[ttodd1]

OK, I have read and read and I think I am just making myself nuts. :grin:

Attached is a print out of my location from tvfool.com.

I am having major pixilation issues on the WIS station. Some minor issues on the WOLO station. WIS signal bounces from 80s to 0 alot - both tuners. WOLO has a pretty steady 30-35 signal and has less problems. I have tried the not having sat channels on MPEG-4 but still have problems. The rest come in fine - so far. I have a DB4 antenna in my attic and a HR20-100.

Could someone take pity on me and confirm/deny/correct me in this issue?

 

[houskamp]

Jumping around is usualy multipass issue.. have you tried turning your ant? even a few degrees my fix it..

 

[jdspencer]

If it was a bad receiver then you'd see problems with the sat channels as well. Having the antenna in the attic will attenuate the signal, which will increase the multipath problem. Besides changing the direction of the antenna, moving it in the attic may help. But, having it high outside is the best bet.

 

[ttodd1]

I agree but there are reasons why it is not outside. The thing is the signal was not bad before. Picture on the OTAs was good, no pixilation (well maybe the occasional spot) but over the last month or so it has just gotten pretty much unwatchable. My LOS has not changed. That made me wonder if it was the box. Also couldn't just the OTA tuner(s) go 'bad' and the sat ones stay fine? I'm going to try adjusting the antenna this weekend and see if it will clear up.

 

[David MacLeod]

is it possible that the local transmitter has changed it power?

 

[hasan]

I agree but there are reasons why it is not outside. The thing is the signal was not bad before. Picture on the OTAs was good, no pixilation (well maybe the occasional spot) but over the last month or so it has just gotten pretty much unwatchable. My LOS has not changed. That made me wonder if it was the box. Also couldn't just the OTA tuner(s) go 'bad' and the sat ones stay fine? I'm going to try adjusting the antenna this weekend and see if it will clear up.

Yes, the tuners (ota) could go bad, and not affect the sat, so that piece of troubleshooting advice is ...well...wrong.

What you are seeing, however, does have all the symptoms of multi-path. The antenna you are using is VERY broad off the front, and doesn't have a very good front to back ratio, so if there are reflections in your area, that antenna will not do a very good job discriminating against them. Since you have some stations that aren't doing this, it pretty well points in that direction (short of something funny going on at the transmitter). The fact that you get occasional pixellation on your HDTV's tuner, indicates the same thing, it just may be doing a better job.

Are you using the AM21 with an HR21 or are you using the HR20 series? The AM21 does much better with multi-path than the HR20 series, but even it is subject to severe problems.

If there has been any new construction of any size adjacent to the signal path, you could be getting multi-path that wasn't there before.

Try turning the antenna and see if you can eliminate it. Otherwise, go to a more discriminating antenna like the XG-9 series at solidsignal.com, which does an excellent job of discriminating against multi-path (UHF only).

 

[bdcottle]

I will have to agree with houskamp. Jumping around is usually multipath issue. Turning the ant a few degrees will usually help. But a few things first.
Check your cable ends.
Make sure you are pointing the correct end of the antenna at the transmitter. It's not the end you would expect it to be. Most antennas look like an arrow and the tip of the arrow points away from the transmitter. What I always think of as the back end of the antenna points at the transmitter.
To find the transmitters in your area I use http://www.antennaweb.org
I have also found this Amplifier to be a big help.
http://www.partstore.com/Part/Thomson/RCA/VH121.aspx?s=froogle

 

[bakers12]

The DB4 antenna the OP is using is not the arrow-shaped type. It has 4 bow-ties in front of a mesh reflector. The bow ties are the "front" which face the transmitters. The mesh faces away.

Since it's probably multipath causing problems, an amplifier will usually amplify the trouble as well.

 

[houskamp]

I agree but there are reasons why it is not outside. The thing is the signal was not bad before. Picture on the OTAs was good, no pixilation (well maybe the occasional spot) but over the last month or so it has just gotten pretty much unwatchable. My LOS has not changed. That made me wonder if it was the box. Also couldn't just the OTA tuner(s) go 'bad' and the sat ones stay fine? I'm going to try adjusting the antenna this weekend and see if it will clear up.

With my antenna setup I can't get both a good analog AND digital signal at the same time.. If I get one perfect the other will be bad.. Make sure you adjust the antenna with the signal meters on the reciever you care about..

 

[Kansas Zephyr]

Remember, if your TV has a digital tuner, you can always feed it the OTA antenna to verify reception.

Then you'll have another baseline to check signal strength and stability.

 

[ttodd1]

With my antenna setup I can't get both a good analog AND digital signal at the same time.. If I get one perfect the other will be bad.. Make sure you adjust the antenna with the signal meters on the reciever you care about..

I am only using the antenna to get HD. DTV has my locals just not in HD - yet....

 

[ttodd1]

Remember, if your TV has a digital tuner, you can always feed it the OTA antenna to verify reception.

Then you'll have another baseline to check signal strength and stability.

I just thought of that this AM - what you forget you have when you get focused on 1 thing....

 

[ttodd1]

Well I spent most of this afternoon trying to "play" with this. I hooked the antenna to my TV and got it to where the channels came in crystal clear. Hooked it back up to the HR20 and it still has some issues. I have continued to 'tweak' it and I think I can get to a point where it is at least watchable (at least more than it was). I have for the most part 'lost' my ABC station (it is on the high VHF band and since the DB4 is a UHF antenna I guess this is to be expected as I did not have a very strong signal from them to start with.) I am making a jump as to say that the OTA tuners on the HR20 are just too finicky.

I am looking at other antennas, but if anyone has any other suggestions....

 

[TomCat]

The $60 Channel Master 4228 is a somewhat better antenna, and probably the best you can get for DT. It is branded as a UHF antenna, but also works quite well for 7-13. If none of your locals are in 2-6 or will move to 2-6 (unlikely) this antenna might help. It is better than the DB8, and that is better than the DB4. At 23 miles through the attic, a stronger, more directional antenna such as the CM4228 is probably in order. Be sure you have no metalized insulation in the attic that is blocking/reflecting signal.

The HR20 tuners are actually better than many tuners out there, but I agree that the AM21 may also help, as it seems to be better than the HR20.

I think we have a consensus on multipath here. Better antennae and better tuners are the two ways to target that.

 

[TheJERK]

Wow I'm glad I found this post. My HR-20 100 has a problem with just one channel doing this. I am using an HR20-100 with a DB8 antenna in the attic. I'll try moving it outside this spring when I have the chance.