The Official AVS Antenna Topic! [Text View] - Page 3

rwantennasat

11-04-04, 10:27 PM

Originally posted by cpcat
rwantennasat,

I've done extensive comparison b/w the Winegard PR9032 and the Televes DAT 75 and I'll have to disagree with you here. The 9032 is a good antenna especially for the price but the Televes beats it consistently up and down the uhf spectrum in long distance reception.I HAVE TESTED THE TELVES ANTENNAS AND I CANNOT SEE WHERE THEY ARE COMMING UP WITH THEY'RE ADVERTISED GAIN SPECS. I HAVE COMPARED THE LARGEST TELVES AGAINST THE PR-9032 WINEGARD AND HAVE SEEN VERY SIMILAR RESULTS BY THE EYE. I ALSO HOOKED BOTH UP TO MY DIGITAL FSM AND SEEN SIMILAR GAIN FACTORS. I CANNOT JUSTIFY SPENDING THE $$ THAT THESE SO CALLED SUPERIOR DESINGNERS OF YAGIS ARE ASKING TO GET THE SAME RESULTS. IF 1 DB GAIN OF DIFFERENCE IS WHAT WERE TALKING ABOUT IT WOULD BE BETTER TO GET A GOOD PREAMP.

I'll be interested to see your proposed new parabolic antennas.

One criticism of the parabolics is they're prone to multipath which is a bane to digital reception. The relatively low front to back ratio can also be problematic but improved by screening the dish.IM NOT SURE WHERE YOUR GETTING YOUR F to b RATIOS ON PARABOLICS? I HAVE ALL THE SPEC SHEETS AND HAVE FOUND THE PARABOLICS TO HAVE VERY HIGH FRONT TO BACK RATIOS?? THIS IS WITHOUT SCREENING. I USE A CHANNEL MASTER 4251 7 FOOTER AT 72 FT AND HAVE NEVER EXPERIENCED ANY MULTIPATHING. I HAVE 3 DTV'S WITHIN 7 MILES AND NUMEROUS OTHERS ON A REGULAR OCCURENCE OUT TO 75 MILES. IM USING A ZENITH HDV-420 STB. IM IN WESTERN NEW YORK NEAR BUFFALO AND CAN SEE ROCHESTER AND TORONTO DTVS THAT ARE RUNNING UNDER 1000 WATTS OUTPUT. The 5th generation chip due out soon is supposed to improve reception in multipath prone areas so maybe the dish designs will become more attractive. Of course, wind load and weight are major considerations as well.I AGREE ON WINDLOADING THATS WHY I RECCOMEND ONLY A FIVE FOOT MODEL IN REGULAR SITUATIONS AND 7 FT MODELS BEING EXCLUSIVE TO THEY'RE OWN TRIPOD OR TOWER.

calvinb

11-05-04, 09:27 AM

Okay I have decided that I need a pre-amp in order to boost the signal I am getting off my CM 4228. One of my local DT stations is about 40 miles away and my HD picture from it is less than ideal. Currently my antenna is in the attic with a 100" run of RG6 into the back of the HD STB (Samsung 360). My question is: where do I put the pre-amp? I have no power outlet in the attic next to my antenna. Can I put it next to the HD STB 100' away from the antenna? Or am I not doing myself any favors? Currently the signal strength on the station in question is about 45% but it fluctuates. Right now my first choice for pre-amp is the CM 7777. Any help is appreciated. Thanks in advance.

mws6468

11-05-04, 09:45 AM

Originally posted by calvinb
Okay I have decided that I need a pre-amp in order to boost the signal I am getting off my CM 4228. One of my local DT stations is about 40 miles away and my HD picture from it is less than ideal. Currently my antenna is in the attic with a 100" run of RG6 into the back of the HD STB (Samsung 360). My question is: where do I put the pre-amp? I have no power outlet in the attic next to my antenna. Can I put it next to the HD STB 100' away from the antenna? Or am I not doing myself any favors? Currently the signal strength on the station in question is about 45% but it fluctuates. Right now my first choice for pre-amp is the CM 7777. Any help is appreciated. Thanks in advance.

You install the preamp at the antenna and the power supply close to the TV, no need for an outlet in the attic. Make sure if you are using any splitters you put them after the power supply.

sregener

11-05-04, 10:44 AM

Originally posted by rwantennasat
I HAVE TESTED THE TELVES ANTENNAS AND I CANNOT SEE WHERE THEY ARE COMMING UP WITH THEY'RE ADVERTISED GAIN SPECS. I HAVE COMPARED THE LARGEST TELVES AGAINST THE PR-9032 WINEGARD AND HAVE SEEN VERY SIMILAR RESULTS BY THE EYE. I ALSO HOOKED BOTH UP TO MY DIGITAL FSM AND SEEN SIMILAR GAIN FACTORS. I CANNOT JUSTIFY SPENDING THE $$ THAT THESE SO CALLED SUPERIOR DESINGNERS OF YAGIS ARE ASKING TO GET THE SAME RESULTS. IF 1 DB GAIN OF DIFFERENCE IS WHAT WERE TALKING ABOUT IT WOULD BE BETTER TO GET A GOOD PREAMP.

If you already have a good preamplifier, you know that a preamplifier can't fix what isn't there. IOW, if you have 4db of gain and a 28db preamplifier, you will have a worse signal for digital reception than if you had 16db of gain and a 10db preamplifier. Preamps fix line loss, nothing more. They can't create signal where it isn't.

Where that 1db really makes a difference is right on the margin between a good and a bad signal. If you have stations that you can get with one antenna and can't with another in the same spot, then you can claim one antenna is better than the other *for that particular frequency over that particular terrain under those particular weather conditions.* There's no doubt that the DAT-75 and PR-9032 are close. But they're not equivalent and there are times when I would expect one to outdo the other, simply because their designs are different.

I'm not saying that a parabolic antenna can't do a good job. Maybe they can. The only one I've seen run through tests is GlennL's tests in southern California where the CM 7' parabolic did horribly compared to yagi-style antennas for digital reception with multipath. (http://www.atechfabrication.com/tests/04-24-01_test_results.htm)

RobWis

11-06-04, 12:14 AM

I live in a region where a second dish is required to receive local stations. He said if I want to be able to receive the locals from the additional satellite and from an off-air antenna simultaneously that I would need an "HD off-air antenna." He said the Terk clip on antenna I have up there now doesn't have enough strength to carry the signal when wired in conjunction with the second dish.

Is this correct? If so which antenna will I need...the Terk TV55 maybe??

Thanks guys

greywolf

11-06-04, 12:48 AM

Avoid all Terk OTA antennas. They are overpriced and underperforming except for the 30 series numbers. They are merely overpriced. The best antennas look like antennas. Look at Channel Master, Winegard, Antennas Direct, even Radio Shack. The Terk antennas that work decently are made by Winegard and upped 50% in price. Check out http://antennaweb.org/aw/welcome.aspx for help in choosing an antenna.

dkyork

11-06-04, 10:36 AM

Originally posted by greywolf
Avoid all Terk OTA antennas. They are overpriced and underperforming except for the 30 series numbers. They are merely overpriced. The best antennas look like antennas. Look at Channel Master, Winegard, Antennas Direct, even Radio Shack. The Terk antennas that work decently are made by Winegard and upped 50% in price. Check out http://antennaweb.org/aw/welcome.aspx for help in choosing an antenna.

Is it safe to mount a 4228 to the roof? The D* tech came by and said that the Winegard gs2200 was not going to cut it and instead of charging me, he sid he would say that I canceled. He suggest a 40 foot mast and mounting the 4228 on it, but would it be easier to mount the 4228 to the hardware already on the roof from the gs-2200? It's already about 36 foot up.

thanks,

Dale

greywolf

11-06-04, 12:35 PM

The 4228 is a very good UHF antenna.

lman12

11-06-04, 01:29 PM

I live in Central New Jersey, about equal distance from NYC and Philadelphia (65 miles each way). I would like to pick up the digital Hi-Def channels from each city. In addition, I would be interested in picking up the higher band VHF channels. What would be the best "Deep Fringe" antenna, CM 4228 or CM 3020, for me?

If someone in this forum can think of a better antenna than the two listed above, let me know.

I enjoy this forum.

lman12

beboram

11-06-04, 04:57 PM

My choices are

Wineguard HD -9065 or Channelmaster 4221.

1. The installer says they are both equivalent for reception - are they?

If Yes which one would visibly stick out less mounted on the roof top?

2. Which one is least affected by snow and ice build-up?

3. Least affected by wind? - My 'hood tends to get quite windy during the winters.

BTW I am about 30 miles NW of Washington DC.

You can see the antennas here:

http://fairfaxantenna.com/ffx921/TV_Antennas.html

MAX HD

11-06-04, 09:01 PM

Originally posted by lman12
I live in Central New Jersey, about equal distance from NYC and Philadelphia (65 miles each way). I would like to pick up the digital Hi-Def channels from each city. In addition, I would be interested in picking up the higher band VHF channels. What would be the best "Deep Fringe" antenna, CM 4228 or CM 3020, for me?

If someone in this forum can think of a better antenna than the two listed above, let me know.

I enjoy this forum.

lman12

The best combination for the distance involved would be seperate UHF/VHF antennas.
The CM4228 is a decent UHF antenna,but some others that come to mind would likely work better for the Philly DT channels above Ch60,such as the XG91 available domestically from Antennasdirect,and some models from the UK ( www.cpc.co.uk ) such as the Triax Unix100,Funke DC4591,and the Televes DAT-75 Wideband models.

Good upper VHF(high-band) antennas would be the Antennacraft or Winegard 10 element models available from Starkelectronic or Warrenelectronics dot coms.Or,if you want the best high-band antenna available on the planet,I have some coming in the near future.

http://community-2.webtv.net/GregBarker/UltraHighGain/

A CM 9521 rotor on a moderately sturdy mast will easily turn the above mentioned UHF/VHF antennas.The best preamp I've used for seperates is the CM 7777.

f13dfx

11-06-04, 10:04 PM

I live in Vancouver, BC, Canada which is 116 miles (line of sight) from Seattle, WA. Here are the channels broadcasting in HDTV that I want to pickup:

Seattle, WA - ABC (4) - CBS (7) - FOX (13) - NBC (5) - PBS (9) - upn (11) - wb (22)

Can someone recommend the best antenna or antenna combination for my location? Or am I a little too far away?

Thanks in advance!

greywolf

11-06-04, 11:15 PM

The curvature of the earth limits line of sight to about 60mi. You would need a heck of a tower.

f13dfx

11-07-04, 03:29 PM

Originally posted by greywolf
The curvature of the earth limits line of sight to about 60mi. You would need a heck of a tower.

Okay, I live in a two-storey house, so the antenna would be approximately 30 feet high. Only thing is that Richmond, BC is at sea level.

I do not know much about how VHF & UHF signals transmit, but do they mainly just go by "line of sight"?

I guess Bell Express Satellite would be the best for HDTV for me :(
Damn, that would cost me $50 Cdn./month. Not worth it right now for 14 channels (mostly USA networks, TSN & Rogers SportsNet).

greywolf

11-07-04, 04:38 PM

VHF will bend a little but UHF is very LoS. 30 ft won't nearly do it. You would pretty much need both transmitter and receiver to be on mountaintops plus a lot of luck..

firemantom26

11-07-04, 10:50 PM

I just bought the Samsung 26" HDTV (TX-P2675WHD)
• Built-in HD tuner • Widescreen
• A/V versatility

What is the best indoor antenna with a pre amp to buy?

Ssecca

11-08-04, 12:23 PM

Can Regular cable be used to get HD programing with a HD dtv sir-360 box..I have had regular cable here since I moved in and was wondering if it was worth running that over there to my set up??Or is off air the only way???TIA..:D

arxaw

11-08-04, 12:38 PM

Originally posted by firemantom26
...What is the best indoor antenna with a pre amp to buy? "Best" varies, depending on location and stations in your area (VHF/UHF or both). See the local thread for your particular location here (http://www.avsforum.com/avs-vb/showthread.php?postid=4441186#post4441186).

arxaw

11-08-04, 12:42 PM

Originally posted by Ssecca
Can Regular cable be used to get HD programing with a HD dtv sir-360 box..The SIR-TS360 will only receive DirecTV, OTA digital/analog and analog-only cable channels.

GB Randy

11-08-04, 02:49 PM

I live 5.5 miles from the "antenna farm" in Green Bay, WI.

I installed a Terk 44 sat dish antenna and had marginal results on my TS360 HDTV box. I had drop outs and in some cases no reception.

I installed a Zenith GEMDTV-1 antenna. It is directional and I have it pointing directly at the antennas. Heck I can see them towering 2,000 feet into the air right by my house. I thought I was good to go....

My reception is worse! I do not get one channel at all and two others had drop outs all during the CHI / NYG football game.

What am I missing here? I have the unit mounted on the side of my house next to my dish....do I need to move it away from the side ofthe house? Away from the dish?

I have about 50 feet of cable from the antenna location to the set top box....

Any and all thoughts are welcome.

sregener

11-08-04, 05:38 PM

Originally posted by GB Randy
I installed a Terk 44 sat dish antenna and had marginal results on my TS360 HDTV box. I had drop outs and in some cases no reception.

I installed a Zenith GEMDTV-1 antenna.

Take both these overhyped antennas back to the store, give the clerk a piece of your mind about the junk they are, and pick up a Zenith Silver Sensor. It will outperform both by a mile, costs less, and has given lots of people success.

(Note: It can be hard to receive digital signals when you are in the shadow of the transmitter. The antenna is aimed for the horizon, and if you are far enough below that level, it can be hard to find much, if any, signal. You may have to try aiming in "non-intuitive" directions to pick up a reflection, and hope your receiver can handle multipath. You might want to try aiming any antenna you have *up* so it's pointing at the top of the tower, not the bottom.)

PhilJSmith67

11-08-04, 05:49 PM

GB Randy, at that distance (assuming clear line-of-sight), you should be able to get the DTV stations if all you had for an antenna was a couple feet of the RG6 center conductor exposed!

You might actually have too much signal. Have you tried an RF attenuator on the antenna line?

arxaw

11-08-04, 09:26 PM

Originally posted by GB Randy
I live 5.5 miles from the "antenna farm" .... I can see them towering 2,000 feet into the air right by my house. I thought I was good to go....Try tilting the antenna UP toward the top of the towers. Or at that close of a distance, try a simple indoor loop antenna. As others have said, you may have too much antenna.

rwantennasat

11-08-04, 10:52 PM

[QUOTE]Originally posted by lman12
[B]I live in Central New Jersey, about equal distance from NYC and Philadelphia (65 miles each way). I would like to pick up the digital Hi-Def channels from each city. In addition, I would be interested in picking up the higher band VHF channels. What would be the best "Deep Fringe" antenna, CM 4228 or CM 3020, for me?

If someone in this forum can think of a better antenna than the two listed above, let me know.

I enjoy this forum.

lman12 [/

First of all neither of those antennas are any good for high vhf channels.
if you only want uhf then a 4228 or better yet a winegard 9032. you will also need a good pream because these are quite a distance from you. i reccomend the ap-4800 by winegard. in fact i bought 100 + of these and my shop sells em cheaper than anywhere you can find! Now back to vhf high ch's if you want a really good all around i suggest a winegard pr7052 combo or a hd8200 or channel master 3671 with a preamp. you'll also need a rotor due to various dsirections. i would be glad to design a system for you. drop me an e-mail at:rwantsat@localnet.com
take care Rich

rwantennasat

11-08-04, 11:15 PM

Originally posted by sregener
If you already have a good preamplifier, you know that a preamplifier can't fix what isn't there. IOW, if you have 4db of gain and a 28db preamplifier, you will have a worse signal for digital reception than if you had 16db of gain and a 10db preamplifier. Preamps fix line loss, nothing more.

Im not sure what school you went to regarding signal reception and the proper use of amplifiers that are mast mounted or distribution stlye amplifiers. My teaching and 25 years in business would say that DISTRIBUTION or post amplifiers are for increasing line loss. However, mast mounted Preamplifiers are to increase the incomming signal to increase the amount of S/N ratio to the tuner. The ideal choice is to use the lowest possible noise rated preamps to reduce increasing noise to the receiver.
This is especially true on UHF. I prefer Winegards design when it comes to uhf Preamps due to the fact they use a hemt design transistor which induces very little noise. Anyhow there have been numerous times in our business that a simple yagi or stacked yagi's simply would not provide a proper signal to a headend. After inserting a 20-29 db amplifier the signal was brought up to usable and was able to be distributed to 100-2000 sets in a commercial enviornment! This hold trure for those using a preamp at home.I watchj HDTV stations out to 75 miles with a 7 ft parabolic and a winegard 17 db uhf amp. If that was not there(the preamp) i would not see those channels. I've done it both ways and Preamped is best. A distribution amplifier does nothing more than to keep a steady amount of equal signal to all tv's on the system while also overcomming losses incurred by enourmous lengths of cable/feedline!

They can't create signal where it isn't.

Where that 1db really makes a difference is right on the margin between a good and a bad signal. If you have stations that you can get with one antenna and can't with another in the same spot, then you can claim one antenna is better than the other *for that particular frequency over that particular terrain under those particular weather conditions.* There's no doubt that the DAT-75 and PR-9032 are close. But they're not equivalent and there are times when I would expect one to outdo the other, simply because their designs are different.

I'm not saying that a parabolic antenna can't do a good job. Maybe they can. The only one I've seen run through tests is GlennL's tests in southern California where the CM 7' parabolic did horribly compared to yagi-style antennas for digital reception with multipath. (

For more info on how well parabolics are doing for dtv over air reception you should go to WTFDA.com Its the home page for the worldwide tv/fm dxing assoc. Which i have been a member of for over 20 years. Their are many members using parabolics on uhf and watching dtv and dxing it out over 800 miles!!!! I believe Greg baker is also a member and he has alot of input on this forum (Hi Greg)
http://www.atechfabrication.com/tests/04-24-01_test_results.htm)

cpcat

11-09-04, 07:51 AM

However, mast mounted Preamplifiers are to increase the incomming signal to increase the amount of S/N ratio to the tuner. The ideal choice is to use the lowest possible noise rated preamps to reduce increasing noise to the receiver.

Neither preamps nor distribution amps can "increase signal" or increase signal to noise ratio on an absolute basis. The best possible S/N ratio is right at the output of the antenna. The signal can only get worse from there no matter what you do to it. A perfect preamp would give you a S/N at the tuner that is equal to the S/N at the ouput of the antenna, perfectly compensating for line loss and adding zero noise. Obviously, this doesn't exist in the real world.

The Winegard AP-4800 is generally felt to be equivalent in performance to the CM 777x series. The advantage of one over the other isn't necessarily performance related, but feature related, i.e. if you want separate uhf/vhf 75 ohm inputs, you'll need the CM 7777. If you want a preamp that passes vhf, go with the Winegard.

Nitewatchman

11-09-04, 09:41 AM

While it is true the signal itself won't get any "stronger" than is the case at the antenna, it is possible that a preamp CAN lower the over all noise floor that front end of receiver "sees", therefore, in a practical sense, a good preamp(in the right circumstances) can "raise" the overall S/N ratio. If the preamp is getting overloaded by strong signals+is producing Intermodulation distortion however, it's likely to ADD noise to the system, but usually in a "frequency specific manner, that is probably going to involve quite a few frequencies/channels.

See the sections at following link concerning "UHF receiver system sensitivity"(about 1/2 way down the page)., "Low noise UHF TV preamplifiers", "Suggested list of UHF TV preamplifiers", and "UHF line amplifiers".

http://www.geocities.com/toddemslie/UHF-TV-DX.html

You may find the rest of the info at above link useful as well.

GB Randy

11-09-04, 05:13 PM

[QUOTE]Originally posted by sregener
[B]Take both these overhyped antennas back to the store, give the clerk a piece of your mind about the junk they are, and pick up a Zenith Silver Sensor. It will outperform both by a mile, costs less, and has given lots of people success.

Well, well, well. I am on my fourth antenna, an attenuator, and pre-amp. As some may recall, I live 5.5 miles from the antenna's in Green Bay, WI.
Just for the heck of it I bought the Zenith Silver Sensor at lunch.

My system is in my basement I hooked up the antenna and threw it on the floor (not pointed in any real direction) and turned on the TV. I have a perfect picture on every channel. I TRIED to make it drop a signal...if I pointed it straight at the floor it was struggling with our weakest signal (channel 11 - FOX). Otherwise it got everything! Man I spent a lot of money and time hooking up big antennas.....now I have to take it all down and return it...

Terk 44 = was OK
Terk 55 = Junk
Zenith GEMDTV-1 = Marginal but wrong for my application
Zenith Silver Sensor = Little, teeny tiny, erector set, plasticy thingy was perfect.

I guess size doesn't always matter

An interesting side-bar. I unplugged the outside antenna and just had the transformer hanging on the wall and my signal was unaffected by it.

Read: I was receiving almost all the same channels as I was with the darn thing hooked up....Channel 5 & 11 were the only drop outs....hummmm

cpcat

11-10-04, 07:38 AM

therefore, in a practical sense, a good preamp(in the right circumstances) can "raise" the overall S/N ratio.

Only at the receiver, not at the output of the antenna, agree?

jaq

11-10-04, 08:12 AM

I am thinking of placing one in my attic. I have a two story house with a composite roof and live about 20 miles from most towers. Radio shack has one for about $75 (any other suggestions?). Would a standard mast antenna be any better? Most of the towers are in the same area.

Nitewatchman

11-10-04, 09:46 AM

Originally posted by cpcat
Only at the receiver, not at the output of the antenna, agree?

