# Great OTA signal, picture & sound breakup still



## ravedog (Apr 23, 2003)

*Unit:* HR10-250
*Soft Ver:* 3.1.5f01-2-357
*Antenna:* Large roof antenna mounted in attic (damn HOA rules) via 25' RG-6 cable direct into back of unit via Ant RF connector.
*Location:* 89117 (Las Vegas, NV)
*Distance to Xmitters:* approx 17-18 miles, all line-of-site, no obstructions.
*Time in service:* approx 15 months (2 weeks ago, COMPLETELY wiped and reset and reprogrammed (UGGGH!) because Season Pass manager was painfully slow.

*Signal Strength:* Out of all the channels I care about, mainly the networks and PBS, I am getting a MINIMUM of 92-92 on both tuners' signal meter. Awesome!!! Occasionally, you'll see the signal drift on one tuner from 91-92, but otherwise stable.

*Problem:* _The following problems only occur on programming received thru the OTA tuners and often with HD programming. Sat reception is not an issue._ You can see that I have excellent strenght on both tuners, etc. but the problem is that whether I am watching live tv or Tivo's material, I get audio breakup and video pixelation. Sometimes its as frequent as 1-2 times a minute sometimes less. NBC (3.1) is the biggest offender, but i get a lot on ABC (13.1) and FOX (5.1, not shown in graphic... strange) as well.

We have experienced digital breakup before but very rarely. The problems seem to be multiplying to the point where some programming is unwatchable (like watching _Kidnapped_ the other night). Nothing has changed with the installation or cabling.

I have read on here people's varying experiences with cracking open the box and going direct to the Tuners, but i seem to be getting about as good-a-signal as one can hope for.

Any ideers???


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## litzdog911 (Oct 18, 2002)

You might actually have TOO MUCH signal. The HR10-250's ATSC tuners are easily overloaded. Try inserting one of these in the antenna cable and see if it helps ....
http://www.radioshack.com/product/i...kw=attenuator&kw=attenuator&parentPage=search


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## ravedog (Apr 23, 2003)

I will try that out tomorrow and see how it performs for a few days and report back here. Thanx for the suggestion...


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## bradfjoh (Oct 19, 2005)

just out of curiousity... Why would ravedog be getting too much signal all of a sudden? Wouldn't this have been an issue since the beginning or is it common for networks to adjust their signals etc thus causing havoc for those of us using OTA???


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## tucsonbill (Aug 11, 2004)

ravedog said:


> I have read on here people's varying experiences with cracking open the box and going direct to the Tuners, but i seem to be getting about as good-a-signal as one can hope for.
> 
> Any ideers???




You mentioned that your antenna is large so I'm assuming it's some vhf/uhf model. Your three worst offenders are all in the VHF band, the worst being on channel 2. They all have at least two subchannels. They're all running low power (a worse problem because they're vhf) Although channel DT channel 5 is a pretty respectable 86kw, compared to the 16kw of the others. It's a shame that you can't get the antenna out of the attic. It might help. It might help to re-aim it. The biggest help for all of us will be when they go to full power.
My local DT channel 13 just added another subchannel. Now CSI Miami is prone to beakups again, even though like you I show90-92%. (The sports fanatics, tell me HD on this channel is almost unwatchable on fast action.) You can try the attenuator, but with all respect to litzdog (who is a very knowledgeable guy) I've long discounted the too strong signal as HD TiVo legend. I simply don't believe that any modern design rf front end is going to be overloaded by a 16Kw xmitter 18 miles away. If you're interested, the info on trasmitter power can be found here.

I just looked back and saw that you say the problem has worsened recently. You might look at  this thread over at AVS and see what experience other viewers are in LV are having. In addition to low power a lot of the stations are still learning the technology and strange things happen from time to time. At least you know if you experience is unique there might be some cause outside your control.


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## pmezzo (Sep 29, 2006)

ravedog said:


> *Unit:* HR10-250
> *Soft Ver:* 3.1.5f01-2-357
> *Antenna:* Large roof antenna mounted in attic (damn HOA rules) via 25' RG-6 cable direct into back of unit via Ant RF connector.
> *Location:* 89117 (Las Vegas, NV)
> ...


