the twin-lead alone can go bad. As a general rule, when you replace the antenna, you should replace all the outside connections as well.


Glad to hear you had success with such a simple solution.

 

[cjhrph]

Registered: Mar 2004

Location: Central NY (Utica/Syracuse)

Posts: 10

Attention Antenna Guru's


I live in ZIP 13323 approx 30-40 miles from the towers. Its hilly terrain here and im not at one of the highest elevations in the area. I have been messing with the DTV signals for the last year and have tried the following equipment/setup.


Zenith HDV420

Samsung 351

Samsung 165


Channel Master 4248, 4228

Winegard PR-9032


Channel Master 7777 pre-amp


Rooftop install with rotor ~ 35 ft above ground.


It appears that for my location the Yagi's work better than the bowtie, presumably due to multipath. I have not been sucessful with either of the Samsung's, they just cant lock and hold the signals.


The 420 with the Winegard has been pretty good on most channels. However, I still suffer from random dropouts and pixellation. I recently picked up an LG4200A receiver and its pretty good except it completely rejects one of the stations that I used to get with the 420.


I am considering a different antenna, perhaps the DAT-75, JBX-21, or XG91. I was hoping that one of these designs may just be that much better than the Winegard to allow for better success. I really cant get any more height without erecting a tower.


Could someone that has used one of these other antennas tell me if they think this would be a worthwhile upgrade. And if so, where to purchase the european antennas. I know where to get the XG91.


Thank You

 

[sregener]



Quote:
Originally posted by cjhrph
Could someone that has used one of these other antennas tell me if they think this would be a worthwhile upgrade. And if so, where to purchase the european antennas. I know where to get the XG91.

Last question first:
http://cpc.farnell.com/jsp/home/homepage.jsp


It's hard to say if it would be worthwhile or not. I assume you've read my 91XG review ( http://www.geocities.com/figbert/ant...irect91xg.html ) and so you've seen that I still haven't gotten completely reliable long-distance reception. Sadly, once you're below the radio horizon, more antenna makes a difference, but it's a subtle one.


The PR-9032 is an excellent antenna, over 114" long. The 91XG is 21" shorter. Length matters, but only on higher channel numbers. Once you get below channel 32, you're really using a corner reflector rather than a yagi. (Exception: some yaigs are tuned for channels lower than 69, but no "regular" UHF antenna is.) And looking at the corner reflector for the 9032, I think the 91XG's is better.


I think the difference is probably going to end up being subtle. You'll still get breakups, but they won't be quite so common, and they won't be as disturbing. Whether it's worth it to you to spend that kind of money for a minimal improvement is up to you.


More likely, once the next chipsets come on the market, like the one just announced at CEA by Samsung that is supposed to be "the bomb" with weak signals, an upgraded receiver will solve the issues. There really isn't too much difference between the 3rd (420HDV) and 4th (LG 4200A) receivers for weak signals. Their primary benefits were for multipath.


The best thing you could do is add some height to your installation. I know that means a tower, but that gives you the best shot at success. A doubling of antenna height is worth about 20db, which is more gain than the biggest, baddest antenna in the universe compared to a UHF loop.


All of this assumes, of course, that your cabling is quality (RG-6 or better, shielded) and all of your connectors are good (have you tried replacing the balun?) and you have no splits in your line (splitters are bad.)


Another guy just last week reported replacing the balun on his PR-9032 and all his reception problems went away...

 

[cpcat]



Quote:
Originally posted by cjhrph
Registered: Mar 2004

Location: Central NY (Utica/Syracuse)

Posts: 10

Attention Antenna Guru's


I live in ZIP 13323 approx 30-40 miles from the towers. Its hilly terrain here and im not at one of the highest elevations in the area. I have been messing with the DTV signals for the last year and have tried the following equipment/setup.


Zenith HDV420

Samsung 351

Samsung 165


Channel Master 4248, 4228

Winegard PR-9032


Channel Master 7777 pre-amp


Rooftop install with rotor ~ 35 ft above ground.