Yes, I agree. In fact, I believe I said that in first sentence of last post.

greywolf

11-10-04, 09:54 AM

Omnidirectional antennas are generally not a good idea due to acceptance of reflected signals from nearby objects. Attic mounting one is a very bad idea. Signal reflections from the attic surfaces come in out of phase and cause havoc. At least, with a directional antenna, the gain of the off axis signals is gratly reduced.

dkyork

11-10-04, 10:04 AM

Originally posted by greywolf
Omnidirectional antennas are generally not a good idea due to acceptance of reflected signals from nearby objects. Attic mounting one is a very bad idea. Signal reflections from the attic surfaces come in out of phase and cause havoc. At least, with a directional antenna, the gain of the off axis signals is gratly reduced.

I bought a 4228 and a 6 foot mast for the top of my roof. I'll let you all know how it goes after the install. Hopefully I'll receive by this weekend. Should I get one of those things that tell you the degrees or will a simple compass do for aligning the antenna?

Dale

sregener

11-10-04, 11:22 AM

Originally posted by dkyork
Should I get one of those things that tell you the degrees or will a simple compass do for aligning the antenna?

What, other than a compass, tells you the degrees? You point it north, you can figure out which direction is 270 degrees, right?

As for aligning an antenna with a compass (or any other magentic device) I would urge caution. Aiming an antenna precisely usually cannot be done visually. Hold your fist out at arm's length and see how much distance it covers. That's approximately 10 degrees. With a directional antenna, 5 degrees is more than enough to impair reception.

I always suggest having a television up with you while aiming, or be able to speak with someone (cell phone/walkie-talkie) who can see the reception guide you. That way you're not guessing at all - you know you've found the best direction for the antenna.

sregener

11-10-04, 11:27 AM

Originally posted by Nitewatchman
While it is true the signal itself won't get any "stronger" than is the case at the antenna, it is possible that a preamp CAN lower the over all noise floor that front end of receiver "sees", therefore, in a practical sense, a good preamp(in the right circumstances) can "raise" the overall S/N ratio.

This would seem to confirm what I claimed: that a preamplifier really only overcomes line loss. (Granted, there's a small amount of receiver-induced noise, but there's also a small amount of noise induced by the preamplifier's input itself. Which is greater depends on a variety of things, but I've read claims that a preamplifier's induced noise level is not dramatically different from most tuners.)

dkyork

11-10-04, 12:21 PM

Nitewatchman

11-10-04, 12:36 PM

Originally posted by sregener
This would seem to confirm what I claimed: that a preamplifier really only overcomes line loss. (Granted, there's a small amount of receiver-induced noise, but there's also a small amount of noise induced by the preamplifier's input itself. Which is greater depends on a variety of things, but I've read claims that a preamplifier's induced noise level is not dramatically different from most tuners.)

I don't know what the typical noise figure is for your run of the mill ATSC receiver/tuner, as the below info is talking about NTSC tuner. but FWIW, I copied the below quotes from the link with some of the sections I suggested for reading which I provided in an earlier post, but I suggest you check also out the remainder of the relevant sections at this link : ( http://www.geocities.com/toddemslie/UHF-TV-DX.html )

:quote

"Let's assume that we are not using any UHF masthead preamplifier and there is 4dB coax cable loss between the antenna and TV:

1. Balun signal loss 1dB.
2. Coax cable loss 4dB.
3. TV tuner noise figure 10dB.
4. System noise figure 16dB (1+4+10 = 15).
5. A 15dB system noise figure is a poor receiving system for deep fringe UHF TV reception.

Now let's assume that we are using a 2dB noise figure UHF masthead preamplifier, 1dB loss balun, and there is 4dB coax cable loss between the antenna and TV. The following table will help you appreciate the significant improvement to weak signals by placing a low noise amplifier at the masthead:

Typical UHF TV tuner noise figure 10db 2610 deg Kelvin
20 meters of RG6 coax cable 4.0db 439deg kelvin
Typical balun transformer loss 1.0db 75deg kelvin
4 x belling lee connectors 0.25db 17deg kelvin
Total losses 15.25 dB 9000deg kelvin

In the above example the Receiver System Sensitivity equates to 15.25 dB or 9000 K°.

Now we will add a low noise preamplifier (LNA) right at the masthead (antenna terminals):

Masthead LNA 2.0db 150 deg kelvin
Typical balun transformer loss 1.0db 75deg kelvin
4 x belling lee connectors 0.25db 17deg kelvin
Total losses 3.25 dB 330 deg kelvin

Providing the gain of the LNA exceeds the losses between it and the receiver (TV set), the above losses are negligible.

In the above example (with a LNA at the antenna feed) the receiver system sensitivity equals 3.25 dB (330 °K). This translates to a very significant 12 dB improvement. In other words, your UHF antenna array equates to a net improvement of making the antenna FOUR times as large!

:end quote

mws6468

11-10-04, 01:32 PM

Does anyone have suggestion on an antenna to receive freq's 7,18, 24,34,& 42. I am looking for something that is not very "tall" for I will be mounting it in my apt for at least a couple months. I looked at the winegard HD7210P (http://www.winegard.com/offair/pdf/hd7210p.pdf) . Any suggestions on this or a similar product?

forgot .. i am about 15 miles from towers

mws6468

11-10-04, 02:18 PM

has anyone tried the new PA 16 (http://www.antennasdirect.com) from ant. direct? How does it compare with a CM 7777 or 7778?

cpcat

11-10-04, 08:03 PM

Yes, I agree. In fact, I believe I said that in first sentence of last post.

Yes, you did. Sorry about that.

rwantennasat

11-10-04, 10:05 PM

Originally posted by Nitewatchman
I don't know what the typical noise figure is for your run of the mill ATSC receiver/tuner, as the below info is talking about NTSC tuner. but FWIW, I copied the below quotes from the link with some of the sections I suggested for reading which I provided in an earlier post, but I suggest you check also out the remainder of the relevant sections at this link : ( http://www.geocities.com/toddemslie/UHF-TV-DX.html )

:quote

"Let's assume that we are not using any UHF masthead preamplifier and there is 4dB coax cable loss between the antenna and TV:

1. Balun signal loss 1dB.
2. Coax cable loss 4dB.
3. TV tuner noise figure 10dB.
4. System noise figure 16dB (1+4+10 = 15).
5. A 15dB system noise figure is a poor receiving system for deep fringe UHF TV reception.

Now let's assume that we are using a 2dB noise figure UHF masthead preamplifier, 1dB loss balun, and there is 4dB coax cable loss between the antenna and TV. The following table will help you appreciate the significant improvement to weak signals by placing a low noise amplifier at the masthead:

Typical UHF TV tuner noise figure 10db 2610 deg Kelvin
20 meters of RG6 coax cable 4.0db 439deg kelvin
Typical balun transformer loss 1.0db 75deg kelvin
4 x belling lee connectors 0.25db 17deg kelvin
Total losses 15.25 dB 9000deg kelvin

In the above example the Receiver System Sensitivity equates to 15.25 dB or 9000 K°.

Now we will add a low noise preamplifier (LNA) right at the masthead (antenna terminals):

Masthead LNA 2.0db 150 deg kelvin
Typical balun transformer loss 1.0db 75deg kelvin
4 x belling lee connectors 0.25db 17deg kelvin
Total losses 3.25 dB 330 deg kelvin

Providing the gain of the LNA exceeds the losses between it and the receiver (TV set), the above losses are negligible.

In the above example (with a LNA at the antenna feed) the receiver system sensitivity equals 3.25 dB (330 °K). This translates to a very significant 12 dB improvement. In other words, your UHF antenna array equates to a net improvement of making the antenna FOUR times as large!

:end quote THIS LOOKS LIKE WORK THAT BOB COOPER DID YEARS AGO PROVING HOW MUCH A MAST MOUNTED PREAMPLIFIER DOES ACTUALLY INCREASE THE ANTENNAS PERFORMANCE. I AM A PERSONAL FRIEND OF BOBS AND ANYONE ON HERE WANTING TO KNOW THE TRUTH OF PREAMPLIFIERS SHOULD READ HIS TECH ARTICLES.

EricfromVA

11-11-04, 06:25 AM

I installed my PR8800 in my attic and without an amp was able to pick up my local OTA stations from DC with no problem. Signal was above normal but not pegged. I bought the CM7775 amp based on my past experiences.

I hook up the power source (to TV , from Antenna) I then go in the attic and hook up the pre amp and the signal drops. Is there a short on the line? I have reterminated my drops multiple times and even tried a different CM7775 and the same thing happens. What would effect the power going from the source to the preamp? Shielding touching a termination? Interconnects?

I am at a loss. My signal is decent without it but I know these amps can get me pegged in the good range.

Any and ALL help would be appreciated.

sregener

11-11-04, 09:20 AM

Originally posted by EricfromVA
I installed my PR8800 in my attic and without an amp was able to pick up my local OTA stations from DC with no problem. Signal was above normal but not pegged. I bought the CM7775 amp based on my past experiences.

[...]I am at a loss. My signal is decent without it but I know these amps can get me pegged in the good range.

Preamplifiers are not magic. They don't always improve reception, nor do they even leave it the same in some cases. Among the possibilities:

1) Your preamplifier is getting overloaded because the db level is too high. (All preamps have a maximum output and "clip" if the signal becomes stronger than this.)

2) Your preamplifier is amplifying weak multipath signals that were below your receiver's noise threshold, increasing the errors in the bitstream.

I'm sure there are others, but these are the obvious ones. Keep in mind that "signal strength" on your HD set is an improperly labeled guide. It is really a "signal quality" measure. As long as you're getting breakup-free reception, your reception is already as good as it's going to get. More signal strength on the meter doesn't get you a better picture.

Check your analog UHF signals with and without the preamplifier and see if you can tell what the problem is. My personal recommendation would be to return the preamp and enjoy your quality reception without worrying about "pegging" out the meter.

JazzGuyy

11-11-04, 09:41 AM

I have decided that I need a rooftop antenna. Both a Silver Sensor and the RS indoor antenna I have tried just won't lock reliably enough on all the local channels. While I have cable HD, I don't expect to see the CBS and Fox stations added any time in the near to intermediate future so need reliable OTA reception. My TV is a 2002 Mitsubishi RPTV with a builit-in HD OTA receiver. It does not have signal strength metering.

I live in Goochland, near the J Sargent Reynolds campus. I have checked the usual antenna internet spots but the answers there are not specific enough for me.

I have four questions that I am looking for help on:

1. What outdoor antennas are people finding effective? I would like to also receive Charlottesville stations (can get the HD signal now from the NBC affiliate on an indoor antenna but not reliably) and will probably add a rotator to the antenna.

2. Do you think I will need an amplifier?

3. Can anyone recommend an installer? I am too short on skills to do the install myself. You can PM me on this last question, if you don't want to be seen as endorsing anyone.

4. What should a good antenna, rotator and maybe amplifier cost me, installation included?

Thanks in advance for any help you can give me.

sregener

11-11-04, 12:06 PM

Originally posted by JazzGuyy
1. What outdoor antennas are people finding effective? I would like to also receive Charlottesville stations (can get the HD signal now from the NBC affiliate on an indoor antenna but not reliably) and will probably add a rotator to the antenna.

2. Do you think I will need an amplifier?

3. Can anyone recommend an installer? I am too short on skills to do the install myself. You can PM me on this last question, if you don't want to be seen as endorsing anyone.

4. What should a good antenna, rotator and maybe amplifier cost me, installation included?

1. You can read this thread for lots of antenna recommendations. Generally speaking, you can't go wrong with the Channel Master 4228 or AntennasDirect DB8. Both are solid UHF performers, highly directional, with a lot of gain and good front-to-back ratio. (If you don't know why those things matter, don't worry. They're all what you want in an antenna.) Add to that the relatively compact size of these antennas, and they get recommended a lot.

2. An amplifier is not recommended when you're within 20 miles of the stations, or you have a large number of high-powered FM broadcasters in the area. If you're hiring an installer, have them bring a good low-noise model (the Channel Master 777x lineup is a great choice) with them and see if you need it. How will you know? Look for snow on the analog UHF channels in your area. If you have lots of snow, a preamp is a good idea. If you have even the faintest ghosting, forgo the preamp.

3. You may have more luck asking for an installer in the thread specific to your market.

4. A Channel Master 4228 runs about $50 online (plus shipping.) A 7775 preamp costs $55. A Channel Master 9521A rotor runs $70. Toss in a mast, 100' or so of RG-6 cabling, a mount, and some sundry items, and your materials cost shouldn't be more than $250. I couldn't guess what labor runs in your area.

Antennaweb.org thinks you're borderline (violet) for analog UHFs from Charlottesville, so your results may vary. The distance is small (35 miles or so) but there must be hills or directional antennas there that make it harder to receive them. Still, if you're getting a somewhat reliable signal indoors, you should be able to receive the same station from a rooftop reliably.

dkyork

11-11-04, 11:23 PM

15.1, 15.2, 15.3, 15.4 WHRO-DT PBS HAMPTON-NORFOLK 199° 28.2 Excellent 16
43.1, 43.2 WVBT-DT FOX VIRGINIA BEACH 200° 27.4 Excellent 29
10.1, 10.2, 10.3 WAVY-DT NBC PORTSMOUTH 200° 27.4 Excellent 31
33.1, 33.2 WTVZ-DT WB NORFOLK 199° 28.2 Excellent 38
3.1, 3.2 WTKR-DT CBS NORFOLK 199° 28.2 Excellent 40
13.1, 13.2 WVEC-DT ABC HAMPTON 195° 27.3 Excellent 41
49.1 WPXV-DT PAX NORFOLK 199° 28.2 Excellent 46
27.1 WGNT-DT UPN PORTSMOUTH 194° 27.7 Excellent 50

That my listing from antenna.org. How can I get 10.1 in clearly 24/7, but I can't get 43.1? They are the same degrees and the same distance. I don't understand. Can anyone help me? I still don't get 3.1 or 33.1. I get all the 15s, 10s, and sometimes 13s. None of the rest. IS this a distance problem? The results just aren't logical or I'm misunderstanding something about how antennas work. Any help appreciated. The 43.1 and 10.1 thing is really throwing me off.

Thanks,

Dale

Edit: D* installed a GS-2200 Winegard, which is currently up. I received in the mail today a 4228 and a 5 foot mast. I have yet to install it since I don't have the right roof mounts yet. I'm trying to install near my peak of the house, any suggestions welcome.

Edit #2: Also, this might be harder a task then I think it is. If so, can anyone recommend a good installer to mount this thing on my roof?

L8N8

11-11-04, 11:47 PM

I'm making my first venture into the foray of OTA reception.

I just bought a MyHD-120 ATSC card, replacing the FusionHDTV3-T card I bought two weeks ago (I wasn't satisfied with the PQ of the Fusion card).

Now, I've already done a bit of reception testing with the Fusion card and a Zenith Silver Sensor (which I also have since returned). I put the Silver Sensor in the attic pointing toward the HD antennas in my area (Austin) as indicated by antennaweb.org.

I think the results were pretty good, considering I'm about 14 miles from the antennas. I was able to get one station at 80% signal strength (according to the Fusion card) and another at 70%. Some of the others I couldn't tune at all (but antennaweb says a green antenna should do the trick).

So, I'm just looking for a little help to decide what antenna to get.

My local Fry's has a Channel Master 3017 in stock. Will that do the trick do you think? Will it pick up VHF channels pretty effectively as well (FOX is on channel 7). Will I run into trouble if I get *too* much antenna? (Is that even possible?)

Also, the MyHD card has two F-type inputs. Do I need two antennas if I want to use both inputs?

Thanks!

mws6468

11-12-04, 09:59 AM

which preamp would be recommended to use with a DB2 (http://www.antennasdirect.com/db2_bowtie_antenna.htm) ?

sregener

11-12-04, 10:26 AM

Originally posted by dkyork
43.1, 43.2 WVBT-DT FOX VIRGINIA BEACH 200° 27.4 Excellent 29
10.1, 10.2, 10.3 WAVY-DT NBC PORTSMOUTH 200° 27.4 Excellent 31

That my listing from antenna.org. How can I get 10.1 in clearly 24/7, but I can't get 43.1? They are the same degrees and the same distance. I don't understand. Can anyone help me?

A few possibilities exist.

First, WVBT's transmitter is 40 meters lower than WAVY's. If you're dealing with hills, it is entirely possibile that WVBT's signal is running smack into the hill (blocking line-of-sight) while WAVY's is clearing it.

Secondly, assuming both signals are blocked, different frequencies propogate in different ways, and some signals will be strong in one area and weak in another. Ultimately, you end up searching for a "pocket" where the most signals are hitting, a so-called "hot spot" and place your antenna there. It may be to the left or right of where you think it should be, or maybe up or down. UHF signals only move about 3' from peak to valley, so we're dealing with a pretty small area in which a stray signal could be found.

Third, you may be picking up a reflection on WVBT that you're not getting from WAVY. This is called multipath (because the signal travels over multiple paths before striking your antenna) and since the distances are unequal, the two signals are out-of-phase. Again, because different frequencies propogate differently, you may find a reflection on one frequency that you don't have on another. Multipath is known to confuse most digital receivers, and the level of multipath required may vary from place to place.

Fourth, WVBT is using a directional antenna, and if it malfunctioning, it may not be sending out the specified power in your direction. Check with the station engineer to verify that the transmitter is running at full power and that the directional pattern is operating normally.

Finally, you may have some form of interference that is causing problems on one frequency and not on another. If there is another station on a near frequency (one channel up or down) it can sometimes interfere with reception of another channel. Although this problem is greatly reduced with digital signals, there is some amount of "bleed" from one channel to the next.

Hope this helps you understand how things can be different. I don't know the topography between you and your desired stations.

bobbehr

11-12-04, 11:33 AM

Winegard HD9095P vs.Antennasdirect 91XG
Location: South Haven,MI 49090
Desire:Maximum Uhf signals for OTA HD.Mainly South Bend,also 2 and
7 from Gun Lake,and any Chicago on the good days.
Additional tips welcome.Thanks to the Best

sregener

11-12-04, 12:23 PM

Originally posted by bobbehr
Winegard HD9095P vs.Antennasdirect 91XG
Location: South Haven,MI 49090
Desire:Maximum Uhf signals for OTA HD.Mainly South Bend,also 2 and
7 from Gun Lake,and any Chicago on the good days.
Additional tips welcome.Thanks to the Best

Neither will do an acceptable job on channel 2. You *might* get away with trying to get 7 with a UHF-only, but that's not a guarantee. Your best bet would be to buy a VHF-only antenna to combine with one of the above choices and use a Channel Master #0549 (or a preamplifier with separate UHF and VHF inputs like the CM 7777) to combine the two.

If you haven't read my review of the AntennasDirect91XG, do so here:
http://www.geocities.com/figbert/91xg.html

The 9095 is a good choice. I can't say if it's better than the 91XG. Others have reported better results with the 91XG or the DB8, and some swear by the 9095. I think you'd best try them both and see which one works better in your particular location.

bobbehr

11-12-04, 08:22 PM

Yea sorry ,
"also" after South Bend should have read "don't care about 2 or 7".
"and any Chicago" should read "any Uhf Chicago"
Poorly written post ,of course I don't expect any Vhf signals.
Many thank you's sregener.

dkyork

11-12-04, 10:18 PM

Grounding an antenna properly. Does the Winegard GS-2200 have grounding to the HD tuner? I looked at the Winegard D* installed and didn't see a copper grounding wire. I think when I put the 4228 in it's place, I'll need a copper grounding wire right?

thanks,

Dale

greywolf

11-12-04, 10:29 PM

http://www.mikeholt.com/documents/grounding/word/satellite.doc

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=395088

AVSforum member Signal posted the following helpful sites. Dish and antenna masts have the same grounding requirements.

National Electrical Code - Search for "dish" http://forums.nfpa.org:8081/necfaq/necsrch.htm

The information there also applies to antenna grounding. In the 2002 code update, if a water pipe is used, it must be all metal and connected to the electrical panel within 5ft of where the pipe enters the building. The connection to the pipe from the lightning arrestor/ground block and from the antenna/dish mast must also be within 5ft of the pipe's entry.

Preventing Damage Due to Ground Potential Difference
http://www.cinergy.com/surge/ttip08.htm

PSIHQ - Grounding Requirements
http://www.psihq.com/iread/strpgrnd.htm

PolyPhaser Technical Information
http://www.polyphaser.com/ppc_technical.asp

dkyork

11-13-04, 12:03 AM

Originally posted by greywolf
http://www.mikeholt.com/documents/grounding/word/satellite.doc

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=395088

AVSforum member Signal posted the following helpful sites. Dish and antenna masts have the same grounding requirements.

National Electrical Code - Search for "dish" http://forums.nfpa.org:8081/necfaq/necsrch.htm

The information there also applies to antenna grounding. In the 2002 code update, if a water pipe is used, it must be all metal and connected to the electrical panel within 5ft of where the pipe enters the building. The connection to the pipe from the lightning arrestor/ground block and from the antenna/dish mast must also be within 5ft of the pipe's entry.

Preventing Damage Due to Ground Potential Difference
http://www.cinergy.com/surge/ttip08.htm

PSIHQ - Grounding Requirements
http://www.psihq.com/iread/strpgrnd.htm

PolyPhaser Technical Information
http://www.polyphaser.com/ppc_technical.asp

Ugh, neither my Dish or OTA antenna is grounded. This is going to be fun. Guess I need to go buy about a 100 foot of copper wire and figure out how to ground these the best way.

Thanks for the links.

Dale

sregener

11-13-04, 08:41 AM

Originally posted by dkyork
Ugh, neither my Dish or OTA antenna is grounded. This is going to be fun. Guess I need to go buy about a 100 foot of copper wire and figure out how to ground these the best way.