I think what you may be experiencing is multipath. This comes from the signal bouncing off objects such as buildings, mountains etc. This causes the signal to be received at slightly different times which degrades the "quality" not the "quantity" (IE signal strength) of the signal. The best way I found to fix this is to use a highly directional antenna. This will usually work provided all the transmitters are coming from the same direction.


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## Sir_winealot (Nov 18, 2000)

We had a similar problem recently ...where prior to that, there was none.

Even though the signal was still strong, it seemed that throughout the summer, there had been so much tree growth that it affected the picture in the same way as you describe.

By moving the antenna (also in the attic) several feet, the problem disappeared.


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## HomieG (Feb 17, 2003)

bradfjoh said:


> just out of curiousity... Why would ravedog be getting too much signal all of a sudden? Wouldn't this have been an issue since the beginning or is it common for networks to adjust their signals etc thus causing havoc for those of us using OTA???


A few reasons beyond his installation or control:
- Stations increased transmission power and/or antenna gain
- Stations re-oriented antennas
- Signals bounce off of buildings, houses, etc. and something close-by may have changed to now put the OP in either a multipath or stronger signal profile.
- And, believe it or not <sigh>, digital transmissions are not perfect and TV stations and networks do have glitches.

If it were me, I'd first do what others here have suggested...try moving the antenna a few feet.


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## ravedog (Apr 23, 2003)

I have an update for all those who helped me out:

*What I've done since last visit* 
I hooked up a spare 24" Samsung HDTV to an external Samsung HDTV Tuner box to the same antenna that was feeding the HD DirecTV Tivo, using a basic splitter and some RG-6. Set both the DirecTV Tivo on OTA Channel 3-1 and the Samsung HDTV Tuner box to the same channel, watching both TV's at the same time. Result: Both exhibited the same artifacting at the same times on channel 3. When conducting the same experiment on other channels: no problems. So this seemed to be beyond being a problem with the DirecTV receiving too hot a signal (unless the Samsung external tuner was just as bad a receiver... what are the odds).

litzdog911 mentioned I should try a Radio Shack attenuator, but no stores in my area nor the online site still carried it (or maybe it was out of stock). So I tried another route:

After pouring over the 128+ page thread over on _AVS forums_ (thanks tusconbill), regarding issues in Vegas, I discovered that there were a few others having problems with KVBC as well. So I took this info and got in contact with KVBC chief engineer who actually asked me to call him within 3 hours of sending him an email. (When in doubt, goto the source).

I relayed what I had explained here and he was curious if I had any motors nearby or if i were in the airports flightpath. Yes to an A/C motor (turned out not to be an issue) and no to the airport. By the time I got to this conversation with him, I hadn't had any problems with channel 3-1 for over a week, so he asked me to do an experiment: watch channel 3 live one night, digital on one monitor and analog on the other (fun with the delays). We wanted to see if when there was artifacting on digital, to see if i got ANY noise on the analog TV (ruling out interference?) Over 2 nights I tried the experiment and it failed as there was no breakup on either night. Seemed like the problem had gone. _(It always works for the repairman)._

Since I had his ear, I asked him why we only had issues with their channel and none of the other locals, he told me that it was the part of the spectrum (the fact that they were on VHF low). I then asked why FOX who was on channel 5 didn't suffer the same issues, to which he responded that FOX was actually a lot higher up when it came to digital.

The next day we spoke again and he had told me that they were experiencing problems with the Digital transmission pipe for a few weeks (that makes sense) and about 10 days ago, they rebooted the whole digital feed system (in a manner of speaking). This happened on a Wednesday. Coincidentally, from that Wednesday night onward, we haven't experienced any problems (or maybe 1 glitch per night, compared to 100's). So far we have gone about 12 days since a problem. Here's hoping that it was in fact, on their end.

Thanx to everyone for the help.


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## TyroneShoes (Sep 6, 2004)

pmezzo said:


> I think what you may be experiencing is multipath...





litzdog911 said:


> You might actually have TOO MUCH signal...


If either of those were the case, that would cause the signal quality reading to go down. 90-92 indicates not only a proper amount of signal, but that it is being minimally interfered with. The SQR does not indicate raw carrier signal strength, but the ratio of successfully decoded bit to unsucessfully decoded bits. As such, too much (or too little) signal or too much interference will cause this reading to be much lower. If there is breakup along with continuously good SQR readings, it usually indicates problems at the transmission source or problems playing files back from the HDD, and it also typically indicates that the reception and decoding is NOT the issue.


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