It appears that for my location the Yagi's work better than the bowtie, presumably due to multipath. I have not been sucessful with either of the Samsung's, they just cant lock and hold the signals.


The 420 with the Winegard has been pretty good on most channels. However, I still suffer from random dropouts and pixellation. I recently picked up an LG4200A receiver and its pretty good except it completely rejects one of the stations that I used to get with the 420.


I am considering a different antenna, perhaps the DAT-75, JBX-21, or XG91. I was hoping that one of these designs may just be that much better than the Winegard to allow for better success. I really cant get any more height without erecting a tower.


Could someone that has used one of these other antennas tell me if they think this would be a worthwhile upgrade. And if so, where to purchase the european antennas. I know where to get the XG91.


Thank You

In my experience, the DAT75 would provide you with a small but significant improvement pretty much over the entire UHF band. Whether it would be enough, I don't know. The XG91 seems to be by all indications very comparable to the DAT75 but I've never had one myself.


Have you tried different heights of the antenna within the limits of your installation? Sometimes, lower is better (in my case it is). Assuming you have already, your options would be staying with a single antenna and upgrading vs. stacking. Horizontally stacked PR9032's I can tell you will be better than a single DAT75 but not as good as stacked 75's. Stacking horizontally will not only increase gain but narrow beamwidth which helps with multipath and co-channel interference.


If you decide to stack and need help, PM me and I'll be glad to help all I can. I've attached a pic of my stack when I had the PR9032's up.

 

[cjhrph]

The balun.. Ill bet mines crap. And it may have been compromised with humidity/water over the winter. Ill try replacing it with a quality balun and re cutting the connections up there.


Who knows what and where the best balun for the 9032 can be purchased ?


If that doesn't work I may have to try two of them when the weather warms up. Anothher 9032 can be had for not too much money. (Ill have to contact you cpcat).

 

[cpcat]



Quote:
Originally posted by cjhrph


Who knows what and where the best balun for the 9032 can be purchased ?

RS has one: http://www.radioshack.com/product.as...t%5Fid=15-1140


Also from Channelmaster: http://www.starkelectronic.com/cmjoiner.htm

 

[ADevantier]



Quote:
Originally posted by cjhrph
Registered: Mar 2004

Location: Central NY (Utica/Syracuse)

Posts: 10

Attention Antenna Guru's


I live in ZIP 13323 approx 30-40 miles from the towers. Its hilly terrain here and im not at one of the highest elevations in the area. I have been messing with the DTV signals for the last year and have tried the following equipment/setup.


Zenith HDV420

Samsung 351

Samsung 165


Channel Master 4248, 4228

Winegard PR-9032


Channel Master 7777 pre-amp


Rooftop install with rotor ~ 35 ft above ground.


It appears that for my location the Yagi's work better than the bowtie, presumably due to multipath. I have not been sucessful with either of the Samsung's, they just cant lock and hold the signals.


The 420 with the Winegard has been pretty good on most channels. However, I still suffer from random dropouts and pixellation. I recently picked up an LG4200A receiver and its pretty good except it completely rejects one of the stations that I used to get with the 420.


I am considering a different antenna, perhaps the DAT-75, JBX-21, or XG91. I was hoping that one of these designs may just be that much better than the Winegard to allow for better success. I really cant get any more height without erecting a tower.


Could someone that has used one of these other antennas tell me if they think this would be a worthwhile upgrade. And if so, where to purchase the european antennas. I know where to get the XG91.


Thank You

Have you tried moving the current antenna to different location the roof? The difference in mounting location can be a much bigger difference than the antenna themselves. Check out HDTV primer for some notes on "hot spots" and "cold spots".


allan

 

[cjhrph]

Not yet. Its a bit snowy up there right now. The tripod is permanently mounted to the roof and I would have to pull it. It current location is the only one on the roof where you could see the horizon in the direction of the transmitters. Once the snow melts Ill give it a try just for the hell of it.


Someone other than RadioShack must make a really good low-loss balun. I already have one of the channelmasters.