You can ground your antenna by connecting a short length of wire from the mast to the outer shealth of the coax cable, then ground the coax with a grounding block at the point closest to where it enters the house. Then you don't have so much cable to run.

greywolf

11-13-04, 09:54 AM

That wouldn't satisfy code requirements though. No. 10 copper, No. 8. aluminum, or No. 17 copper-clad steel or bronze is specified. Using coax with an attached messenger wire will meet code as it is 17ga copper clad steel or bronze. http://www.globe-mart.com/page/5/5722.htm shows an example.

dkyork

11-14-04, 09:45 AM

greywolf

11-14-04, 09:47 AM

Sounds workable. The odd thing though is sregener's idea actually provides a cleaner, lower resistance path to ground. Maybe the code writer's never considered it or they worried about poor connector installation. My only objection involves exposed coax connectors. I like mine out of the weather. OTOH, the contact hardware on ground clamps and blocks is pretty foolproof.

Woo

11-14-04, 08:42 PM

I have a newbie antenna question....I bought a l UHF/VHF antenna for an attic mount. The problem arose when I attempted to orient this large antenna in the direction required but I can't turn it enough because of the VHF extensions. My question is since I'm only interested in UHF, can I fold those extensions inward and not have it affect the UHF performance?

Thanks & Regards,
Woo

cpcat

11-14-04, 11:40 PM

My question is since I'm only interested in UHF, can I fold those extensions inward and not have it affect the UHF performance?

Yes, just don't let any of the parts you fold in touch the rest of the antenna.

sregener

11-15-04, 10:20 AM

Originally posted by greywolf
That wouldn't satisfy code requirements though. No. 10 copper, No. 8. aluminum, or No. 17 copper-clad steel or bronze is specified. Using coax with an attached messenger wire will meet code as it is 17ga copper clad steel or bronze. http://www.globe-mart.com/page/5/5722.htm shows an example.

As usual, code isn't written with common sense in mind.

If there is a lightning strike within 10' of your antenna (or, obviously, the antenna itself), all the electrical equipment in your house is likely to be fried no matter how well grounded it may be. Grounding is required not to take care of distributing electrical charges in such a circumstance, but to "bleed off" static buildup that is caused when charged wind particles are blown around a metal object.

Now, I'm not an electrician, but it seems to me that the amount of static buildup on an antenna can't be that much that it would require a #10 copper wire to carry the electrical charge. Thus, almost any wire should be sufficient to protect against the voltage differential between the ground and the metal object.

In my previous recommendation of attaching the grounding wire to the outer coax connection, there is no reason that you can't seal that connection using electrical tape, protecting it from the elements.

Of course, following my advice (or that of anyone else posting on the internet) is at your own risk, and I make no claims that my proposed solutions are effective, safe, or even a good idea. Caveat reader.

greywolf

11-15-04, 11:04 AM

I figure a lot of code regulations are written to support the trades rather than addressing actual safety and security issues. If 17ga copper coated steel is a good enough conductor to bleed off static, the shield of the coax is certainly even better. I always recommend people check local codes as they vary and noncompliance can cause problems with insurance and resale if not function. My personal irritations around local codes include not being able to use non-metallic sheathed electrical cable in any situation or plastic plumbing pipe in many situations even though they work fine and are accepted in most areas.

cpcat

11-15-04, 12:16 PM

As usual, code isn't written with common sense in mind.

It also would follow that the difference in earth potential and the potential of the house ground would be small enough to render the difference insignificant in practice. However, as most know, the code states you must strap to the house ground and not simply to earth.

I'm not an electrician, either, and the same "caveat reader" applies.

ross86

11-15-04, 12:41 PM

is HDTV available in the UK?

greywolf

11-15-04, 01:25 PM

Originally posted by cpcat
It also would follow that the difference in earth potential and the potential of the house ground would be small enough to render the difference insignificant in practice. However, as most know, the code states you must strap to the house ground and not simply to earth.

I'm not an electrician, either, and the same "caveat reader" applies. In case of a nearby lightning strike, the potential difference between the main building ground and other spots in the earth can be pretty large and dangerous so I understand necessity of bonding separate gound points. http://www.cinergy.com/surge/ttip08.htm

To continue the rant though, even supposed professionals screw up the interpretation of the electrical code. I was watching "House Detective" on HGTV and a certified home inspector saw a ground connection from the incoming CATV line attached to the grounded metallic electrical service raceway of the house. He said it was a code violation, had been outlawed by the NEC for years, and could cause dangerous situations including exploding a VCR. In fact, The NEC says acceptable central building ground points include:

* Grounded interior metal cold water pipe within five feet of the point where it enters the building.
* Grounded metallic service raceway.
* Grounded electrical service equipment enclosure.
* Eight-foot grounding rod driven into the ground (only if bonded to the central building ground by #6 or heavier bonding wire).

cpcat

11-16-04, 08:03 AM

I understand what is recommended by code, and I know there are multiple sources out there agreeing with that. What I've not seen is any proof that grounding to the house ground is safer than earthing in the most direct manner possible. The problem is that most if not all the info on lightning strikes is anecdotal/theoretical. It would seem to me that the following methods would be ranked in order of safe methods with the safest #1:

1) Direct path to earth with grounding rod strapped to house ground.
2) Direct path to earth with grounding rod
3) Ground to house ground.

I've spoken to 2 local electricians now and they both told me they'd go with #2 above.

Again, "caveat reader" and #2 above is *not* in compliance with NEC.

greywolf

11-16-04, 09:17 AM

1 would be best for a direct hit.
3 would be best for a nearby hit.
2 is just plain dangerous. The electricians you talked to weren't even thinking about what could happen in a nearby strike.

A direct hit though is very unlikely with a grounded mast and a direct hit is going to cause damage no matter how straight and short the path to ground. The purpose of grounding is prevention.

mitchlampert

11-17-04, 09:40 AM

If I want to combine the satellite (triple LNB) with the antenna cables to run one cable to the reciever, what do I need? And what do I need to seperate them at the reciever?

Thanks
Mitch

dswallow

11-17-04, 11:15 AM

Originally posted by mitchlampert
If I want to combine the satellite (triple LNB) with the antenna cables to run one cable to the reciever, what do I need? And what do I need to seperate them at the reciever?
You want to use a diplexer at each side.

virgil001

11-17-04, 05:02 PM

Has anyone ever posted a general guide on amps and pre-amps, and the more popular models? If so, would someone point me in the right direction, please?

Mach5

11-18-04, 01:57 AM

Hi,

I live 2.5 miles south of ESB, Lower E. Side, I can't get 2.1(cbs) and 4.1(nbc) at all. I can only recieve 5.1-2 (fox), 7.1-2 (abc) and sometime 11.1-2 (wb). I have medium range direction antenna on the roof (5 stories building) and Sony TV with ATSC tuner built in. My question is if I get a TV antenna amplifier, will it help?? Recommendation on which type to buy??

w9wi

11-18-04, 09:36 AM

If you're only 2.5 miles from the ESB, weak signals shouldn't be your problem - and an amplifier won't fix anything. Indeed, it can make things *worse*, by overloading and causing stations to appear on channels they aren't actually broadcasting on.

It would be interesting to know what the *analog* reception on the same antenna looks like. Check analog *UHF* channels - it's my understanding WNYE (25), WPXN (31), WXTV (41), and WFUT (68) are all on the ESB.

If your analog reception is weak, with "snow" across the entire screen, then there's something wrong with your antenna or (more likely) the feedline connecting it to the TV.

If your analog reception has "ghosts" - multiple images - then you're going to have to fiddle with the antenna. Try turning it to minimize the ghosts -- the correct orientation may *NOT* be with the antenna pointed at the ESB! (you should have plenty of spare signal; you should be able to weaken the desired signals if you weaken the unwanted reflections even more) Ghosts can also be caused by defects in the antenna or feedline. Unfortunately, it's also possible you simply won't be able to achieve acceptable reception, if there's a large building between you and the ESB.

If your analog reception has some other kind of noise in it -- other than "snow" -- that's caused by a local source of interference. This kind of problem is usually worse on lower channels - the noise should be much worse on analog channel 2 than it is on analog channel 41. Unfortunately this kind of interference can be difficult to locate...

(I wonder how we're going to track down reception problems when the analog transmitters are shut down?!)

IndyJake

11-18-04, 10:29 AM

I need some help.

First, the questions. Can I stack two dissimilar antennas? If so, how is best to do it? Vertical? Horizontal? Would I need separate pre-amps for each?

Now the background. I live on a farm outside Clinton, IN 47842. I need VHF and UHF reception. My signal sources come from the south (16 to 32 miles), west (35 to 60 miles) and east (65 to 68 miles). The terrain is flat. I already have a 40' tower, a Channel Master 4242 UHF/VHF antenna, a Channel Master 7777 pre-amp and a Channel Master rotator. I'm usiing Sony HD-300 and DirecTV HR10-250 receivers. (The Sony, by the way, locks on OTA signals much better).

I want to add a Channel Master 4228 UHF antenna to my existing 4242 to increase my long distance UHF reception. Is this doable???

Thanks in advance to any of you who can educate me.

sregener

11-18-04, 12:22 PM

Originally posted by IndyJake
First, the questions. Can I stack two dissimilar antennas? If so, how is best to do it? Vertical? Horizontal? Would I need separate pre-amps for each?

You "can" do many things that won't work. This is one of them.

The best thing to do is to hook the two separate antennas to an A/B switch and switch between them for your different reception situation.

Hooking up two UHF antennas (identical or not) and pointing them in different directions almost always reduces your received signal strength, not increases it. (Note: this age-old "wisdom" might change when the new LG 5th-generation chipset becomes available.)

IndyJake

11-18-04, 12:31 PM

Hooking up two UHF antennas (identical or not) and pointing them in different directions almost always reduces your received signal strength, not increases it.

I may not have been clear on this. I intended to point both antennas in the same direction and use the rotator when a change in position was needed. My purpose in stacking was to get better UHF reception, not to get reception from different directions at the same time.

GenoV

11-18-04, 01:19 PM

Jake,

I've got a 4228 and a 3671 ChannelMaster stacked and pointed in the same direction, running through a 7777 pre-amp, and it works fine. Whether or not it is boosting the reception, I couldn't tell you because I've never run them separate from one another. But the point is, it does work and doesn't seem to hinder any reception as far as I can tell.

cpcat

11-18-04, 04:14 PM

I may not have been clear on this. I intended to point both antennas in the same direction and use the rotator when a change in position was needed. My purpose in stacking was to get better UHF reception, not to get reception from different directions at the same time.

IndyJake,
If you want to stack for increased gain and/or directivity you'll need two identical antennas. Vertical stacking narrows vertical beamwidth while horizontal stacking narrows horiz. beamwidth. You'll need identical lengths of coax before the combiner. Specialty uhf combiners are available, but a wideband splitter in reverse also works. You might also consider upgrading to a single Antennasdirect XG91 first which is likely to be a small but significant improvement on a single 4242 on the uhf side. Sregener has a review of one : http://www.geocities.com/figbert/antennasdirect91xg.html

I prefer horizontal stacking for digital reception. I've tried vertical multiple times and I always return to horizontal. I'm 65-130 mi. away. Vertical also puts mucho stress on the rotor so you'll need an alignment bearing or a heavy duty rotor if you go vertical.

I've got a 4228 and a 3671 ChannelMaster stacked and pointed in the same direction, running through a 7777 pre-amp, and it works fine. Whether or not it is boosting the reception, I couldn't tell you because I've never run them separate from one another. But the point is, it does work and doesn't seem to hinder any reception as far as I can tell.

GenoV,
I'd bet the reason this works is that you're hooked to the separate uhf and vhf inputs on the CM7777 and it's diplexing out the uhf signals from the 3671.

IndyJake

11-18-04, 04:36 PM

Thanks cpcat,

I guess I'm stuck with what I've got for the time being as I can't give up the VHF yet.

cpcat

11-18-04, 04:45 PM

IndyJake,
If you can do with high band vhf (7-13) only you could separate them i.e. xg91 for uhf and something like an antennacraft Y107-13 for vhf high band. This will work perfectly using the CM7777. If you need low band, better stay with the monster you have.

Rmassey

11-18-04, 08:49 PM

I have a Reconton TV2000 (http://products.consumerguide.com/reviews/product.epub?productId=18243) that I purchased and installed in 1999. Is this suitable for HDTV reception. I live in Colorado Springs and I am currently only getting CBS, and FOx is very blocky and breaks up a lot. Do I just need to adjust the direction/location of the antenna to get better reception?

sregener

11-18-04, 10:36 PM

Originally posted by IndyJake
I guess I'm stuck with what I've got for the time being as I can't give up the VHF yet.

You *can* stack two dissimilar antennas together, if you're willing to do a lot of work and only need one channel. Essentially, you vary the lengths of the cable between each antenna and the combiner until the signal is in phase. Of course, the lengths change by frequency, so what works for one channel won't work for another.

You don't have to give up VHF to use a VHF/UHF combo and a separate UHF antenna. Just get a Channel Master #0549 (or use a Channel Master 7777 preamplifier, though that's probably not a good idea in your case.) Hook the new UHF antenna to the UHF input, hook the old combo to the VHF input, and you're done. The #0549 will, for $10, filter out the VHF extras from the UHF antenna and the UHF side of the combo. If you're using a preamplifier, hook it up just below this combiner.

sregener

11-18-04, 10:39 PM

Originally posted by Rmassey
I have a Reconton TV2000 (http://products.consumerguide.com/reviews/product.epub?productId=18243) that I purchased and installed in 1999. Is this suitable for HDTV reception. I live in Colorado Springs and I am currently only getting CBS, and FOx is very blocky and breaks up a lot. Do I just need to adjust the direction/location of the antenna to get better reception?

It's probably not a very good antenna for digital reception. You'd do better to get a "normal" antenna from a reputable manufacturer (Winegard/Channel Master) and use that. That said, if you haven't tried different aiming directions and locations on your property, that's cheap to do and might help.

Still, I wouldn't bet on reliable reception from that overadvertised, overpriced hunk of junk.

MAX HD

11-18-04, 10:57 PM

Originally posted by IndyJake
I need some help.

First, the questions. Can I stack two dissimilar antennas? If so, how is best to do it? Vertical? Horizontal? Would I need separate pre-amps for each?

Now the background. I live on a farm outside Clinton, IN 47842. I need VHF and UHF reception. My signal sources come from the south (16 to 32 miles), west (35 to 60 miles) and east (65 to 68 miles). The terrain is flat. I already have a 40' tower, a Channel Master 4242 UHF/VHF antenna, a Channel Master 7777 pre-amp and a Channel Master rotator. I'm usiing Sony HD-300 and DirecTV HR10-250 receivers. (The Sony, by the way, locks on OTA signals much better).

I want to add a Channel Master 4228 UHF antenna to my existing 4242 to increase my long distance UHF reception. Is this doable???

Thanks in advance to any of you who can educate me.

Your desire to improve UHF reception indicates you are having problems.Which stations are weak or problematic?

IndyJake

11-18-04, 11:47 PM

Max HD:

You may regret asking that question. The short answer is that I'll know in a week.

Here's the long answer. I just moved in to my new home from the trailer I was living in next door while I built it. Just prior to moving, The CM 4242 received a direct lightning strike (frying all my receivers, my computer, my CM 7777 pre-amp, my rotator and my computer) but my antenna installers who wired the house and installed the 40' tower thought the antenna would be ok to use anyway. It's now up there and has a Weingard pre-amp the installers provided.

The lightning strike was my excuse to buy a HR10-250 receiver. But the HR10-250 keeps losing the OTA signals. My Sony HD-300, however, doesn't. Soooooo, DirecTV has sent out two replacement HR10-250's, has had a tech come out and is scheduled to have a "senior" tech come out next week. My antenna guys have been out a half dozen times as well.

But here's what I've noticed. If I jiggle the coax connection I get a significant increase or drop in signal. It doesn't matter whether I do it at the receiver, at the wall jack, in the mechanical room at the pre-amp, the splitter or anywhere else. It has the weakest signal when all the connections are screwed down tight. But just play with one and the signal's all over the place. Tonight it's good. In the morning I'll probably have to jiggle a wire again. The problem is I don't even know if "good" is good enough because I can't get stations I used get using my old receiver without the tower. Maybe in addition to my other problems the HR10-250 just isn't a very good OTA receiver.

Anyway, my conclusion, since the "experts" haven't been much help thus far, is that I may have a defective pre-amp or I may have some type of interference in my mechanical room. But with that damned antenna sitting up there and having been struck by lightning I've got to eliminate it as a possible cause.

So I have a new CM 4242 arriving Monday along with a CM 7777 pre-amp. We'll be installing them Tuesday and see what happens. My original question about stacking arose because I figured if I'm going to all this trouble to bring down the tower I might as well put up two antennas if it would help.

Thanks for asking. I needed to vent. I'll let you know in a week whether my problem's been solved.

Rmassey

11-19-04, 04:39 PM

Originally posted by sregener
Still, I wouldn't bet on reliable reception from that overadvertised, overpriced hunk of junk.

Ahh OK, thanks, I think..... In my defense, I bought it before I knew any better and/or I had any hopes or knowledge of HD content ;)

Cucuy

11-19-04, 06:48 PM

Hi All,
I live near some railroad tracks that are somehat busy. I have noticed that everytime the train passes it interferes with my HDTV reception. I have a Silversensor and a LG 3510A STB. Is there a way to fight this? Would a better antenna help me? What causes the interference just the noise (probably low frequency wit lots of energy) Or is it something else? It is very annoying when it happens.

greywolf

11-19-04, 07:23 PM

The electrical emissions really are only a pain with the low VHF channels. The antenna can pick up those frequencies in the channel 2-6 range. The SvS is a UHF antenna so that metal mass is the probable culprit. Blocking is a rarer phenomena than reflection. Signals reflecting off the large objects arrive off axis from the direct signal so come in out of phase and have a somewhat cancelling effect.

A typical method to fight multipath is to use a very directional antenna so that off axis refections are very weak compared to the main signal. The SvS is pretty directional and that's a good start but it's usually indoors so the structure reflects a lot of signals. Going outdoors can help.

Two identical, highly directional antennas mounted side by side and aimed in the same direction, combined with a standard two way splitter and equal length coax can do a very good job of ignoring off axis signals. A 5th generation tuner scheduled to arrive first quarter 2005 is reported to be able to analyse the signal streams and combine them in phase.

MAX HD

11-19-04, 07:29 PM

Originally posted by IndyJake
Max HD:

You may regret asking that question. The short answer is that I'll know in a week.

Here's the long answer. I just moved in to my new home from the trailer I was living in next door while I built it. Just prior to moving, The CM 4242 received a direct lightning strike (frying all my receivers, my computer, my CM 7777 pre-amp, my rotator and my computer) but my antenna installers who wired the house and installed the 40' tower thought the antenna would be ok to use anyway. It's now up there and has a Weingard pre-amp the installers provided.

The lightning strike was my excuse to buy a HR10-250 receiver. But the HR10-250 keeps losing the OTA signals. My Sony HD-300, however, doesn't. Soooooo, DirecTV has sent out two replacement HR10-250's, has had a tech come out and is scheduled to have a "senior" tech come out next week. My antenna guys have been out a half dozen times as well.

But here's what I've noticed. If I jiggle the coax connection I get a significant increase or drop in signal. It doesn't matter whether I do it at the receiver, at the wall jack, in the mechanical room at the pre-amp, the splitter or anywhere else. It has the weakest signal when all the connections are screwed down tight. But just play with one and the signal's all over the place. Tonight it's good. In the morning I'll probably have to jiggle a wire again. The problem is I don't even know if "good" is good enough because I can't get stations I used get using my old receiver without the tower. Maybe in addition to my other problems the HR10-250 just isn't a very good OTA receiver.

Anyway, my conclusion, since the "experts" haven't been much help thus far, is that I may have a defective pre-amp or I may have some type of interference in my mechanical room. But with that damned antenna sitting up there and having been struck by lightning I've got to eliminate it as a possible cause.

So I have a new CM 4242 arriving Monday along with a CM 7777 pre-amp. We'll be installing them Tuesday and see what happens. My original question about stacking arose because I figured if I'm going to all this trouble to bring down the tower I might as well put up two antennas if it would help.

Thanks for asking. I needed to vent. I'll let you know in a week whether my problem's been solved.

If by jiggling the coax,and or the connectors is messing with the signal I would definitely make the installers replace every run of wire if need be.Not good.

Since you're going with the 7777,seperate UHF/VHF antennas would be a better way to go,with you trying to pick up Indy,Champaign,Urbana,etc.A CM-4228 with a VHF such as a Delhi VP-307 would be good.

Be sure to post back next week,after they work on it some more.

Chad0429

11-22-04, 04:32 PM

I've got 3 different degrees listed here for my location. 165, 166, 167 - all relative to polar North.

Will one antenna pick up all of these if pointed in the general direction or do I need 3 different antennas? Would an omidirectional do the trick? I think there's one station not listed that I may be able to get and it's probably at the 190ish range. Would I only need 2 antennas then and run some kind of condenser?

Thanks

Chad0429

11-22-04, 06:12 PM

Perfect - sorry for the mispost. Glazed right over this thread.

I'm ~40-45 miles from the source per the site, violet is the type being recommended.

I don't think I can do an outdoor antenna per Homeowners Assoc., but I have about 10 or 12 feet in my attic that I can mount the antenna on a mast and get it up there pretty good.

Any recommendations?

greywolf

11-22-04, 06:30 PM

Check http://www.fcc.gov/mb/facts/otard.html to see if your HOA regulations violate FCC rules. Most do and are null and void.

