OTA Reception Nightmares!

[jdag]

I am having a real tough time getting consistent reception with an off-air antenna. I suffer frequent pixelation and freezing, particularly on my CBS affiliate. I've tried different cables, cable lengths, with/without filters, and antennas (both in-house and outdoor). Currently I have both of these models:

http://www.solidsignal.com/prod_display.asp?PROD=AD-DB2
http://www.solidsignal.com/prod_display.asp?PROD=AD-DB4 (mounted on roof, about 100' of cable)

Today I fiddled with the DB2 model, using a 10' coax cable and just trying different positions and locations in my living room.

Using the meter on my DirecTV TiVo receiver, I found that the best location was about 4' from my television, pointing toward my back window. I simply set the antenna on a chair. In the best case my reading was about 70, but at least it was stable and gave me a stable picture. Normally on this particular channel my readings jump between 0 and 70.

But, move the antenna closer to the windows and the signal meter dropped substantially, generally down to 10-20. If I used a longer cable and tried going upstairs, outside, etc. the signal dropped.

Any thoughts? I am really pulling my hair out!

Thanks, John

[litzdog911]

John, you haven't given us any information about where you're located or how far away the TV transmitters are. Check out these resources for the best OTA antenna advice specific to your location ....

* http://www.antennaweb.org
* "Local HDTV Reception Forum" at http://www.avsforum.com. Find the thread for your nearest city and see what antennas work best for folks in your area.

[jdag]

John, you haven't given us any information about where you're located or how far away the TV transmitters are. Check out these resources for the best OTA antenna advice specific to your location ....

* http://www.antennaweb.org
* "Local HDTV Reception Forum" at http://www.avsforum.com. Find the thread for your nearest city and see what antennas work best for folks in your area.

I realize the info I provided was sketcht, but my biggest question is why a move of a few feet, when pointing the antena in the same direction, could make such a difference. Then just "plopping" it on the chair works perfectly.

I am in Rochester, NY and have used antennaweb in the past.

[JimSpence]

I had my somewhat larger antenna mounted on the roof and couldn't get digital channel 7 to come in. The thing was pointed at my neighbor's tree. I thought that VHF could get through a somewhat sparce tree. But, the multipathing was awful. I moved the antenna north about 20' along the roof. Everything works fine now.

[WinstonSmith]

Mine was awful tonight, too, on my local CBS affiliate here in STL.

Problem is that one of my tuners is upper 60s tonight and the other is about 25.

I wish there was a way to select which tuner would record which channel.

[MoInSTL]

I am having a real tough time getting consistent reception with an off-air antenna. I suffer frequent pixelation and freezing, particularly on my CBS affiliate. I've tried different cables, cable lengths, with/without filters, and antennas (both in-house and outdoor). Currently I have both of these models:

http://www.solidsignal.com/prod_display.asp?PROD=AD-DB2
http://www.solidsignal.com/prod_display.asp?PROD=AD-DB4 (mounted on roof, about 100' of cable)

Today I fiddled with the DB2 model, using a 10' coax cable and just trying different positions and locations in my living room.

Using the meter on my DirecTV TiVo receiver, I found that the best location was about 4' from my television, pointing toward my back window. I simply set the antenna on a chair. In the best case my reading was about 70, but at least it was stable and gave me a stable picture. Normally on this particular channel my readings jump between 0 and 70.

But, move the antenna closer to the windows and the signal meter dropped substantially, generally down to 10-20. If I used a longer cable and tried going upstairs, outside, etc. the signal dropped.

Any thoughts? I am really pulling my hair out!

Thanks, John

Is the jump from 0-70 a one time thing or does it fluctuate a lot? If it does it is multipath issues which can be tough to resolve. I know because I have a giant evergreeen next door that blocks my direction for OTA. I had the DB2 and have the DB4 now in my living room. When it was on the roof I found that a very slight tilt up helped. Try a 3-5 degree tilt and see it that helps. Try tuning in CBS first and then the others. It's a long process sometimes and can be vey frustrating to pull them all. I'm in the same boat and it can take some time.

FWIW, when it was on the roof I added a 3 foot extension onto the mast and that made a big difference. Granted it was just a tad higher but in the same spot.

[nclou]

I think I'm about to ditch the Tivo over this OTA reception. When my TV was in the living room, I picked up everything with a basic set top antenna. Since I moved the TV 60 feet away to the family room, I can't get everything at the same time.

I've gone through 5 progressively stronger antennas without success. I'm just not going to buy and pay for installation of a rooftop antenna for this Tivo. I like Tivo, but I'm not obsessive about it.

I was already to open it up an try to replace the cables inside, and then start buying attenuators and so on, but it's all becoming more aggravation (and cost as each little thing adds up) than it's worth.

My locals are on the sat, so I'm trying to work a deal for an HR20.

[WinstonSmith]

Have you tried doing anything with the internal tuners? Meaning, have you checked out the thread about trying to improve signal strength?

[TyroneShoes]

I...my biggest question is why a move of a few feet, when pointing the antena in the same direction, could make such a difference. Then just "plopping" it on the chair works perfectly...
Multipath interference is the nemesis of digital reception, although it doesn't really affect analog reception in such a negative manner, making the strategies for digital reception significantly different for DT than NTSC.

If you have multipath interference (and it sure sounds that way) rough terrain and/or physical obstacles will cause nodes of constructive and destructive interference. This means that the ratio of desired to undesired signal (on the same frequency from the same source, any reflected or delayed signal being undesired) may change dramatically from one physical location to another, even a few feet different. In a negative node the ratio can be above the threshold that prevents the tuner from working, while at a positive node the ratio can be below that threshold, and reception is then OK.

You need a DB8 or a CM 4228 (preferable), mast-mounted. IOW, a highly directional antenna with the best direct line of sight possible.

[FlugPoP]

What kind of cable are you using on the 100ft run? Is it possible to reduce that amout of cable(loss of signal)? Also are all you connectors crimped right sometimes a bad connetor can allow mulitpath into your cable and cause problems. Just some thoughts.

I am 36(line of site) miles from my local stations and my directivo gets just as good or better than my Sony HD100 did.