GHorne

11-23-04, 08:55 PM

Anyone live in San Bernardino County, City of Upland, and able to get a decent OTA signal. I tried it and can barely get a signal. I was wondering if I need to get an antenna placed on the outside of my home rather than the $30 goodguys inside one I currently have.
Garrett

cmk

11-25-04, 01:26 AM

I am relatively new to OTA HDTV. I live in Tualatin Oregon which is 11 miles out from the Towers in Portland Oregon. I first tried Terk's HDTVi and that was garbage. I tried another Terk Product
tv55 and returned that as well. I then tried and RCA boom type antenna RCA ANT3022 mounted in my attic of my 2 story home. The towers are all within 5 degrees of each other so I am thinking I would not need a rotor. At times I get great receiption. Other times it is very intermittent. I later added a Radio Shack high gain antenna mounted preamp 15-2507. This seems to be of no help. My receiver is a Samsung TS360. The OTA signal meter seems to bounce all over the place. Mostly setting on 45%. Sometimes it bounces to zero and I still have a picture?? I have to constantly adjust the antenna. Once I think I have it dialed in great the next day my receiption is intermittent. Any pointers would be a huge help. Am I possibly getting different results based on weather conditions?? This is a great forum.

cpcat

11-25-04, 11:13 PM

All of your digitals are uhf except PAX which is ch. 4. If you can do without PAX, the simplest thing would be to go with something like a CM 4221 (minumum) or better a CM 4228 since you're in the attic (you need a much larger antenna from your attic). I would not use a preamp at that distance.

If you need ch. 4, you could add the antenna you have (only for vhf) and you'll need a vhf/uhf diplexer to combine the two antennas. The diplexer filters out uhf from the vhf antenna and vice-versa for the uhf, preventing corruption of the signal with multipath. A good diplexer is the CM 0549.

Go to http://www.2150.com/broadcast/default.asp for bearing to the towers so you can aim precisely.

cmk

11-26-04, 12:22 AM

Thanks for the advise. Is my current antenna not ideal since it is pickup up both UHF and VHF creating interferance or is is not large enough?? At times it worked great but seems to have breakup during rainy/cloudy conditions on some channels. I'll return the Pre amp and give on of the channel masters you suggest a try

cpcat

11-26-04, 09:44 AM

Your current antenna likely has an insufficient uhf section for consistent performance inside of an attic. The vhf is probably o.k. (at that distance).
If you wanted to keep that antenna for both uhf/vhf, you'd have to go outside with it.

The vhf/uhf interference is only an issue with separate antennas.

Mark McQuaide

11-28-04, 04:19 PM

Hi all,

My Fox digital signal here in SE PA is marginal, and I've noticed that any electrical appliances like the washer or kitchen mixer, or just unplugging an electrical cord from the wall, will cause a dropout of the signal. Is there anything I can do to reduce this, like putting in upgraded coax from my attic antenna? The coax was installed when the house was built and I don't know what the quality is.

I'm using a Channel Master 8-bay UHF antenna and a Winegard preamp with a Sony HD-100 HD receiver. Everything is plugged into a Monster HTS 1100 power conditioner. Any tips would be appreciated.

Mark

bcolon

11-28-04, 07:01 PM

I recently added a Leviton Powered amp to my antenna line to strengthen my signal, but it had the opposite affect. Half of my HD stations had lost their signals and all of my SD channels had snow. Any ideas on what is wrong?

Rmassey

11-28-04, 11:01 PM

Originally posted by sregener
It's probably not a very good antenna for digital reception. You'd do better to get a "normal" antenna from a reputable manufacturer (Winegard/Channel Master) and use that. That said, if you haven't tried different aiming directions and locations on your property, that's cheap to do and might help.

Still, I wouldn't bet on reliable reception from that overadvertised, overpriced hunk of junk.

hey guess what, I re-pointed this "overadvertised, overpriced hunk of junk." to the south and I now get all the OTA locals via HD. Thanks for the valuable advise. :p

blackngold19

11-29-04, 08:31 AM

I know this post should be in the BOSTON MA OTA FORUM, but I've posted about my issues there to no avail. I am 35 miles away from the towers in Boston, and I currently have the Square Shooter antenna on my bedroom window terrace about 25' high. This is where my landlord allows me to keep my dishes, so I really can't go higher or bigger in size. I am running 50' of cable to my tuner. Here is a breakdown of my current signal strengths from best to worst.

CBS - 80-82%
ABC - 75-78%
PBS - 72-75%
NBC - 60-68%
FOX - up to 65% tough to lock in for long periods of time
UPN - up to low 60% only locked on it once

Should I just accept what I currently have under my current constraints, or can more tweaking or premaps possibly help my situation? If a preamp will help, is it easy to wire the plug into the house? A plug would be very close through and adjacent wall where the cable runs in. Maybe FOX and UPN are just weaker signals. If a drop of rain or cloud rolls by it's gone. All antenna compass points are between 90-92% according to antennaweb.

Any advice would be greatly appreciated.

Thanks,

blackie

sregener

11-29-04, 10:39 AM

Originally posted by blackngold19
Should I just accept what I currently have under my current constraints, or can more tweaking or premaps possibly help my situation? If a preamp will help, is it easy to wire the plug into the house?

A preamplifier might help. They come in two pieces - an indoor unit and an outdoor unit. The indoor unit plugs into the wall, preferably close to the television, and "injects" the power up the coax to the outdoor unit.

But preamplifiers won't help if multipath is the problem. Check your analog UHF signals for ghosting. If you see ghosts, more power isn't likely to fix your problem.

You might be able to squeeze a Channel Master 3021 (good) or 4228 (better) on your deck, and get better results with those, too.

blackngold19

11-29-04, 11:36 AM

Originally posted by sregener
A preamplifier might help. They come in two pieces - an indoor unit and an outdoor unit. The indoor unit plugs into the wall, preferably close to the television, and "injects" the power up the coax to the outdoor unit.

But preamplifiers won't help if multipath is the problem. Check your analog UHF signals for ghosting. If you see ghosts, more power isn't likely to fix your problem.

You might be able to squeeze a Channel Master 3021 (good) or 4228 (better) on your deck, and get better results with those, too.

Thanks, but I think those antennas are "eye sores" Appreciate the response though.:D

STT

11-29-04, 01:41 PM

on a standard VHF\UHF antenna what is the correct direction to point the antenna for VHF reception ? ; for UHF reception.

The response I receive is that the antenna works best in UHF mode with the Corner reflector pointing forward. For VHF stations it works better in the opposite position with the large elements in a swept back position.

Does this seem to agree with common thinking

DLGlos

11-29-04, 02:17 PM

First post here, so be a bit gentle.

Just bought our first HDTV, a Sony 36xs955, and I'm looking forward to seeing what can be picked up over the airwaves. We don't do cable or satelite, so that won't be a complication.

We live in urban Cincinnati, and according to the antennaweb.org site, almost every station I'm interested in transmits within a 3-10 mile radius from our house. They also happen to be roughly divided into two groups; one towards the NW and a second to the SW. There is an additional station WPTO in Oxford, roughly 30 miles to the north that would be nice to pickup, although I suspect they don't have much transmitter power and it would be a longshot.

My initial thought was to use two of the Winegard unamplified squareshooters, one aimed to the NW and second to the SW, and combine them with a diplexer of backwards splitter, although, from what I've read on this thread, that isn't a great idea. A pair of DB2's would also seem to do the trick, at less cost. The thought was simply two antennas might be less than one plus the rotator, plus the stream could be split into 2-3 rooms/TV's, where adjusting the rotator might help one set, but kill the signal on one of the others. Depending on how everything works, I might have to add a VHF element to pick up some of the old NTSC feeds, or the one ATSC feed that is at channel 10 (WCPO)?

The next set of questions involve the antennasdirect DB line. The DB2 and DB8 are listed as directional, which jibes with the CM4228. However, the DB4 is listed as multidirectional. What is up with that? Could the DB4 serve my needs? The price certainly seems OK. AD doesn't seem to have any polar plots indicating gain pattern, so I'm not comfortable just blindly ordering.

Finally, till this point, we have always used inside antennas, which for the most part, work OK. Although, there is a lot of mult-path around our area, and since I live in an old, urban neighborhood. there are many 50ft plus trees, and I'm closely surrounded by 3-story houses, like mine. It will not be that big of deal to mount a J-mast on the rear (west facing) fasciaboard of the house, although the cable run will be in the 75-100ft range. From what I understand, RG6 is the cable to use?

If anyone wants the antennaweb.org numbers, I can post them, or punch in 45208 as the zip.

Any advice is greatly appreciated.

Dave Glos

blackngold19

11-29-04, 02:23 PM

Originally posted by sregener
A preamplifier might help. They come in two pieces - an indoor unit and an outdoor unit. The indoor unit plugs into the wall, preferably close to the television, and "injects" the power up the coax to the outdoor unit.

But preamplifiers won't help if multipath is the problem. Check your analog UHF signals for ghosting. If you see ghosts, more power isn't likely to fix your problem.

You might be able to squeeze a Channel Master 3021 (good) or 4228 (better) on your deck, and get better results with those, too.

Both of these antennas are 40" high. I have ordered the antennas direct db4 which should have comparable gain to either of those 2 Channelmaster Antennas at 29X19 vs. 40x20 or 40X40. If the DB4 gains more than my Square Shooter I will gain an extra $80.00. I've got my fingers crosssed. Thx for the advice again.

cpcat

11-29-04, 03:30 PM

on a standard VHF\UHF antenna what is the correct direction to point the antenna for VHF reception ? ; for UHF reception.

If you have a true combo vhf/uhf antenna, it should do best pointed at the transmitter for both. If there are elements of the antenna *behind* the corner reflector, it's a combo. If not, you have a uhf-only antenna in which case vhf high band reception (7-13) may be better through the back end.

Low band (2-6) in a uhf-only as above is actually better broad-sided, i.e. 90 degrees off-axis or thereabouts. Neither position will give you reception as good as a vhf antenna, though, and the low band will suffer the most.

sregener

11-29-04, 03:39 PM

Originally posted by DLGlos
The next set of questions involve the antennasdirect DB line. The DB2 and DB8 are listed as directional, which jibes with the CM4228. However, the DB4 is listed as multidirectional. What is up with that? Could the DB4 serve my needs? [...]From what I understand, RG6 is the cable to use?

The DB4 is not "multidirectional." That's a mistake on their website. However, a DB4 (or CM3021) does have a pretty wide acceptance angle, close to 60 degrees. If all you're after are the Cincinnati stations, any 4-bay bowtie should work just fine. You may need to experiment to find a direction that works best.

Hooking up two antennas and pointing them in different directions and then combining them is highly unlikely to work in your situation, unless you invest in expensive filters. You could invest in a Radio Shack A/B RF switch that would let you switch between two antennas fairly easily, but that requires two coax runs to the switch.

Nitewatchman

11-29-04, 05:01 PM

Originally posted by DLGlos
There is an additional station WPTO in Oxford, roughly 30 miles to the north that would be nice to pickup, although I suspect they don't have much transmitter power and it would be a longshot.

WPTO digital is currently at full licensed power(400KW ERP) from WXIX(Fox) tower in Cincinnati. They do not currently transmit from Oxford as is the case with the analog station. The antennaweb info is incorrect on this. See Cincinnati thread(info on the stations can be found in the first few posts) and/or FCC info ( http://www.fcc.gov/mb/video/tvq.html ) for more details.

BTW, In addition to the Cincinnati stations, you are also well within the coverage areas of most of the Dayton digital stations, all of which are UHF currently. Dayton Towers are approx. 42~44 Miles NNE of Cincinnati Towers, and would be roughly the same distance NNE Of your location. Also, WKOI analog/digital(TBN) is located near Oxford, not their Community of license, Richmond, In. WKOI-DT is currently low power, with a directional transmitting antenna pattern which just about favors only their COL, Richmond, IN some 30 miles NNW of their tower.

Originally posted by DLGlos
I might have to add a VHF element to pick up some of the old NTSC feeds, or the one ATSC feed that is at channel 10 (WCPO)?

At your distance, if you don't have any serious terrain issues chances are good that you'll get a strong enough signal from WCPO-DT that a UHF antenna(or even a "coathanger" or short piece of wire hooked to back of TV) May do fine. For good quality analog VHF reception however,(especially for WLWT 5, or WDTN 2 Dayton/WHIO 7 Dayton/WAVE 3 Lousiville), you'll likely want VHF reception capability, even though you are close enough it is possible you might even get a decent pic from WLWT 5 with a UHF antenna.

----------------------------

If you don't want to use a rotor, for say Cincinnati/Dayton stations in different directions, the seperate antennas and A/B switch(s)+seperate coax feeds as Srenger mentioned is the way to go in this circumstance. Although I have a rotor as well(which I don't need for Cincinnati or Dayton stations) on one of my antennas, It works very well here from about 5 miles North of Middletown, FWIW. I feed both antenna feeds to TV's and other "devices" in two seperate rooms, and TV's in 4 seperate rooms from the Dayton antenna.

Simply combining 2 antennas(aimed in different directions) together onto the same feedline is going to put the antennas out of phase+induce multipath difficulties, basically because the antenna that is aimed in the "wrong" direction is going to pick up a likely multipath laden signal from any given station "off the side ...." It's not much different than having what we call a "random wire" antenna, which is exactly what it sounds like.

You can of course, combine seperate VHF/UHF antennas onto the same feedline, with the use of a VHF/UHF joiner such as CM #0549.

Looking at antennaweb info for your zip code however, I notice that you must be a few miles East of Mt Adams+Downtown - Which spreads out the Cincinnati towers quite a bit :

WCVN-DT (KET - Tower near I-275 in Taylor mill KY) is shown at 213 degree bearing.

Most of the Cincinnati towers, which are within a mile or two of downtown(WLWT/WCET, WXIX/WPTO-DT, WCPO/WBQC/WOTH+WKRC) towers are shown at 254~266 degree bearing.

WSTR-DT (WB HD) is shown at 318 degree bearing, that's the "star tower" just West of 75 in Finneytown. Currently, unfortunetly they are at low power, and their directional antenna pattern/relative field values as shown on FCC site only indicates they are squirting only about 600 watts ERP in your direction. TBN LP translator, W61DE (analog) also currently transmits from near WSTR tower location.

So, That's a a difference of over 100 degrees for all the Cincinnati stations - Hopefully you'll be able to use one heading "in the middle" to aim at the "main" towers in the middle+still get enough of a "good" signal from WSTR/WCVN off the sides, so a 4 bay UHF bowtie antenna would probably be a good choice in this circumstance -- Still, reception of WSTR-DT especially may prove difficult with such "off target" antenna aiming from your location.

Hope this helps+let us know how it goes.

DLGlos

11-29-04, 05:06 PM

The DB4 is not "multidirectional." That's a mistake on their website. However, a DB4 (or CM3021) does have a pretty wide acceptance angle, close to 60 degrees. If all you're after are the Cincinnati stations, any 4-bay bowtie should work just fine. You may need to experiment to find a direction that works best.

sregener

Thanks for that info. Like the price of the CM3021 too. Rats on the combining antennas issue though. A pair of the CM3021's would be less than adding a rotator. I'm figuring I might have to add a rotator as the two main directions to the transmitter clusters are roughly 90-100 degrees apart.

If I have to go with a rotator, should I perhaps consider a more directional Yagi type antenna (CM3022?)? Perhaps even one of the VHF/UHF combos might even be OK since signal strength won't likely be an issue?

I have a feeling multipath, and possibly a strong local FM station, might be my biggest issues. Of course, that is just theory till I get the actual TV and try.

Will also try the Cincinnati reception thread to see what some of those folks say.

Again, thanks.

David Glos

Nitewatchman

11-29-04, 08:42 PM

Originally posted by DLGlos

If I have to go with a rotator, should I perhaps consider a more directional Yagi type antenna (CM3022?)? Perhaps even one of the VHF/UHF combos might even be OK since signal strength won't likely be an issue?

Well, for Cincinnati stations, and overall, a small~medium size VHF/UHF combo with rotor wouldn't necessarily be a bad idea, especially if you want good reception for the VHF analogs in the area. And, it should be pretty easy + inexpensive to change antennas later on, if you wish. However : #1). You still might be doing a lot less "rotoring" with a 4bay bowtie. #2). if you are looking for reception from say, the Dayton PBS digital station(which is on hi-UHF channel 58), the "extra" performance from a dedicated, hi-gain, directional UHF antenna such as a CM4248 Yagi, or CM4228 8-bay bowtie may be worthwhile.

So, you probably have a lot of options to consider, which Is partly why I provided more info for you on the stations in the area farther below. Given your proximity to strong Cincinnati TV/FM stations, A preamp is probably not a good idea, as I would imagine it is likely to have overload/intermod issues from the strong local signals.

Originally posted by DLGlos
the two main directions to the transmitter clusters are roughly 90-100 degrees apart.

Close, but not exactly.

So, this will probably be much more than you wanted to know but hopefully some of the below helps you out :

As I noted in my last post, of the Cincinnati stations, MOST of the Cincinnati stations are within a 10 degree heading or so from your location. The Following info is based on "center" of 45208 zip code, your exact location may vary a bit -- headings are adjusted for magnetic deviation(about +5.2 degrees from the true bearing) :

WKRC-DT 31 (analog 12) - CBS HD - 3.9 Miles at 254 deg.
WCPO-DT 10 (analog 9) - ABC HD - 3.5 miles at 263 deg.
WQBC-CA 25 ANALOG ONLY Currently - UPN - 3.5 miles at 263 deg.
WOTH-LP 38 ANALOG ONLY currently - IND - 3.5 miles at 263 deg.
WLWT-DT 35 (analog 5) NBC HD - 4.7 miles at 265 deg.
WCET-DT 34 (analog 48) PBS HD - 4.7 miles at 265 deg.
WXIX-DT 29(analog 19) - Fox HD - 6.2 miles At 266 deg.
WPTO-DT 28 - PBS HD - 6.2 miles at 266 deg.

WCPO/DT+WQBC+WOTH are on the same tower. WLWT/DT+WCET/DT are on the same tower. WXIX/DT+WPTO-DT are on the same tower.

WBQC-CA 25(UPN) is increasing analog power+ moving to Channel 38 around first of year, WOTH-LP is moving to 25+using WBQC's current facilities. Note that WOTH-LP was originally on channel 35, but was displaced by WLWT-DT. They moved to 39 first, but were displaced by WKOI-DT 39.

WCET-DT offers PBS HD channel nightly from 7pm~11pm+2 SD multicast services(simulcast of analog+PBS kids), at other times they offer 4 multicast SD services. WPTO-DT offers time shifted PBS HD programming only on Sat/sun nights 6pm~11pm, at all other times it is 4 channel SD multicast. WCPO-DT offers a multicast 24/7 local weather channel in addition to it's ABC HD+simulcast of analog 9(What isn't available in HD is upconverted to 720p - the other stations in the area also "simulcast" their analog station in this manner.

-----------------------------------------------------

THESE THREE Cincinnati OTA stations are the ones that are at significantly different bearings from your location:

WCVN-DT 24 (analog 54) - PBS HD/KET - 8.2 miles at 213 degrees
WSTR-DT 33 (analog 64) - WB HD - 6.5 miles at 318 degrees - *
W61DE 61 - ANALOG ONLY - TBN translator - 6.3 miles at 327 degrees.

WCVN-DT/KET offers PBS HD channel Mon-Sat 8pm-11pm nightly, Sun 7pm-11pm - It's plus 2 SD services - Simulcast of analog KET1 and KET2, the latter which is simulcast of WKMJ 68, Louisville, KY.

* - As noted in earlier post, WSTR-DT's transmitting antenna for their current low power digital operation does not favor the East/SE. They are currently squirting only about 600 watts ERP in your direction, according to technical info available on FCC site -- Which is probably receivable from your distance given a good, outdoor antenna setup+"on target" antenna aiming. However, there is also the additional factor of WCET-DT 34 operation on 1st adjacent channel 34 squirting about 215KW ERP in your direction, and it may be difficult for your receiver to be selective enough to "see" enough "good" signal on 33 from WSTR-DT for good results. While 1st adjacent channel digital stations can work quite well, it's best if they are co-located(which WCET/WSTR are not - they're several miles apart), AND aren't running "too much different" power levels -- For the most part, in most directions it's fine since WSTR-DT is sending out as much as 17.1KW ERP in most directions, the current potential exception being towards the East+SE of their tower. I don't believe I've heard any reports from your general area which have indicated good reception of WSTR-DT.

--------------------------------------------------------------------------------

Other stations for which you are within the coverage area :

Oxford area:

WPTO 14 (analog) PBS Oxford - 30.3 miles At 333 degrees
WKOI 43 (analog) TBN - Tower near Oxford - approx 30 miles to your NNW - You are probably outside of the digital station(ch 39) coverage area currently due to their low power+directional antenna pattern, although the "back lobe" of the pattern does favor your direction, so if you are at all interested in this station you might have some luck. WKOI-DT is currently the only DTV station out of 15 in the area which does NOT offer HD.

Owenton KY:

WKON-DT 44(analog 52) - PBS/KET - 46.8 miles at 210 degrees - same KET statewide(KY) services as is provided from WCVN/WCVN-DT.

Louisville, KY:

WAVE 3 (analog) - NBC - 71 miles at 234 degrees. You are outside of their digital station(ch 47) coverage area, which transmits from a different, more distant location from Cincinnati. You are within WAVE 3's HUGE coverage area for a number of reasons -- Their HUGE tower(the tallest structure around these parts), and because of their hi-power lo-VHF channel 3 allocation.

Dayton, Ohio Area:

WDTN-DT 50(analog 2) - NBC HD - 41.2 miles at 18 degrees.
WHIO-DT 41 (analog 7) - CBS HD - 42.5 miles at 18 degrees.
WPTD-DT 58 (analog 16) - PBS HD - 41.6 miles at 18 degrees.
WKEF-DT 51 (analog 22) - ABC HD - 41.4 miles at 18 degrees
WBDT-DT 18 (analog 26) - WB HD - 41.8 miles at 18 degrees - *
WRGT-DT 30 (analog 45) - FOX HD - 41.8 miles at 18 degrees - *

WPTD-DT runs PBS HD Channel 6pm~6am nightly+2 SD services. from 6am~6pm, they are in 4 channel multicasting mode.

* - note - These two digital stations may be particularly difficult to achieve good reception results from your location due to first adjacent channel issues with Cincinnati stations, as well as power/directional transmitting antenna issues. For these stations especially, the more directional your antenna -- the more it "rejects" a good amount of signal from the adjacent channel "blow torch" Cincinnati stations off the side, the better chance you have at receiving them.

For more info on the SD multicast services offered by the local PBS stations, see the associated websites.

rashby

11-30-04, 02:18 AM

I just received a dish 921 receiver and trying to get ota hdtv with it. I am able to get a couple of stations but not consistent. I'm 70 miles south of evansville,In and 75 miles north of Nashville. I'm on top of a small hill with a 40ft tower with a radio shack uhf/vhf combo ant. and cm amp. From what I've read I'd be better off with a split system. My question is would I be better off with a yagi or the bow type and or double stacked yagi. right now I'm leaning towards either the cm4248, ac mxu59 or the 91xg. Has any one had any experience with one of these antennas at this type of distance. any help would be appreciated. Happy Holidays. Rodney

cpcat

11-30-04, 07:56 AM

I'd say you're best option would be the XG91 with CM 7775 or 7777 preamp and a CM 9251 rotor. The XG91 is generally felt to be an equivalent to antennas such as Televes, Blake, Funke, Triax available from the U.K. I wouldn't go with an 8-bay because of unacceptable wind load on your tower/rotor as well as the fact that with a Yagi/corner reflector you have the option of stacking later.

All of your digitals (BG and Paducah) are uhf,
except for NBC from Nashville on 10. You'd have a good shot at 10 with an antennacraft Y10 7-13 mounted below (at least 60 inches) your XG 91. In this case, you'll need the CM 7777 for separate uhf and vhf inputs. Winegard also makes a similar high band antenna.

For an even better high band antenna, see http://community-2.webtv.net/GregBarker/UltraHighGain/index.html

If you need more for uhf, you could always stack later, but that's a job on a 40 foot tower.

Go to http://www.2150.com/broadcast/default.asp and punch in your exact coordinates in decimal form for bearings to the towers. You'll need them for precise aiming.

sregener

11-30-04, 10:03 AM

Originally posted by rashby
right now I'm leaning towards either the cm4248, ac mxu59 or the 91xg. Has any one had any experience with one of these antennas at this type of distance. any help would be appreciated.

The 4248 is an underperformer, in my opinion. I had a stack of two and it didn't match my Winegard 7084P for performance on UHF. I now use the 91XG and it works very well for me, although 70+ miles over rough terrain isn't easy and I don't get everything consistently.

From what I've read, either the antennasdirect 91XG or the DB8 would be a good choice to maximize your reception. Some believe the bowties are better when you don't have line-of-sight.

goldrich

11-30-04, 12:10 PM

Originally posted by cpcat
I'd say you're best option would be the XG91 with CM 7775 or 7777 preamp and a CM 9251 rotor. The XG91 is generally felt to be an equivalent to antennas such as Televes, Blake, Funke, Triax available from the U.K. I wouldn't go with an 8-bay because of unacceptable wind load on your tower/rotor as well as the fact that with a Yagi/corner reflector you have the option of stacking later.

I, too, would place the XG91 on a recommended list. I bought one a few months ago and performed some comparison tests between it and the CM 4221 (4-bay) and the CM 4228 (8-bay). The winner among these 3 antennas was the XG91.

I then conducted some comparisons between the XG91 and my permanent setup, two Triax Unix 100's in a horizontal stack. Because UHF signals can have so many hot and cold spots, it is really hard to judge one antenna against another one, even when the two antennas are at the same height and just a few feet apart. With this in mind and using a CM 7775/7777 on each setup, results were somewhat mixed. Some distant analog and digital stations (60 to 115 miles) were better with the Triax stack while some were actually better with the single XG91. From my location, Cincinnati stations (100 miles) were better with the Triax stack, while several times, along with some tropospheric assistance, Louisville stations (110 miles), especially digital, were better with the XG91. As a single antenna, the XG91 seems to work quite well.

Steve

rashby

11-30-04, 01:33 PM

sounds like the xg91 is the way to go. Has any one tried a horizontal or vertical stack with the xg91 or would this be a overkill. Rodney

tbb1226

11-30-04, 02:39 PM

Now, what do I do? :(

For reference, see my earlier issue in Post#367 (http://www.avsforum.com/avs-vb/showthread.php?postid=4463601#post4463601)

Current status: I managed to find a good position and direction (back to ~265º) to point the 4221 on top of the 10 foot mast and get all the stations I want with solid strength in good weather. I thought I had it licked, then had some problems during the next rainstorm. I noticed that it was moving quite a bit with the wind, and figured that wasn't helping matters. So, I added some guy wires, and now it's fairly wind resistant.

Problem now is that WXYZ-DT (channel 41 at 6.2 miles) has occasional audio dropouts and freezing video. It will look and sound fine for long periods of time (sometimes 20-30 minutes, sometimes several hours), then start hiccuping for a stretch, then be alright, and so on. When I check signal strength (HD-TiVo), it's always solidly above 80, but fluctuating with a range from, say 85 - 92. At no time do I get an indication that the signal is dropped. Adding an attenuator merely shifts the mean lower, keeping pretty much the same standard deviation. Same result when I turn the antenna further south.

I don't think I can move the mast, since this is such an intermittent problem, I don't know how I'd judge whether one spot is better than another. My only other thought is to remove the diplexers from the mix and run a straight antenna cable, but I don't know that diplexing would cause this kind of problem. Any other suggestions?

sregener

11-30-04, 02:55 PM

Originally posted by tbb1226
My only other thought is to remove the diplexers from the mix and run a straight antenna cable, but I don't know that diplexing would cause this kind of problem.

That's probably your best choice. Diplexers are known to cause reception problems, and sometimes those problems aren't consistent.

Also check your weatherproofing on all your outdoor connections. Water on the connectors can cause problems.

cpcat

11-30-04, 03:38 PM

Has any one tried a horizontal or vertical stack with the xg91 or would this be a overkill. Rodney

It wouldn't be overkill at your distance, but it might not be necessary. I'd try a single first if I were you. You're in fairly flat terrain out there and at 40 ft it may just do o.k. Like I said, you can always upgrade later if you desire. Horizontal stacking works better for digital reception in my experience, but I'm in hilly/mountainous terrain and multipath may be more of a problem for me than it would be for you (horizontal stacking deals with multipath by narrowing horizontal beamwidth).

tbb1226

11-30-04, 05:25 PM

Originally posted by sregener
That's probably your best choice. Diplexers are known to cause reception problems, and sometimes those problems aren't consistent.I was afraid you'd say that. It won't be that hard to do, but I don't like the feeling of poking yet another hole through my masonry. Not to mention adding another coax to the pile of cables behind my entertainment center......

Thanks, again, for taking the time to offer your advice.

dswallow

11-30-04, 09:00 PM

Originally posted by tbb1226
Now, what do I do? :(

For reference, see my earlier issue in Post#367 (http://www.avsforum.com/avs-vb/showthread.php?postid=4463601#post4463601)

Current status: I managed to find a good position and direction (back to ~265º) to point the 4221 on top of the 10 foot mast and get all the stations I want with solid strength in good weather. I thought I had it licked, then had some problems during the next rainstorm. I noticed that it was moving quite a bit with the wind, and figured that wasn't helping matters. So, I added some guy wires, and now it's fairly wind resistant.

Problem now is that WXYZ-DT (channel 41 at 6.2 miles) has occasional audio dropouts and freezing video. It will look and sound fine for long periods of time (sometimes 20-30 minutes, sometimes several hours), then start hiccuping for a stretch, then be alright, and so on. When I check signal strength (HD-TiVo), it's always solidly above 80, but fluctuating with a range from, say 85 - 92. At no time do I get an indication that the signal is dropped. Adding an attenuator merely shifts the mean lower, keeping pretty much the same standard deviation. Same result when I turn the antenna further south.

I don't think I can move the mast, since this is such an intermittent problem, I don't know how I'd judge whether one spot is better than another. My only other thought is to remove the diplexers from the mix and run a straight antenna cable, but I don't know that diplexing would cause this kind of problem. Any other suggestions?
Have you tried reaiming during such a rainstorm? My guess is somewhere nearby the rain is ultimately leading to some intermittent reflections of the signal giving you multipath issues.

Diplexers might result in a slight signal loss (very slight), but shouldn't be a cause of this sort of behavior.

hew2nd

11-30-04, 09:34 PM

According to Antennaweb.org I'm about 50 miles from the antennas. I have just purchased (but not yet received) a Mitsibushi Diamond 65" HDTV. I'm wondering if aZenith Silver Sensor Digital Antenna will work. (This would help me save the ridicuolus $50 charge Comcast charges for delivering the set top box.) Besides, I've got the tuner in the TV so I might as well use it if I can.
Thanks
Harry

tbb1226

11-30-04, 09:58 PM

My current issue seems to be independent of weather. In fact, I'm not even sure that it's reception-related. Two subchannels on the same frequency (weather radar and ABCNewsNow) are not exhibiting these dropout symptoms at all. Some cable subscribers in the area have started reporting similar problems with their WXYZ-HD audio and video, too. I don't know what might be causing it, but I'm not convinced it's an antenna problem anymore. :confused:

If I figure it out, I'll post back here. Thanks, again.

Jon_Patrick

11-30-04, 10:01 PM

Here is my antena web info, i have over 80% reception on 8, 17, 41 but i cant even get an image on 3. Any suggestions

http://www.antennaweb.org/aw/Address.aspx

Jon_Patrick

11-30-04, 10:18 PM

sorry, try 49007 in zip code

Jon_Patrick

11-30-04, 10:42 PM

ok i am using a medium multi directional antena, what if i bump up to a large directional antenna with a line amplifier, while i see a big difference in reception?

tbb1226

11-30-04, 11:42 PM

Your "channel 3" is actually broadcast on channel 2 (low VHF), while all the rest of your local digitals are either UHF or high VHF. Going directional should help, but make sure you also look at frequency response of the antenna, and get a combo that has good gain in all bands.

jimc705

12-01-04, 12:39 AM

hew
Don't think an indoor antenna is going to do a good job at that distance. Make sure you can return it if it doesn't work. Here's the best indoor UHF available from Radio Shack special order or ebay at this link.
http://cgi.*********/ws/eBayISAPI.dll?ViewItem&category=73383&item=5734755989&rd=1
You probably need an outdoor UHF antenna for reliable reception at 50 miles. For $50 you can get an excellent outdoor antenna if you mount it yourself.

cpcat

12-01-04, 01:43 AM

ok i am using a medium multi directional antena, what if i bump up to a large directional antenna with a line amplifier, while i see a big difference in reception?

You may not need the amplifier at that distance. You need at least a medium directional and a large directional would be safer. An option would be a vhf/uhf combo such as the CM 3016 :http://www.channelmaster.com/home.htm with a CM 9251 rotator.
Here's a link to gain figures from CM on their Advantage antennas:
http://www.starkelectronic.com/cmg4.htm

They both should be available at Lowe's.

Multidirectional antennas just don't work that well.

grouper

12-01-04, 07:42 AM

wondering if anyone in here has used the winegard ss2000, and how the vhf performance is. I'm 40 miles from the towers. or is there a better all around antenna
thanks

sregener

12-01-04, 09:42 AM

Originally posted by grouper
wondering if anyone in here has used the winegard ss2000, and how the vhf performance is. I'm 40 miles from the towers. or is there a better all around antenna

At 40 miles, if you need both VHF and UHF reception, you should get a medium-to-large VHF/UHF combo antenna, not a fancy little box, even one as fancy as the Winegard SS2000. Probably the SS2000 would work okay on high-VHF (channels 7-13) though not great, and it would work poorly or not at all on channels 2-6.

goldrich

12-01-04, 09:44 AM

Originally posted by grouper
wondering if anyone in here has used the winegard ss2000, and how the vhf performance is. I'm 40 miles from the towers. or is there a better all around antenna
thanks

Your location is_________? It is much easier for members to pass along recommendations when they can assess your particular stations, terrain, etc. Thanks.

Steve

blackngold19

12-01-04, 11:16 AM

Originally posted by hew2nd
According to Antennaweb.org I'm about 50 miles from the antennas. I have just purchased (but not yet received) a Mitsibushi Diamond 65" HDTV. I'm wondering if aZenith Silver Sensor Digital Antenna will work. (This would help me save the ridicuolus $50 charge Comcast charges for delivering the set top box.) Besides, I've got the tuner in the TV so I might as well use it if I can.
Thanks
Harry

Good luck with the Silver Sensor at 50 mi. I used it at 35 mi and got CBS at around 70% and ABC in the mid 60's. You have to get outside for best results.

blackngold19

12-01-04, 11:17 AM

Originally posted by grouper
wondering if anyone in here has used the winegard ss2000, and how the vhf performance is. I'm 40 miles from the towers. or is there a better all around antenna
thanks

I am currently using the SS, but I don't think I have any available VHF digital channels from my tower. All I can say is that it works fairly well on UHF for its size at 35 miles.

darimont

12-01-04, 12:00 PM

Sorry, but I posted this by itself then found that it belongs here I think.

Samsung 360 overdriving with antenna?

I live in Aurora Illinois about 45 miles from Chicago and have a 40 ft tower with a winegard, I forget what model, but its the next down form there biggest with a winegard preamp mounted on the mast. It seems that if I unplug the preamp that the signal goes up for all the dt channels, but I loose 2.1. With the amp plugged in channel 2.1 is about 70 %, but the others are at 50 %. With out the amp the others go to 90% but I then loose 2.1. My question is, could I be over driving the 360's tuner and the tuner is clamping the other channels? Does anyone have any ideas? With the amp plugged in the other channels are stable. Will over driving the tuner hurt anything?

Just found the numbers, Antenna HD7084p , (edited) Amp ap-8700 I had the wrong amp #

Thanks
Dan

sregener

12-01-04, 12:38 PM

Originally posted by darimont
Will over driving the tuner hurt anything?

Just your reception.

Sounds like you should replace the amp you have with a AP-3700.

goldrich

12-01-04, 12:44 PM

Originally posted by darimont
Sorry, but I posted this by itself then found that it belongs here I think.

Samsung 360 overdriving with antenna?

I live in Aurora Illinois about 45 miles from Chicago and have a 40 ft tower with a winegard, I forget what model, but its the next down form there biggest with a winegard preamp mounted on the mast. It seems that if I unplug the preamp that the signal goes up for all the dt channels, but I loose 2.1. With the amp plugged in channel 2.1 is about 70 %, but the others are at 50 %. With out the amp the others go to 90% but I then loose 2.1. My question is, could I be over driving the 360's tuner and the tuner is clamping the other channels? Does anyone have any ideas? With the amp plugged in the other channels are stable. Will over driving the tuner hurt anything?

Just found the numbers, Antenna HD7084p , Amp ap-2880

Thanks
Dan

Dan,

Your situation sounds very much like the one I used to experience with a couple of stations in my area. Some STB's have small built-in signal amplifiers, so when you add the amplification from the preamp it can be a little too much for the receiver, or at least I found this to be true. I had one station that would actually register "0" (zero) signal strength on the meter when the preamped signal was full-strength. Then I added a RS variable attenuator to the incoming cable. When I reduced the signal just a little, the signal strength meter shot up and I had a great, stable signal level. I'm using the RCA DTC-100 and the LG LST-3100A, and my preamp is the CM 7775.

This might help you out. My 2 cents.

Steve

darimont

12-01-04, 02:03 PM

Thanks for the replies guys.

goldrich,
I may try what you said about the RS variable attenuator first, before spending another $60 bucks on different amp. If I can reach some kind of balance between the 2.

sregener,
I looked up the 3700 and I think I may give that a try, as I see it only amps VHF. 2.1 is vhf and the rest of mine are up in uhf range. I may try taking it out as I know when you just unplug it you loose more the if you take it out. Is there a way to just attenuate UHF? I don't like going up the tower unless I have to.

I just wanted to make sure i wasn't going to fry my tuner until i can get this corrected.

Dan

cmassa

12-02-04, 12:40 AM

I've recently purchased a Sony 55XS955 and am extremely happy with it but I need to do something about my antenna, currently a Terk TV50 in my attic (I know, I know). Here are my results for digital stations from antennaweb.org (zip 95973)

KHSL-DT 43.1 CBS CHICO CA 30° 14.1 43
KNVN-DT 36.1 NBC CHICO CA 326° 32.1 36
KCVU-DT 30.1 FOX PARADISE CA 29° 14.6 20
KRCR-DT 34.1 ABC REDDING CA 308° 67.0 34
KIXE-DT 9.1 PBS REDDING CA 308° 67.0 18

I currently get the NBC digital station quite well. Most of the time the CBS digital station has lots of ghost images and I watch the analog channel (12) which also has a few faint ghosts. Funny, when the analog station has bad ghosting, the digital channel is clear. I was getting the FOX digital station well but it is now gone after moving the antenna around some (It is back in its original location and orientation.) I have received the digital PBS for only a few seconds once. I have not gotten the ABC station at all. The analog ABC and PBS stations (7 and 9) are quite snowy as is my UPN station (22 - analog only). Most of the digital stations are just converting their analog channel but TitanTV lists ABC as broadcasting HDTV which I would really like to get. I don't know what power level it is broadcasting and it is 67 miles away. Sacramento stations are a bit far, probably at least 90 miles or more.

I would like to keep the install simple. Inside the attic would be best. I would prefer not to use a rotor (if possible) to keep use of the system easy for the family. I don't think my wife would like changing the antenna direction every time we changed channel. Would something like a DB8 from antennasdirect work? I have a first floor attic over my garage and a second floor attic over the house to use, both have RG6 cables in them. Would I need an amp/preamp? If mounted outside, I would want to keep it low to the roof for asthetics.

Thanks for any recommendations.

Chris

MAX HD

12-02-04, 02:37 AM

cpcat

12-02-04, 07:20 AM

cmassa,

Your only chance for ABC is outside with the best possible antenna setup for distance. It's likely only at 26 kw and with an eventual "full power" of 166kw. I can't tell whether you're in the 41dbu service window because you didn't post your location, but most likely not.

The DB8 outside on a rotor with a preamp such as CM 777x series would be a start, but 26 kw at 67 miles will require some very favorable topography.

See http://www.fcc.gov/fcc-bin/tvq?call=KRCR for the info on that ABC station.

darimont

12-02-04, 08:36 AM

Originally posted by darimont
Thanks for the replies guys.

goldrich,
I may try what you said about the RS variable attenuator first, before spending another $60 bucks on different amp. If I can reach some kind of balance between the 2.

sregener,
I looked up the 3700 and I think I may give that a try, as I see it only amps VHF. 2.1 is vhf and the rest of mine are up in uhf range. I may try taking it out as I know when you just unplug it you loose more the if you take it out. Is there a way to just attenuate UHF? I don't like going up the tower unless I have to.

I just wanted to make sure i wasn't going to fry my tuner until i can get this corrected.

Dan

goldrich and sregener,

I tried the RS attenuator last night and it worked. I have it turned all the way up and even 2.1 is good. I had the wrong number for the amp, its a ap-8700 which is 17db for VHF and 19 for uhf, with the antenuator all the way up its a 20db cut, so this tells me I don't need the amp. I must have been losing alot buy just unplugging the power supply for the preamp, at this point it lookes like I'll be taking the amp out when I feel like going back up the tower.

Thanks Again
Dan

cmassa

12-02-04, 10:01 AM

cpcat,

Thanks for the info. I am located on the north side of Chico. At 26 kw I am outside their service window. At the eventual 166 kw I am inside the service window. The terrain around here is flat. Redding is at the north end of the Sacramento Valley in the foothills. My elevation here is about 150 ft. The transmitters are are at 1900 ft on top of a hill (small mountain?) and about 1000 ft above the average terrain. So at 26 kw, being outside the service window, is it even possible to receive? If I eliminated the Redding digital stations, would a DB8 clear up my reception of other stations?

Chris

Originally posted by cpcat
cmassa,

Your only chance for ABC is outside with the best possible antenna setup for distance. It's likely only at 26 kw and with an eventual "full power" of 166kw. I can't tell whether you're in the 41dbu service window because you didn't post your location, but most likely not.

The DB8 outside on a rotor with a preamp such as CM 777x series would be a start, but 26 kw at 67 miles will require some very favorable topography.

See http://www.fcc.gov/fcc-bin/tvq?call=KRCR for the info on that ABC station.

DavoM

12-02-04, 11:11 AM

Hey Guys,

I'm in Lehigh Acres, Florida and I am trying to receive UPN programming on from a station in a neighboring community, WTVX in Fort Peirce. We have a real problem with our UPN affiliates in my area and I'm a big Enterprise fan. I'd love to see this show in HD.

For those of you technically inclined I'm wanting to know what it will take to get this channel.

If I've done the math right, it looks like I'm barely over 100 miles from WTVX's transmitter, their tower's height is about 1500 feet, my house's elevation is about 20 feet, and my compass orientation is about 54 degrees. I already have a large directional antenna in the attic pointing the other way picking up the locals from my area, but I'd like to get WTVX as well.

I've looked at the FCC's website and if I'm reading this correctly, it looks like their analog channel has an ERP of 5000 kw, and the digital channel has an ERP of 704 kw. I'm trying to confirm if this is current information w/ the guys in the West Palm thread.

1. Given the wattage and distance I am from the tower, is is this even possible? Is there any other option besides a large roof mounted directional antenna?

2. How does one go about using two separate antennas on a receiver like my HDTivo? Do I need a combiner / splitter? Will I need an amp too?

3. I've heard signals are easier to pick up at night. Is that correct and why?

Thanks in advance for the help.

Peace,

DM

cmassa

12-02-04, 12:43 PM

When installing a new rotor, does a control wire have to be run or can the signal run on the coax? If installing a rotor, running a new wire to my home theater will be very difficult. Could I use unused pairs in a Cat5 wire which is supplying telephone and is already in place?

Chris

squid90

12-02-04, 02:16 PM

New to the forum and wonder about experiences with nearby radio towers and interference with OTA reception. Haven't purchased an antenna yet, but antennaweb indicates a potential for reception of digital and analog stations.

The radio tower resides approximately 1 mile west of my home and primary local signals from KC are nearly 180 degrees opposite direction. I realize probable difference in frequency spectrum but defer to those more knowledgeable by experience or otherwise.

sregener

12-02-04, 02:52 PM

Originally posted by DavoM
1. Given the wattage and distance I am from the tower, is is this even possible? Is there any other option besides a large roof mounted directional antenna?

2. How does one go about using two separate antennas on a receiver like my HDTivo? Do I need a combiner / splitter? Will I need an amp too?

3. I've heard signals are easier to pick up at night. Is that correct and why?

1. Possible? Yes. Probable? No. Darn-near-impossible? Yup. But if you have really flat land between you and the broadcasting tower, are willing to get a very-large UHF antenna (think 8-9' long) and put it up as high as your local codes allow (probably between 50-70') you have a shot.

2. You'd use a Channel Master "Jointenna" for the channel number you're trying to get. It has two inputs and one output - one input for the specific channel number you want to receive, and one for everything else.

3. It's been my experience that nighttime reception is better than daytime. A large part of this is the sun's action on the troposphere, which is where all long-distance reception of UHF signals comes from.

I have a 54' tower, an AntennasDirect91XG, a 28db UHF preamp, and I get stations from as far away as 89 miles, on a good day. On a bad day, anything beyond 60 miles is iffy. My terrain is average (somewhat hilly) and my location is not very high.

sregener

12-02-04, 02:54 PM

Originally posted by cmassa
When installing a new rotor, does a control wire have to be run or can the signal run on the coax? If installing a rotor, running a new wire to my home theater will be very difficult. Could I use unused pairs in a Cat5 wire which is supplying telephone and is already in place?

A rotor control wire contains 3 leads. Phone wire can work in some cases, but if it gets very cold where you are, there may not be enough conductivity to get that power (12V) up there. Also, if you use the rotor while on the phone, the voltage could easily bleed over and disrupt your telephone conversation.

Coax only has two connections, so it can't be used to run a rotor.

jimc705

12-02-04, 03:07 PM

Davo,

Your talking a 100 miles is possible but highly unlikely to to the curveture of the earth. Here's a link to the coverage area for WTVX. If your in the coverage area you should get it fairly easy. Outside but still close to the line 50/50 chance. Way outside forget it.
http://www.fcc.gov/fcc-bin/FMTV-service-area?n=DT616115.html

At that distance you would need to probably stack UHF antenna with a amp. Considerable investment for one channel. Good Luck.

jimc705

12-02-04, 04:02 PM

enoree,
http://www.fcc.gov/fcc-bin/FMTV-service-area?n=DT595738.html
coverage map for char;otte fox. You're on the very edge of reception.

http://www.fcc.gov/fcc-bin/FMTV-service-area?n=DT618270.html
also very edge of reception.

If you ditch the rat shack amps and get a good cm 7777 and a cm 4228 or antennas direct xg91 I think you'll get Columbia. You can order the antennas direct xg 91 and return it if it doesn't work. Best gurantee of any antenna manufacturer. The rat shack amps have too much noise for very low signal level. The CM has 2.0 Rat Shack typically higher then 4 db and at UHF about 6 to 8 DB a lot of noise. You still may only get evening reception but I think it will lock and look good.
Scrape the rat shack preamps ant UHF antenna.

DavoM

12-02-04, 05:40 PM

Jim,

Thanks for the help.

Peace,

DM

cpcat

12-03-04, 12:14 AM

So at 26 kw, being outside the service window, is it even possible to receive? If I eliminated the Redding digital stations, would a DB8 clear up my reception of other stations?

Cmassa,
It's possible. Most likely you'll not get consistent reception until they go full power whatever you do, though. You should get more consistent reception on the closer stations anyway if you go outside. The DB8 probably is the best single broadband uhf option for distance. The disadvantage to an 8-bay is it acts like a sail and presents a fair amount of wind load to the rotor and mount. Another option would be a yagi/corner reflector such as the xg91. You'll give up some minimal gain below ch. 40 compared with the 8-bay but it's lighter and easier on the installation. You can also get another and stack them later if you need more antenna.

ticoar

12-03-04, 12:49 PM

Whats the best method for splitting the antenna signal to reach multiple tv's?

sregener

12-03-04, 01:11 PM

Originally posted by ticoar
Whats the best method for splitting the antenna signal to reach multiple tv's?

Get a low-loss splitter. The fewer splits, the better. Radio Shack has a nice $10 splitter that has 3.5db of loss (theretically close to the minimum loss possible.) They have a 3-way splitter that costs 4.5db of loss per connector, but mine caused too much loss on very-weak stations. If you have strong signals, any splitter will work fine. If you have weak ones, splitting a signal even once may cause problems.

Avoid amplified splitters unless nothing else works.

Pokelahoma

12-03-04, 04:00 PM

Ok, I am 19mi from the field of stations here in Tulsa, OK (74119) with a 40ft building in my line of sight, 100ft from my antenna on the roof. My equipment is an RCA DTC-210 D* box and an FM trap with 100ft of cable to my RCA 58” UHF/VHF antenna on the top of my roof. I have been able to get these results.

Chan Station Network Compass Dist Freq Tower Power My reception
8.1 KTUL-DT ABC 114° 23.9 10 1779 ft 7kw 80%
23.1 KOKI-DT FOX 109° 19.0 22 1312 ft 1,000kw 40%
11.1 KOED-DT PBS 109° 19.3 38 1299 ft 500 kw 70%
41.1 KTFO-DT UPN 109° 19.0 42 1250 ft 900 kw 0%
6.1 KOTV-DT CBS 109° 19.3 55 1609 ft 300 kw 80%
2.1 KJRH-DT NBC 109° 19.3 56 1657 ft 800 kw 80%

I tried an CM 7777 amp and it cuts out all my channels to 0%, I also tried a Radio Shack variable attenuator and that does nothing to most channels even if I turn it all the way up to max attenuation, but other than that does not affect the # of channels I get. My analog channels seem to have ghosting but I am not sure how to get rid of that (I have aimed the ant in every direction).

I hooked up a $10 bottom of the line UHF/VHF rabbit ear set and stuck it by my window and got these results…

Chan Station Network Compass Dist Freq Tower Power My reception
8.1 KTUL-DT ABC 114° 23.9 10 1779 ft 7kw 70%
23.1 KOKI-DT FOX 109° 19.0 22 1312 ft 1,000kw 80%
11.1 KOED-DT PBS 109° 19.3 38 1299 ft 500 kw 70%
41.1 KTFO-DT UPN 109° 19.0 42 1250 ft 900 kw 90%
6.1 KOTV-DT CBS 109° 19.3 55 1609 ft 300 kw 80%
2.1 KJRH-DT NBC 109° 19.3 56 1657 ft 800 kw 10%

So basically my rabbit ears are performing as well if not better than my tripod mounted, 20ft off the ground, 58” long boom, combo antenna.

I don’t want to have to haul out the rabbit ears every time I want to watch UPN or Fox. Man this project has been a nightmare. Any advice on what to do from the experts here?

-A very frustrated Pokelahoma :confused:

blackngold19

12-03-04, 05:39 PM

Originally posted by Pokelahoma
Ok, I am 19mi from the field of stations here in Tulsa, OK (74119) with a 40ft building in my line of sight, 100ft from my antenna on the roof. My equipment is an RCA DTC-210 D* box and an FM trap with 100ft of cable to my RCA 58” UHF/VHF antenna on the top of my roof. I have been able to get these results.

Chan Station Network Compass Dist Freq Tower Power My reception
8.1 KTUL-DT ABC 114° 23.9 10 1779 ft 7kw 80%
23.1 KOKI-DT FOX 109° 19.0 22 1312 ft 1,000kw 40%
11.1 KOED-DT PBS 109° 19.3 38 1299 ft 500 kw 70%
41.1 KTFO-DT UPN 109° 19.0 42 1250 ft 900 kw 0%
6.1 KOTV-DT CBS 109° 19.3 55 1609 ft 300 kw 80%
2.1 KJRH-DT NBC 109° 19.3 56 1657 ft 800 kw 80%

I tried an CM 7777 amp and it cuts out all my channels to 0%, I also tried a Radio Shack variable attenuator and that does nothing to most channels even if I turn it all the way up to max attenuation, but other than that does not affect the # of channels I get. My analog channels seem to have ghosting but I am not sure how to get rid of that (I have aimed the ant in every direction).

I hooked up a $10 bottom of the line UHF/VHF rabbit ear set and stuck it by my window and got these results…

Chan Station Network Compass Dist Freq Tower Power My reception
8.1 KTUL-DT ABC 114° 23.9 10 1779 ft 7kw 70%
23.1 KOKI-DT FOX 109° 19.0 22 1312 ft 1,000kw 80%
11.1 KOED-DT PBS 109° 19.3 38 1299 ft 500 kw 70%
41.1 KTFO-DT UPN 109° 19.0 42 1250 ft 900 kw 90%
6.1 KOTV-DT CBS 109° 19.3 55 1609 ft 300 kw 80%
2.1 KJRH-DT NBC 109° 19.3 56 1657 ft 800 kw 10%

So basically my rabbit ears are performing as well if not better than my tripod mounted, 20ft off the ground, 58” long boom, combo antenna.

I don’t want to have to haul out the rabbit ears every time I want to watch UPN or Fox. Man this project has been a nightmare. Any advice on what to do from the experts here?

-A very frustrated Pokelahoma :confused:

Sounds like multipath issues. At that range you shouldn't need a huge antenna. I recommend going to a Best Buy ( I know you have them out there , I've been to Norman and OKC) and trying out the Winegard Square Shooter. They actually sell it in a Terk Box. Move the antenna around your roof area to try and get the best signal possible. Once you find the right spot you'll know it. What helped me is the signal strength meter on my Dish 811. Also, for a distribution amp, I purchased a Winegard 04050 for $60, and it bumped up all my signals by 5%. You can read up on all antenna topics here: www.antennasdirect.com

Pokelahoma

12-03-04, 05:49 PM

blackngold19,

I thought about the squareshooter but then I would lose my VHF channel (ABC). I am thinking of trying a better set of rabbit ears like the RS 15-1880.

greywolf

12-03-04, 11:13 PM

The SqS doesn't do as well as other popular UHF antennas. The Terk labeled version adds 50% to the cost of an already too expensive antenna.

jimc705

12-04-04, 10:54 AM

pokelahoma,

I had a similar problem. The higher I went the worse the signal.
I'd try an antennas direct xg91 UHF antenna on a 10 foot mast and try different spots on your property. I recommend this antenna for it is low wind resistance, very light, has extremely high gain on the upper UHF channels. The best part if it doesn't work you can return it for full credit. The best antenna warranty in the business. It may also pick up the high VHF channel 10 at your distance. I'm 7 miles from channel 2 VHF here and it receives channel 2 very well. You may not need a VHF antenna. It may take some time and patience to find the exact location. Also try different heights. A few feet one way or the other may make the difference. You probably find a sweet spot where you'll get all the channels well but may scrafice some signal strength on others.

The preamp is probably over loading the receiver for you are very close to some channels (especially channel 8 dt 10). I have a problem with channel 2 here. It wipes out everything from it's direction including the UHF digitals and I have no amp. You are almost pointing right at channel 8's tower. If you find you need an amp, you'll need something with less gain and high front end input. Winegard 8700 has both. WWW.winegard.com or see link below. Note the high input voltage for strong signals and less db gain.
http://www.winegard.com/offair/pdf/Chart29.pdf

May also try the 4700 for it just passes VHF with no amplification. I think you being 10 miles from channel 8 DT 10 is overloading. A UHF only antenna will also help solve this problem.

I know this sounds dumb but make sure the antenna is pointing in the right direction. The large VHF elements should be pointing away ( if V formation) or be at the opposite end from the station you are trying to get. If you're not sure turn it 180 degrees and try again. You don't know how many people do this wrong and waist a service call for aiming the antenna.

I see no reason for KTFO at 90% on the ears and 0 on the combo other then the digtal may have been off air . Digitals do go off air more so then analog. They have transmitter problems, or some stations only run at certain times of the day. I've seen digitals here off air for days at a time. In very rare cases you can get a bad antenna. about 1 in a million though.

I'd also double check the f connectors and make sure no wires are touching . One strand from the ground to the center conductor is all it takes to kill reception. I've also seen people swear it's correct and you take the f connector off and find the center conductor bent over and not in the center hole.

Here's their link to KTFO coverage area.
http://www.fcc.gov/fcc-bin/FMTV-service-area?x=DT618058.html

You can also check the other stations coverage area to be sure you're in their coverage area at this link.
http://www.fcc.gov/fcc-bin/audio/tvq.html
Just punch in the call sign then click on DT channel and map (41dbu) coverage.

I believe this will solve your problem. I'd start with checking connections for that is free.

If possible try moving your combo antenna around the yard and roof. Most combos are difficult to do this for they are huge. Your's being only 58 inches you may be able to do this. The RCA antennas are under performers and just may not do the job. Especially on UHF/VHF at 58 inches and the furtherest station at 56 miles this is where they usually save money and put a short distance UHF on a combo antenna. Seperates will do a much better job.
I don't think you need an amp if you get 10% on the weakest channel of the ears. Try first with no amp. You can always add an amp later if needed. If you do need an amp you almost certainly will need a UHF only amp. Your VHF channel is too close thus the problem with the 7777 CM. I think you can use the 7777 as a UHF only by changing switches inside the amp. You can try that but I think with 28DB gain you still might overload even on UHF.

If all else fails try the xg91. It's one of the best yagis on the market and has a lifetime warranty. Good luck I hope this helps.

Pokelahoma

12-04-04, 11:57 PM

Thanks for the advice Jimc I have totally replaced all my cables and connectors already, and I also have my antenna aimed correctly and have tried every other direction. I am positive that the Fox and UPN channels were broadcasting since I can pick them up on the little loop fine.

I tried a better set of rabbit ears (the RS 15-1880) and got zero channels, so now I am definitely leaning toward doing a separate UHF and VHF antenna. I am listed as 23.9 miles away from my VHF ABC DT 10 channel so I am not sure if I would be able to make do with just a VHF antenna or not, or if they are overpowering me. I am unsure about buying an xg91 though since it seems to be rated for extreme fringe and I am 20mi from my towers and seem to be able to attenuate 20db off most of my channels and still receive them fine. Fox DT 22 and UPN DT 42 are my only problem channels. Those channels seem to love the simple loop antenna and not my big antenna.

Thanks.

sregener

12-05-04, 08:02 AM

Originally posted by Pokelahoma
I am unsure about buying an xg91 though since it seems to be rated for extreme fringe and I am 20mi from my towers and seem to be able to attenuate 20db off most of my channels and still receive them fine.

The "larger" antennas have two things going for them. First, they have high gain. But secondly, they are very directional. (As Mark Twain would say, "But I repeat myself." Seriously. The higher the gain, the more directional the antenna. Fact. Period. This can help with multipath, but I don't think it would solve the issue in your location.

My best advice would be to try a 4-bay bowtie (Antennas Direct DB4, Channel Master 3021 or Winegard PR-4400) antenna. But even that may not work.

You may be one of those people who really need a 5th-generation LG STB to get reliable reception. They're supposed to be out 1st quarter 2005, so rather than playing with antennas forever, a different tuner could solve all your problems. The 5th-generation chipset supposedly fixes almost all reception problems related to multipath (ghosting on analog.)

cpcat

12-05-04, 08:41 AM

Originally posted by Pokelahoma
I am unsure about buying an xg91 though since it seems to be rated for extreme fringe and I am 20mi from my towers and seem to be able to attenuate 20db off most of my channels and still receive them fine.
------------------------------------------------------------------------------

You're FOX is only 4kw right now which could explain your problem there. The inconsistency you found when you tried the other indoor antenna is likely due to tropospheric variation. The unusual event was likely the reception on the indoor bowtie initially. Here's the FOX station info from the FCC:http://www.fcc.gov/fcc-bin/tvq?call=KOKI. At 20 miles, you're within the 41dbu window but that assumes an adequate outdoor antenna.

UPN is supposedly at full power and so I'm a little surprised at your problem there. Assuming they don't have a problem with their transmitter, it's likely multipath as others have said. There are two ways to overcome multipath: higher gain and narrower beamwidth. Luckily, you get both as you go up in antenna size.
I wouldn't go with a 4-bay. You need either a large, directional yagi/corner reflector like the xg91(and others) or an 8-bay bowtie such as the CM 4228.
The 8-bay would more likely recieve ch. 10 so maybe that should be your choice. Don't use a preamp (will make multipath worse) and I wouldn't worry about overloading the reciever as long as you don't. If that still doesn't work and you don't want to wait for the 5th gen. receiver chips, you may have to stack. See http://www.atechfabrication.com/reception_solutions.htm for other ways to deal with multipath.

Chad0429

12-05-04, 11:42 AM

Quick question - I'm looking at the Winegard models (VHF/UHF/FM) for my attic.

I'm 40-45 miles out from both UHF and VHF broadcasts. Am I better off getting the top end that is rated at

HD8200P or PR7052
Deep Fringe
VHF = 100 Miles
UHF = 60 Miles

or

HD7084P or PR-7042
Fringe
VHF = 80 Miles
UHF = 45 Miles

Both are within my ranges but the lower one is closer to it's limits.

Do I stand a better chance of getting good reception with the larger of the two (if it will fit in my attic)?

Is there going to be any problems with an antenna that gets FM plus the others too? Do they make just a UHF/VHF with no FM? Will there be interference issues?

Do I need other equipment - my TV has an OTA tuner built in.

Thanks and sorry for the barrage of questions. :)

cpcat

12-05-04, 01:19 PM

HD8200P or PR7052

You might as well save yourself some time and forget the attic at that distance. You might get inconsistent reception but chances of getting consistent reception are low. The ratings you mention are approximations and refer to the antenna installed *outside*.

If you want a combo antenna, go with the 8200p; you can't have too much antenna.

Another option would be to go separate uhf and vhf, like a CM 4228 and a 10 or 5 element high band (7-13) vhf antenna (I don't know if you need low band 'cause I don't know where you are). If you need low band (2-6), best stick with the combo antenna but you can get better performance from separating them. If separate, you'll need a vhf/uhf diplexer like the CM 0549 or you might consider the CM 7777 preamp at that distance (depending on the length of your cable run, >50 ft I'd go with the preamp in your case). The CM 7777 will diplex for you or also has a combined input if you go with the combo.

FM interference is a concern. If you use the CM 7777 it has an FM trap built in. If not, you might need an FM trap (Winegard makes one).

Other than the antenna, etc., it looks like that's all you'll need.

HalfCracked

12-06-04, 01:41 AM

couple of questions...

Is there a qualatative difference between a Terk HDTVi pro (yeah I know) & a Zenith Silver sensor? Besides the price that is?

What can I do to deal with Extreme multiplexing? Counted as many as 6 ghosts on analog 26. (tried an anttenuator)

How do you check for multiplexing on a digital channel? if I can't see it how do I use "non-Intuitive antenna directions".:confused:

for reference see my posts (#264 & 266) in the Houston OTA thread.

jimc705

12-06-04, 09:05 AM

half cracked,

Personally I stay far away from anything made by terk. Their antennas are extreme under peformers. The Zenith silver sensor is a very good indoor antenna but if you have multipath it may not help much.

If you have ghost on analog you more then likely have a multipath on digital from the same direction. You can sometimes tell by the signal strength bar / percentage number, if you receiver has one, while on a digital channel. If it varies widely 0 to 60 , 40 to 80 etc. then you more then likely have multipath.

The only solution for multipath is to get a good directional antenna and get up as high as you possibly can. Multipath is tv signals being reflected of buildings trees etc to arrive at your antenna at different time. This is why you see ghost on the analog channel. Like drivng a car straight 2 miles or going another route and going 4 miles to get to the same point. It takes longer to go 4 miles and you'll arrive later then the 2 mile route. Also weaker (less gas).

I don't know how close you are to the transmitters but the silver sensor
is suppose to be somewhat dirrectional and if very close it may do the job.
Be sure you can return it if it doesn't. The best indoor while some what ugly is the double bow tie available from radio shack by special order only.
http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&product%5Fid=930-0998

If this doesn't do it then you must go outside for reception. Check with antennaweb.org first and see what comes up. Good Luck.

jimc705

12-06-04, 09:45 AM

Chad,

If you put the antenna in the attic you may have severe multipath issues and you loose up to 40% or more efficency of the antenna. Thus a 100 mile rating quickly drops to 60 miles even without the multipath issues. The mileage ratings on antennas are a guideline and not gospel. Most are rated over flat terrain or water and do not give you real life situtations. Channel Master and Winegard do rate theirs over average terrain. Whats average? beats me. Cheaper brands rate theirs over water for maxium reception.

Seperate antennas will give you better reception as CP cat metioned. If you just want digital reception then you may only need a UHF and not need a VHF. UHF antennas are much cheaper and you can save a bunch of money. Go to antennaweb.org and plug in your address to see what channels your digitals are on, most are UHF. The seperate antennas CPcat recommends are about the best in the industry and should have no problems at your distance.

If you must go with a combo the 8200 will more then do the job. I have the hd7084p over moutaineous terrain and pick up very good and reliable digital and analog reception out to 70+ miles with no amp. The mountains in that direction are distant though about 1 mile or more from my antenna. The other direction I'm about half way up a hill, and must tilt the antenna 15 degrees to get up and over. That cuts my reception to about 45 miles.

You can try the attic but count on moving it outdoors. One other problem with the attic. The antenna hd 8200 is very large. You must have enough room to turn that monster in the direction of the stations. Most attics don't have that kind of room. Good luck and happy viewing.

Chad0429

12-06-04, 09:56 AM

Jim,

Thanks for the response.

All but one of my channels in the Dallas/Ft Worth area are UHF, however one major channel is on VHF, so I need both. I'm only looking for HD stuff as I have D* for other channel viewing.

Attic space is an issue but I don't think (i hope not) I need to turn the antenna as all my stations are within about 4 degrees of each other (163-167 degrees from due North).

I have seen a stand or something that allows me to mount the antenna off of my sattelite dish on my roof as well. I think that's probably the best bet, if not then I'll probably try to rig something up to strap to my chimney.

I'll check into some of the other answers cpcat spoke of as well.

sregener

12-06-04, 10:02 AM

Originally posted by Chad0429
Quick question - I'm looking at the Winegard models (VHF/UHF/FM) for my attic.

1) Do I stand a better chance of getting good reception with the larger of the two (if it will fit in my attic)?

2) Is there going to be any problems with an antenna that gets FM plus the others too? Do they make just a UHF/VHF with no FM? Will there be interference issues?

3) Do I need other equipment - my TV has an OTA tuner built in.

1) Larger is almost always better. (Exception: when trying to receive stations that are 15-30 degrees apart, a fixed installation of a smaller antenna will work better than a fixed installation of a larger one. Larger antennas are more directional.) Attic installations cost you a minimum of 50% of your signal. Depending on your roof materials, topography, and other unknowns, you might get a good signal in the attic, or you might get nothing.

2) If there would be a problem with FM, it wouldn't matter if you had an FM antenna or not. You can always purchase an FM trap after the fact if you suspect that FM stations are causing you problems. No lo-VHF (channels 2-6) antenna is made that doesn't also receive FM since Channel 6 is at the bottom of the FM scale at around 86-88Mhz.

3) You might want a preamplifier, but only if your multipath issues are minimal. Look for a low-noise one such as the Winegard or Channel Master models. (Beware the CM 7775, it will not even pass VHF.)

cpcat

12-06-04, 10:58 AM

I'm only looking for HD stuff as I have D* for other channel viewing

In that case everything is uhf except for ABC on ch. 9. If you really want to try the attic, and you have all your stations within a 5 degree window, you could try an 8-bay (Antennasdirect DB8, CM 4228, Winegard 8800). This *might* also provide enough gain on vhf 9 to get your ABC. If you've decided to go outside, you might get away with a 4-bay for the full-power stations (CM 4221, DB4). The problem is that that's about the edge of reception range even outside for a 4-bay. The more cushion you have, the more consistent it will be and the fewer dropouts you'll have. An 8-bay or large combo vhf/uhf will require a sturdy mount (ground mount, guyed roof mount). I certainly wouldn't try mounting to the dish and chimney mounts are difficult and not as sturdy.

A ground mount is not that difficult and is very sturdy. Here's a pic of mine:
With a 4-bay, you could just do a wall mount (i.e. the top two attachments only) but bringing it to the ground is much stronger (I'd recc. if you go the 8-bay or large uhf/vhf combo route).

dt2002

12-08-04, 12:13 AM

My HDTV is located in the finished portion of my basement. It is also close to where the cable enters the house. From the basement, there is one cable that travels through the wall to the attic. From there, it splits (and is amplied) to deliver cable to the upstairs bedrooms.

Here is my question...

If I mount an antenna in the attic, is there someway of running the antenna signal down to my HDTV through the line that runs from the basement to the attic? Is this possible even though the cable the signal is "going the wrong way"? If it is possible, what equipment do I need? Combiners? Diplexers? others?

Thanks!

jimc705

12-08-04, 12:41 AM

dt,
Not exactly sure what you are trying to do. If I have it right you are try to feed an off air antenna on the same line that is now be used for cable TV. If so no you cannot combine off air with cable. Your need a seperate coax for the off air signal.

I don't know where you are located but you may not need an external antenna. Then you can get a small indoor antenna for hd. This is very rare though unless you are very close to the transmitters. Check with antennaweb.org put in your address to see what kind of antenna you'll need.

jdspencer

12-08-04, 01:59 PM

I posted in my city's reception area, but not too many people visit there. :)
So if someone can reply to this thread (http://www.avsforum.com/avs-vb/showthread.php?postid=4773960#post4773960) I'd appreciate it.

dt2002

12-08-04, 02:25 PM

Originally posted by jimc705
dt,
Not exactly sure what you are trying to do. If I have it right you are try to feed an off air antenna on the same line that is now be used for cable TV. If so no you cannot combine off air with cable. Your need a seperate coax for the off air signal.

I don't know where you are located but you may not need an external antenna. Then you can get a small indoor antenna for hd. This is very rare though unless you are very close to the transmitters. Check with antennaweb.org put in your address to see what kind of antenna you'll need.

Jim - you got it right. I wanted to share the same cable between the antenna and the cable signal. I know it's possible to combine cable and satellite TV. I just did not know if I could combine OTA antenna and cable TV.

auburn97

12-08-04, 04:42 PM

I have a CM 4228 UHF antenna in the attic, and our local ABC affiliate decided to broadcast VHF. So, I need to get a VHF-only antenna (the ABC tower is in a different location than the UHF broadcasts) and combine the signals. Can I just get any old splitter/combiner?

Other information-
Cable run of 40 feet
I have a CM 7777 preamp near the TV (should I move this toward the antennas?)

dswallow

12-08-04, 05:20 PM

Originally posted by dt2002
Jim - you got it right. I wanted to share the same cable between the antenna and the cable signal. I know it's possible to combine cable and satellite TV. I just did not know if I could combine OTA antenna and cable TV.
The reason OTA or Cable can share the line with the satellite signals is that OTA/Cable generally uses the 50-850MHz range and satellite LNB's use the 950-1450MHz range, so there's no overlap and sufficient spacing.

Since OTA & Cable would be using the same frequencies, you can't share a cable.

sregener

12-09-04, 10:02 AM

Originally posted by auburn97
I have a CM 4228 UHF antenna in the attic, and our local ABC affiliate decided to broadcast VHF. So, I need to get a VHF-only antenna (the ABC tower is in a different location than the UHF broadcasts) and combine the signals. Can I just get any old splitter/combiner?

Other information-
Cable run of 40 feet
I have a CM 7777 preamp near the TV (should I move this toward the antennas?)

While you could use a normal splitter, it wouldn't be best. The best would be to move your 7777 up to the attic, as it has separate inputs for UHF and VHF. Just plug the proper antenna into each input and you're good to go. Otherwise, I'd suggest the Channel Master #0549, which filters out unwanted frequencies while combining antennas (note - this is exactly the same thing that is in your 7777.)

jimc705

12-09-04, 10:13 AM

auburn.
You did not metion how close you are to the VHF 4 YOU ARE TRYING TO GET. If you are very close try to put the 7777 to combined input. The switches to do this are inside the amp. You may get lucky and get enough signal from the 4228. It does pick up some VHF, although 4 is going to be tuff. The amp has 23 db gain VHF.

If that doesn't work the 7777 amp is suppose to be up at the antenna. The white power supply by the tv set inside. The amp (gray part) has seperate inputs for VHF/UHF so it will combine the signals for you. Then you'll need a low band yagi.
http://www.starkelectronic.com/acantena.htm#Y5

This will work if you are fairly close. You'll have to go to www.antennaweb.org
and see what size antenna they recommend. You may need a 10 element.

You may also find if you move the 4228 outside you may get channel 4 off the backside of the antenna. The low band yagi has long elements so you must have enough room in the attic to point in the direction of the station.

auburn97

12-09-04, 10:18 AM

Thanks for the replies- I was mistaken, the 7777 is in the attic, it is the white power supply down by the TV I was thinking was the 7777 for some reason. Anyway, I am 16.2 miles from the VHF tower, and 44 miles from the UHF tower, so my UHF antenna is HIGHLY sensitive to directional changes. The two towers are 90 degrees from each other, so it looks like I'm stuck going with two separate antennas.

cpcat

12-09-04, 10:50 AM

Auburn,
You might try making your own simple dipole with 300 ohm twinlead and mounting it in your attic (horizontal and perpendicular to the direction of the tower). You'd cut the proper length, splice it together at both far ends, then attach it to a 300/75 ohm balun in the middle (you'll have to splice the bottom wire in the middle to the balun, thus making a loop). See http://www.kyes.com/antenna/rabbitear.html for lengths .

An FM antenna dipole might work but it wouldnt' be optomized for ch. 4.

jimc705

12-09-04, 11:13 AM

JD

Sounds like multipath. The radio shack amp may be the whole problem. Rat shack amps are very noisy (4 db and up) and cause more problems then they solve. Try taking out the amp first. Being only 8 miles from transmitter you shouldn't need any amp. Work with no amp first and if you find you need one you can add one later.

Also radio shack makes a cable amp which does not include all the UHF band (WSKG) . You may have mistakenly got a cable tv amp. I think the amp you have is for distribution and won't help for the antenna.

If you find later on you still need an amp. You'll need a 2 piece preamp like a Winegard AP 8700.
http://www.winegard.com/offair/pdf/Chart29.pdf
Has very high VHF/UHF input voltage for reducing overloads from strong stations and 16db gain for the weak signals.

If removing the amp doesn't do it you may need to move the antenna up above your roofline to lessen the multipath. Multipath on a digital signal will sometimes completely wipe out the channel. No ghost but then nothing. Again try without the amp.

I know this sounds crazy but make sure the V on the antenna is pointing away from the stations you are trying to get and not towards them. In other words the UHF part shoud be closest to the stations you are trying to get. This is a common mistake some people do. They think the V is like an arrow and should point toward the station which is backwards.

The 3016 is not great at multipath. May need to get the ghost killer at http://www.winegard.com/offair/platinum.htm#7210
only if all else fails.

I'd definetly return the amp and try without. If you get up above your roofline this should cure your problems. Good Luck.

jimc705

12-09-04, 11:29 AM

CPCAT,

Great recommendation!!

I am 42 miles from channel DT 7 here and made a small dipole cut for channel 7 with twin lead. I used PVC 1/2" pipe and put it inside along with the balum to help make it water proof. Works great at 40 miles so you should have no problem. If in attic no need to make waterproof but 50% reduction in efficency.

You may find this useful on how to make a dipole.
http://www.wfu.edu/~matthews/misc/dipole.html

jdspencer

12-09-04, 04:24 PM

Thanks for the input. I removed the RS amp, which is a two piece version, not a distribution amp. The result was no difference.

Interesting about the multipath, since at one time I had the antenna just 6 feet above the deck and was able to get 42. Moved the antenna higher and I lost it.

I guess I really need to get this thing above the roofline, especially since my house has steel siding. :)

powerusr

12-10-04, 12:05 AM

Hi,

I could not find a better place to ask this question. Sorry in advance.

I am tiring to find out what Antenna DirecTV installs when you purchase their HD Solution. I found it in the past but have not been able to find it recently. My Guess is that it is what ever they have on hand.

Thanks
John

neitzb

12-10-04, 04:58 PM

I'm working on pulling in DTV OTA and am not going to be able to do it without an amp. So here's my run: RS Yagi to preamp to 3x4 multiswitch (combined with Directv) to diplexer to amp to tv (integrated tuner). Understanding that the amp and pre-amp puts voltage on the line between the two amp components, what should I do. In other words, is it possible to use a pre-amp and amp over diplexers and mutliswitches with Directv? I already have a triple run to this TV and I've been "cutoff" from running any more. Thanks!

greywolf

12-10-04, 05:39 PM

All the amp/preamp/amp power supply components need to go between the multiswitch and the antenna. Multiswitches and diplexers must block DC to allow the DC used as a 13VDC/18VDC signal and power between the DirecTV receiver and the dish LNBs. The only exception is when that 13VDC/18VDC is also used to power the amp/preamp and a dual passthru diplexer is used at the antenna end.

A 3x4 multiswitch can only access Sat A so prevents reception of most HD programming. A 5x8 is required with 4 lines from the dish and one from the antenna.

psxjunky

12-10-04, 11:17 PM

I have a CM 4228 installed in the attic and also using a CM 7777 pre-amp with it.

I am getting good signal strentgh on a bunch of channels, but on a few others I am getting a lot of stutter.

I am contemplating moving the CM4228 outside (rooftop) but would like to know how much improvement I can expect.

Can someone give me a ballpark figure about typically how much signal strength you lose by installing this antenna in the attic versus outside (on the rooftop) ?

Also, does anyone know how directional the Cm4228 is ? I have read conflicting reports where some say the 4228 is not directional and some say it is highly directional.

neitzb

12-10-04, 11:53 PM

Originally posted by greywolf
A 3x4 multiswitch can only access Sat A so prevents reception of most HD programming. A 5x8 is required with 4 lines from the dish and one from the antenna.

Thanks Greywolf, I'll give it a shot. Regarding your comment about the 3x4 vs a 5x8 preventing HD programming, are you referring to HD programming over satellite (from the LNBs) or will this also impact the HD signal coming OTA? I don't have the D* equipment to pull in HD over the satellite and have no plans on adding it because the cost is ridiculous for a receiver with Tivo. So I was just looking to supplement my locals with OTA HD for a better quality option for HD shows and sports.

dswallow

12-11-04, 12:12 AM

Originally posted by neitzb
Thanks Greywolf, I'll give it a shot. Regarding your comment about the 3x4 vs a 5x8 preventing HD programming, are you referring to HD programming over satellite (from the LNBs) or will this also impact the HD signal coming OTA? I don't have the D* equipment to pull in HD over the satellite and have no plans on adding it because the cost is ridiculous for a receiver with Tivo. So I was just looking to supplement my locals with OTA HD for a better quality option for HD shows and sports.
OK, you are currently using a 3x4 multiswitch so you have a regular 18" dish, right? Not the 3-LNB Phase III dish.

You cannot feed the DC voltage to power the preamp along the coax lines used for the DirecTV signal because it would conflict with the control voltages used to tell the multiswitch what polarity LNB signal to deliver.

With the 18" dish, there's 2 lines from your satellite dish to the multiswitch. You mention you have 3 coax lines run. What you could do is dedicate one of those to the antenna and preamp and the power injector for the preamp. Bring the other two directly from the LNB's on the 18" dish inside and place the 3x4 multiswitch there and feed your receivers from the multiswitch and the OTA HD receiver from the 3rd coax.

greywolf

12-11-04, 12:32 AM

Originally posted by neitzb
Regarding your comment about the 3x4 vs a 5x8 preventing HD programming, are you referring to HD programming over satellite (from the LNBs) or will this also impact the HD signal coming OTA? Just the satellite.

neitzb

12-11-04, 11:09 PM

[QUOTE]Originally posted by neitzb

Thanks Greywolf and Doug. Success at last. The third run I have actually comes back downstairs to another TV that I control off of one receiver (don't use it much so don't want to pay the extra), so I didn't want to use that third run. But from taking your advice, I moved the power supply from right before the TV to before the multiswitch and it made all the difference. Now I just can't wait until tomorrow to see how football looks in HD. Thanks for all your help, I would have given up without it.

dswallow

12-12-04, 01:19 AM

Originally posted by neitzb
[QUOTE]Originally posted by neitzb

Thanks Greywolf and Doug. Success at last. The third run I have actually comes back downstairs to another TV that I control off of one receiver (don't use it much so don't want to pay the extra), so I didn't want to use that third run. But from taking your advice, I moved the power supply from right before the TV to before the multiswitch and it made all the difference. Now I just can't wait until tomorrow to see how football looks in HD. Thanks for all your help, I would have given up without it.
Are you running the power injector connected to one of the lines from the LNB?

I wouldn't.

There's still a control voltage being sent from the multiswitch to each LNB to identify what polarity to set the LNB for; either 13v or 17v. Maybe you got lucky and have it on one that's close to the voltage of the preamp power injector, but it's probably delivering more voltage than the LNB normally would take, and putting two DC sources on the same line might cause some problems in other circuitry.

neitzb

12-12-04, 01:32 AM

Originally posted by dswallow
Are you running the power injector connected to one of the lines from the LNB?

Nah. The 2 LNB lines go directly into the multiswitch, and the yagi, preamp and power supply are all on the antenna input of the multiswtich. So none of the amp components are on the LNB lines.

dominicr

12-12-04, 03:51 PM

Originally posted by psxjunky
I have a CM 4228 installed in the attic and also using a CM 7777 pre-amp with it.

I am getting good signal strentgh on a bunch of channels, but on a few others I am getting a lot of stutter.

I am contemplating moving the CM4228 outside (rooftop) but would like to know how much improvement I can expect.

Can someone give me a ballpark figure about typically how much signal strength you lose by installing this antenna in the attic versus outside (on the rooftop) ?

Also, does anyone know how directional the Cm4228 is ? I have read conflicting reports where some say the 4228 is not directional and some say it is highly directional.

I have heard figures of 30-50% signal loss in the attic. I personally had to go rooftop after not getting satisfactory results in my attic. I am only about 12 mi. away too.

psxjunky

12-13-04, 05:15 AM

Thanks dominicr !

How much was the improvement for you by going from attic to rooftop ?

jimc705

12-13-04, 09:52 AM

Dominicr,

The 4228 is a directional antenna with an average beamwidth 37 degrees. This doesn't mean you absolutely won't pick up anything from the sides it just has to be about 15 DB stronger then what's it front. Front to back 22DB. Note the gain per channel starts at channel 14 10.8 db and goes to a high of 13 DB at channel 52. These are of course in open air and not attic .

A tech at Channel Master provided me with these specs on various antenna model. For some reason, there specs are not posted on their Web site. Enjoy.

Note: These are comma-aligned tables. Copy and paste into a text editor to realign the tables if necessary)
The 4228 specs are 4th column in.
Table 1 - Gain specs

Antenna Model 4251 4228 4248 3023 3021/4221 4247 4194 4308/3022
Channel Frequency(MHz) Gain Gain Gain Gain Gain Gain Gain Gain Gain
14 470 14.5 10.8 10.2 9.3 8 7.4 5.8 5.4 5.8
19 500 15 11.7 10.6 9.7 8.3 7.2 5.9 6 5.9
27 548 13.5 12.1 11 10.5 9.4 7.2 6.4 6.2 6.4
35 596 16.2 12.1 11.4 10.8 10 7.2 6.9 6.9 6.9
43 644 16 12.7 12.4 11 11 8.5 7.6 6.2 7.6
52 698 16.4 13 13 12.4 12 10 8.4 9.8 8.4
60 746 17.6 11.5 11.8 11.8 12.9 9.5 9 9.8 9
69 800 17.8 11.5 6.2 8.7 12.8 9.5 9.6 -0.8 9.6
Average Gain 15.9 11.9 10.8 10.5 10.6 8.3 7.5 6.2 7.5

Size 6.96 2.77 2.56 2.56 0.9 1.02 0.83 0.51 0.83
Length NA NA 82 82 NA 47 NA 41 NA

Table 2 - Polar specs

antenna model 4251 4228 4248 3023 4221/3021 4194 4308/3022
Channel Freq.(MHz) "BW, F/B" "BW, F/B" "BW, F/B" "BW, F/B" "BW, F/B" "BW, F/B" "BW, F/B"
14 470 "20deg, 14db" "37deg, 22db" "42deg, 17db" "43deg, 18db" "59deg, 17db" "63deg, 17db" "56deg, 21db"
19 500 "19deg, 16db" "29deg, 23db" "36deg, 22db" "37deg, 19db" "57deg, 16db" "62deg, 17db" "54deg, 19db"
27 548 "16deg, 14db" "26deg, 21db" "32deg, 19db" "37deg, 23db" "54deg, 15db" "59deg, 17db" "52deg, 20db"
35 596 "15deg, 14db" "24deg, 19db" "30deg, 21db" "34deg, 16db" "52deg, 17db" "58deg, 15db" "48deg, 15db"
43 644 "14deg, 15db" "23deg, 24db" "27deg, 24db" "32deg, 17db" "48deg, 16db" "57deg, 14db" "43deg, 18db"
52 698 "13deg, 15db" "20deg, 21db" "23deg, 18db" "31deg, 19db" "44deg, 17db" "53deg, 12db" "37deg, 20db"
60 746 "12deg, 14db" "18deg, 20db" "20deg, 15db" "24deg, 18db" "41deg, 15db" "50deg, 12db" "31deg, 16db"

The loss in the attic depends on roofing material and what else may be in the attic. HVAC runs, Electrical wiring, type of insulation etc. Ball park is
40 % less efficency. Multipath problems are also a big issue with attic insulations. This can completely wipe out a station or at very least create a lot of drop outs. You'll see a big improvement if you move outside location.

goldrich

12-13-04, 12:24 PM

Originally posted by psxjunky
How much was the improvement for you by going from attic to rooftop ?

FWIW, sometimes you just have to forget about the gain figures and go on local recommendations or just grab an antenna and try it at your particular location. Here in Indy a couple of us have been conducting some tests between the CM 4221 and the 4228 to receive our local WB station on digital channel 48 which is currently running only 4 kW @ about 1000 feet. Also, the station's tower is located several miles outside the immediate metro area. I live 36 miles from the tower and another local viewer is approximately 30 miles from the tower.

With the above in mind, neither antenna would work in either one of our two attics. Then we tried the two antennas outdoors at around 15-20 feet AGL. The 4228 barely moved the signal meter reading, but when each of us hooked up the 4221 we had some very satisfactory results. Neither one of us is getting a super signal but the signal level is very decent and strong enough to get a pretty stable/reliable signal. The gain specs for the 4228 would lead you to believe that it would be the better choice for receiving ch. 48, but for this area the 4221 is a much better performer on DTV ch. 48.......BTW, just for clarification, we did not use any preamps for these tests.

Steve

cpcat

12-13-04, 02:44 PM

The 4228 will be much more sensitive to aiming due to it's narrower beamwidth compared to the 4221. The beamwidth becomes even narrower the farther up in frequency you go. In addition, reception of marginal signals can change minute by minute so I'd take those results with a grain of salt. The 4228 should give the better signal assuming matched conditions and precise aiming for both.

etcarroll

12-13-04, 03:14 PM

Another thing about the CM 4228, I have one and learned on another forum that the 4228 rolls off sharply above channel 60 as it is shipped from the factory, but you will pick up almost 5 db gain if you trim the elements at the scoremarks on thebowties.

goldrich

12-13-04, 03:58 PM

Originally posted by cpcat
The 4228 will be much more sensitive to aiming due to it's narrower beamwidth compared to the 4221. The beamwidth becomes even narrower the farther up in frequency you go. In addition, reception of marginal signals can change minute by minute so I'd take those results with a grain of salt. The 4228 should give the better signal assuming matched conditions and precise aiming for both.

The key word is "should." In theory I agree with everything you've said but in reality I've tried this same test at various times of the year and I've gotten similar results. In my experience, the 4228 doesn't always outperform the 4221, even with precise aim using a rotor. At various times I've used each of these antennas in permanent installations. And, yes, I do agree and I know from personal experience that the beamwidth is much narrower with the 4228 and that multipath issues are generally much worse with the 4221.

Location, location, location...........your results may vary. The two test sites were at least 12 miles apart, we each used our own set of antennas (4221 and 4228) but we ended up with very similar results for this one station.

I'll stick with my horizontally-stacked Triax Unix 100 antennas which totally outperform the 4221 and the 4228 on weak stations at my location.

Steve

tivoboy

12-13-04, 04:48 PM

Originally posted by etcarroll
Another thing about the CM 4228, I have one and learned on another forum that the 4228 rolls off sharply above channel 60 as it is shipped from the factory, but you will pick up almost 5 db gain if you trim the elements at the scoremarks on thebowties.

care to elablorate here, with a diagram maybe?
I'd love to increase the high range

cpcat

12-13-04, 05:05 PM

It's not likely you could increase the gain above 60 without negatively impacting performance on the lower channels. There's not much, even now, above 60 anyway and eventually *everything* will be 51 and lower.

etcarroll

12-13-04, 05:54 PM

"care to elablorate here, with a diagram maybe?
I'd love to increase the high range"

Just look at the 'whiskers' on the actual elements, there's a scoring, or start of a cut, on each, just finish it by cutting all the way thru.

cpcat makes a good point, if you don't have channels above 60, then don't bother. In Philly, I have 2 channels above 60, so it works for me.

cpcat

12-13-04, 06:06 PM

In case you're interested:

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=481958

jimc705

12-13-04, 11:15 PM

CPCAT,
Plan on stacking my xg 91's which look almost identical to your Triax Unix.
Do you have a spacing recommendation for the antennas?
You make the stacking mount or buy?
I assume the coax has to be exact length from each antenna.
What did you use to combine both UHF's together?
Thanks for help in advance.

jimc705

12-13-04, 11:17 PM

OOPS forgot . Why you stack horiz. instead of vertical. I assume horz. stack gives narrower beamwidth is this correct?

cpcat

12-14-04, 08:12 AM

OOPS forgot . Why you stack horiz. instead of vertical. I assume horz. stack gives narrower beamwidth is this correct?

Yes, correct. Horizontal stacking has always worked better for me. It's probably due to it's ability to reduce multipath in mountainous terrain.

I settled on 48 inches for stacking distance. 44 and below, performance suffers for me. Wider than 48 works fine but doesn't seem to give any improvement in performance and the beamwidth gets very narrow and makes aiming more difficult, more dropouts on windy days, etc.

With my Televes stack, I liked 57 in. though, you'll have to experiment some.

I use a Lindsay uhf 2-input combiner. It offers a small improvement over a wideband splitter in reverse. You might go with the splitter first before deciding to fork over the cash for a small improvement. Yes, use identical lengths in the cabling.

I made the mount myself using CM 1 1/4 mast, Fiberglass tubing (Max-Gain Systems), and CM roof mounts available at Lowe's. Everything is available at Lowe's or RS except the fiberglass: http://www.mgs4u.com/fiberglass-tube-rod.htm

PM me if you need more help.

jdspencer

12-14-04, 12:47 PM

Originally posted by jdspencer
Thanks for the input. I removed the RS amp, which is a two piece version, not a distribution amp. The result was no difference.

Interesting about the multipath, since at one time I had the antenna just 6 feet above the deck and was able to get 42. Moved the antenna higher and I lost it.

I guess I really need to get this thing above the roofline, especially since my house has steel siding. :) Here's an update.
http://www.avsforum.com/avs-vb/showthread.php?postid=4814258#post4814258

spinn74

12-15-04, 07:45 PM

I live in Mt Laurel, NJ about 18 miles from where the local HD channels are broadcasted. Does anybody have any suggestions of a good outdoor off-air antenna to use to receive my locals in HD? I am going to use a two way splitter also....will I need an amplifier because of this? Also any experiences with reception in this area?

jdspencer

12-15-04, 08:19 PM

First step is to go to www.antennaweb.org and check the direction of your towers and what frequencies they are using. Depending on the strength of the signals you may need an amplifier. Like it was in the 50's, getting the right antenna and a good signal is trial and error.

KBI

12-15-04, 08:28 PM

Will I need anything else to set it up on my Samsung 26inch HDTV??

KBI

12-15-04, 08:45 PM

Would I need a set-top box too? My TV already has a built in tuner?

HiggySlapBass

12-16-04, 12:36 AM

Antenna: Zenith Silver Sensor, you can get one at Sears.

Set-top box: As long as it's an ATSC tuner, you won't need anything extra.

Inundated

12-16-04, 01:15 PM

KBI doesn't say where he/she is located. Folks, please, at least give us the TV market you're in!

The reason I say that is because KBI may need a different antenna of some sort if he/she has VHF DT signals in the area, particularly in the lower end of the VHF dial. That doesn't mean the actual analog channel number is a low VHF, it means the digital transmitter is low VHF. The Silver Sensor, a stellar performer indoors, cannot pick up low-VHF digital stations at all...it's not designed to do so.

If the OP lives in the Chicago market, the CBS O&O station (WBBM/2) has its digital allocation on channel 3. In Grand Rapids, MI, one of the major stations is on a low VHF channel as well. And here in my home market (Cleveland/Akron, OH), the NBC affiliate, WKYC/3, has a DT channel of *2*.

Now, it's quite likely that KBI doesn't live in a market with low-VHF DT channels, but I thought they'd like to know. If you tell us where you're getting your TV from, city-wise, we'll be able to tell you.

http://www.antennaweb.org/ will also be helpful for YOU to find this information out yourself, and even get a street level map with bearings of the various digital (and analog) stations.

KBI

12-16-04, 02:15 PM

Bay area... San Jose, ca 40 miles from SF..

sebenste

12-16-04, 02:58 PM

Hello all,

I am using a ChannelMaster 4228 for OTA DTV reception 70 miles west
of Chicago, and it gives reasonably good results, given I have a CM
7777 preamp on it and the antenna is in an attic in a small river valley area.

My question is: Which is better: A CM 4228 8-bay UHF, or the DB-8 from
Antennas Direct? I have heard both do very well, but the DB-8 is of better
construction quality. The design on the DB-8 raises an eyebrow:
it has spaces inbetween the dipoles, indicating that: 1. it may not
reflect back signals as good as the 4228 and 2. It may not receive VHF-HI
(channels 7-13) as well as the CM 4228. I have also heard that the yagis
(corner reflectors) don't do as well, with the exception of the DB 91 from
Antennas Direct. My past experience with yagis isn't good in terms
of good reception. Their directionality isn't great, and thus, neither is
their gain.

Thoughts? Ramblings? Wish it were summer? :-)

ww2154

12-16-04, 08:32 PM

I am new to dish network and this might be a dumb question. I have the 811 receiver and hd package. I am wanting to receive ota networks using a outside antenna but want to use the same cable running from the outside dish . What do I need and where do I hook up the outside antenna.

Inundated

12-16-04, 08:41 PM

Originally posted by KBI
Bay area... San Jose, ca 40 miles from SF..

See, NOW I can help you :D

You have no low-band VHFs. You have the digital half of NBC O&O KNTV, right in your backyard, at DT 12, but you should be able to pick that up even with the Silver Sensor not being a VHF antenna (high VHF, plus the fact it's right now closer to you).

The San Francisco OTA stations could be a challenge to catch indoors, depending on where you are in the SJ area and what kind of line of sight you have towards Sutro.

Inundated

12-16-04, 08:43 PM

KBI - you might wanna post here for further help:

http://www.avsforum.com/avs-vb/showthread.php?s=&threadid=357896

This is the San Francisco(/San Jose/Oakland) local market thread, where you can get some help from people with familiarity with the Bay Area.

jimc705

12-17-04, 01:02 AM

2154

You will be needing a dipexer Channel Master and Winegard both make good ones. However a diplexer has a good deal of loss and unless you have fairly strong reception they may not work well. Give us your zip so we know where you are located in reference to the transmitters. If you can I would highly recommend using a seperate coax for the OTA antenna. Diplexers can cause sevral problems. Even Channel Master techs recommend running a seperate coax if possible.

Depending on your loaction and if you need a preamp or not will determine which type of diplexer may work for you.

dswallow

12-17-04, 02:39 AM

Originally posted by jimc705
2154

You will be needing a dipexer Channel Master and Winegard both make good ones. However a diplexer has a good deal of loss and unless you have fairly strong reception they may not work well. Give us your zip so we know where you are located in reference to the transmitters. If you can I would highly recommend using a seperate coax for the OTA antenna. Diplexers can cause sevral problems. Even Channel Master techs recommend running a seperate coax if possible.

Depending on your loaction and if you need a preamp or not will determine which type of diplexer may work for you.
Combined two diplexers might have 0.5db to 1db signal loss; very minor, really.

There can be issues diplexing an antenna signal, but the vast majority of people will be fine if everything is done correctly.

When an OTA signal can be provided over a separate cable, that'd be ideal, but you seem to be using a bit more "scare" in your post referring to diplexers than is really warranted.

sregener

12-17-04, 09:22 AM

Originally posted by sebenste
My question is: Which is better: A CM 4228 8-bay UHF, or the DB-8 from
Antennas Direct? I have heard both do very well, but the DB-8 is of better
construction quality. The design on the DB-8 raises an eyebrow:
it has spaces inbetween the dipoles, indicating that: 1. it may not
reflect back signals as good as the 4228 and 2. It may not receive VHF-HI
(channels 7-13) as well as the CM 4228. I have also heard that the yagis
(corner reflectors) don't do as well, with the exception of the DB 91 from
Antennas Direct. My past experience with yagis isn't good in terms
of good reception. Their directionality isn't great, and thus, neither is
their gain.

If you haven't read the review of the CM4228 at www.hdtvprimer.com yet, do so. It points out that the poor combiner design of the 4228 costs at least 2db of gain that theoretically should be there. The DB8 doesn't have the same problem, so there is probably some slightly better performance. He also states the benefit of the uniform reflective backing.

I've had a bunch of hybrid yagi/corner-reflectors (few people sell pure yagis anymore) and you have to understand how a yagi works. They are very directional at the frequency for which they're tuned. Usually, in the US, that means channel 69. As the frequency drops, the directionality drops as well. Now the 91XG has 28db of front-to-back ratio (at which channel, they don't say, so we'll assume it's channel 69,) which is very good. In comparison, the Winegard 9095P has a maximum of 14db. Obviously, the 91XG is better in this regard. But as gain increases, directionality increases *by default.* The more gain, the more directional. Period.

The problem for most people is that a large number of their channels are in the portion of the spectrum covered by the corner-reflector rather than the yagi in the hybrid. This occurs somewhere in the mid-30s. Below this point, the primary means of getting signal is on the corner-reflector portion of the antenna. Since you can get bounce from a wide angle and still hit the active elements, this reduces directionality a ton.

I think the DB8 is probably a fraction better than the 4228, and given your distance, you may want to try it. It also might perform adequately on hi-VHF for you, as all UHF antennas have *some* gain on hi-VHF, though you often need to aim the antenna off-axis for maximum signal.

maraldo

12-17-04, 11:56 AM

Hello. I am about 25 miles away from the Philadelphia towers and I am running an XG42 through a Sony ATSC tuner. I seem to be able to pick up all digital stations except for FOX (they are all clustered within 2 degrees of on another). Any suggestions. Thanks.

sebenste

12-17-04, 12:46 PM

Thanks for the CM 4228/DB-8 info. Now, what is the best 30 dB
preamplifier for under $100? I have the ChannelMaster 7777 now,
but I want even more gain with even less noise. OK, if it has to be over
$100, so be it. Prefer under $100 first.

Gilbert

jimc705

12-17-04, 12:48 PM

Sorry don't mean to scare anyone. The Channel Master diplexer has a pass thru db loss of .8 DB. Needing 2 that'll be 1.6 db loss. You can always amplify to get over line losses, diplexers, and splitters. However it's a lot cheper to keep the losses at a min.

This gentlemen looks to be a min of 40 miles from the tower to a max of 98. He's going to need all the signal he can get. A gain of 1.6 db may be the difference having dropouts every 30 second or so (unacceptable) or drop outs every 15 to 30 minutes which may be acceptable to some.

sregener

12-17-04, 02:35 PM

Originally posted by sebenste
Thanks for the CM 4228/DB-8 info. Now, what is the best 30 dB
preamplifier for under $100? I have the ChannelMaster 7777 now,
but I want even more gain with even less noise. OK, if it has to be over
$100, so be it. Prefer under $100 first.

You might be able to get less noise, but more amplification isn't desirable unless you've got the longest cable run known to man (think 500'+.) And the 7777 has some of the lowest noise figures I've seen quoted (2.0db.) I'd rate it as top notch.

Your preamplifier can't create signal where there isn't any. It can only amplify what the antenna is receiving. More isn't always better. Sometimes it's just more. Your best bet is to join two identical antennas together in a stack to increase gain, which will get you 3db of *real* gain. All a preamplifier with more db of gain is going to do is drain your wallet.

cpcat

12-17-04, 02:56 PM

My question is: Which is better: A CM 4228 8-bay UHF, or the DB-8 from

Sebenste,
The DB8 may be a little better, but at 70 miles you may need to stack like sregener mentioned. The problem with 8-bays is weight, windload, and they're very difficult to stack. You might consider a yagi/corner reflector like the Antennasdirect XG91 simply for the reason you can upgrade to a stack later if you feel you need more performance. Following is a pic of stacked yagi/corner reflectors which provide consistent reception over mountainous terrain at 65 miles:

And I agree completely that the 7777 is all you need.

Depending on your vhf needs (WBBM is ch. 3), you may have to add a separate VHF antenna mounted underneath similar to the pic. You'd need to have low-band capacity (the vhf in the pic is high-band only). If you want 3 only, I'd get a cut-channel 3. See http://www.starkelectronic.com/delhi.htm The VHF needs to be spaced 60 in. or so beneath the uhf section.

sebenste

12-17-04, 07:16 PM

Thanks, cpcat et al! Much appreciated. I can't get WBBM-DT 3, BTW...
even with a monster VHF in the attic (I don't own the roof of my townhouse), I can only get a 30% signal, and it takes 41% to lock on my tuner.

Gilbert

cpcat

12-17-04, 07:30 PM

Wow, I didn't read close enough to see you're in the attic. You are doing *very* well as is if you're receiving Chicago stations at 70 miles. In your attic, you don't really have the issues of the elements to deal with so you *could* consider stacking 2 8-bays, depending on how much room you have up there.

The 5 element channel 3 from Jerrold isn't actually that big for low band VHF and 7.5 dbd gain would give you a good chance from that distance if you were outside. All bets are off from inside the attic, though you seem to be doing well on the uhf side of things.

sebenste

12-18-04, 02:03 AM

Cpcat,

I took great care in putting this system together, talking with engineers,
looking and reading at various boards and how other dealt with their
issues. I have no room in the attic for a stacked array, horizontal or
vertical. I could replace the CM 4228 8-bay with a DB-8, but I would
like the VHF-HI reception when WLS and maybe WTTW go to channels 7 and 11 respectively for digital. Not saying they will, but rumors are 7
wants to go there when all is said and done. Can't say I blame them!

I have quad-shielded RG-6 for my 75 ohm cable run, and all my RG-6
cables are brand new quad-shielded from wall plate to DTV tuner,
DTV tuner to VCR, and VCR to TV. I can nuke my TV dinner in my nearby
kitchen and still watch WBBM-TV 2 analog without serious interference.
I am completely sold that the extra 3%+ of protection with quad
shielding helps give me my performance. My Winegard monster 16'
VHF-only antenna works very well, too. I can only get WBBM-DT maybe once a month. But...in September, I got WGBH-2 analog from Boston, MA
in E-skip right over WBBM...and a few weeks ago, I got KDFW-4 analog
from Dallas, all from my attic antenna in a low valley near a river 60 miles
west of Chicago. I also had an NBC on channel 3, possibly from
Florida...not sure, though. It wasn't from Madison, WI; it was E-skip, so
who knows what it was. Longest DT DX catch was in September, got
WSJV-DT FOX from South Bend, 160 miles away at 10 KW or some such
ridiculously low power.

Believe me, I can only imagine what I would get on the roof!

Gilbert

Rack

12-18-04, 08:52 AM

http://www.egrabow.com/gallery/ch3.htm
If it was an analog NBC 3, see if you can pick it out of the lineup here.

sregener

12-18-04, 09:02 AM

Originally posted by sebenste
My Winegard monster 16' VHF-only antenna works very well, too.

Is there some reason you won't be able to use this for channels 7 and 11?

cpcat

12-18-04, 09:55 AM

I have no room in the attic for a stacked array

I think you might just as well stay put, then. Again, the DB8 may be a small improvement, but it may not be significant to your overall reception.

My Winegard monster 16'

I'm confused, too, about why you can't use this for high vhf...and how you are combining the two with the 7777 and managing to get low band from the Winegard and high band off the 4228?

sebenste

12-18-04, 08:45 PM

Hey guys,

Sorry to confuse you. I'd rather keep it simple up in the attic. I use
the CM 7777 as a diplexer, with the monster VHF Winegard hooked
up to the VHF connector, and the UHF to the UHF connector. But, if I
can get 7-13 off of the 8-bay CM 4228 UHF, then I can use the
Winegard to either point northwest towards Madison, WI, or south
to pick up a station 35 miles south of me.

I agree that I think I'm doing about as well as I can, and a DB-8, from
what it sounds like, may only help marginally. But, I wanted more
opinions, in case I was missing something.

Incidentally, a friend of mine has an HDTV and the biggest Winegard
VHF/UHF combo they make on an outdoor 30' tower, about 60 miles west
southwest of Chicago. He's south of a ridge that really prevents me from
getting any DX from the south or southeast. In any case, using a 20 dB
gain preamp, he can get the higher power WTVO-DT from Rockford
which is northwest of his location by about 35 miles, but none of the
others on lower power STA's. He can, however, get channels 3 and 12
from Champaign, and all of the Quad Cities/Moline IL TV stations over
100 miles away. I coached his setup and he's doing better than I am
by a mile. Oh, to have an antenna like that on a 30' tower! But I will
stop drooling now. ;-) DXing with his setup is fun!

BTW, I use a Zenith HDV420 to pick up the stations to my lousy
TV. I get a 90% or so on WGN-DT, 70% on WLS-DT, WFLD-DT;
an 80% on WYCC-DT with 99 "whopping" KW of juice, and
80% on WPWR-DT. The others are lower power and around 50%.
As a reference, to lock a station, you need a 41% signal to see it
reliably.

The hardest one besides WBBM is WCIU-DT, at 1 KW transmitter power
output and 15.1 KW ERP from Sears Tower. I can get that station
consistently about 1 day a week, otherwise it always breaks up.
But at 15 KW, I think I'm still doing good with my setup. A guy who
has a very similar setup to mine 1 mile east of me in a taller attic
using a CM 4228 UHF and CM 7777 preamp gets WCIU with 60%
consistently. His dad just retired as a chief engineer of a TV station,
so naturally I have been asking him lots of questions. He even built
*his own channel 3 antenna*, bigger and better than what you can buy,
and he gets it from his attic, also 60 miles away, essentially, and in the same low-lying area of the river valley. I'll wait until WBBM heads for
a UHF allocation, though, as I have no desire to try to build my own
monster antenna. Hey, that sounds like it could be a hit Discovery
Channel show for us HDTV and antenna weenies! :-)