I hope someone will actually find some difference in the signals from the good and bad exciter. I called Dish today, to let them know of my experience. I realize I'm just circumventing the problem with attenuation, but I wanted to let them know about the band-aid just in case it gives them a clue to what is going on.
622 OTA signal loss
- Thread starter barrysb
- Start date
- Latest activity Latest activity:
- Replies 111
- Views 22K
I hope someone will actually find some difference in the signals from the good and bad exciter. I called Dish today, to let them know of my experience. I realize I'm just circumventing the problem with attenuation, but I wanted to let them know about the band-aid just in case it gives them a clue to what is going on.
Since the transmitter manufacturer is aware or the problem and the reason for it and the receivers affected, don't you think that they will be working with E* and D* to find out where the real problem lies? I would think that they would want to get it solved as badly as we do.
I'm not sure about anything at this point. AFAIK, much of the receiver technology is centered around an ATSC chip that has gone through about 5 generations to date. If this condition is inherent in one of the earlier generations and that is the one used in the 622, then hope for a solution with existing hardware could be a problem.
Sorry, lost track of this thread. Hope this doesn't get too long winded.
The 942 had a "problem" in that it used to put out DC voltage to the OTA antenna. Same thing as a preamp (ex: cm7775). Depending on how you had your antenna cabling configured some of us thought this extra voltage was causing a problem. Radio shack at the time had a simple device that you would screw into the coax connector for the OTA antenna on the 942. (Looked similar to a non adjustible attenuator, just a little shorter). As far as I know, this DC voltage shouldn't be an issue with the 622. But as the DC Blocker did no harm to the signal I continued to use it when I hooked up my 622.
After the windstorms my signal on all channels (except KCPQ) improved. KCPQ actually dropped a couple of points on the 622 signal meter (btwn 65 and 68). Although I wasn't seeing picture breakup. Just for grins I removed the DC blocker. The result was that the max signal looked about the same but I noticed on the meter that the signal dropped to zero (although I didn't lose picture). I put the DC Blocker back on and no longer saw drops to zero. So I don't know if this addresses the specific issues which this thread brought up, but it seemed to work in my case.
I checked the Radio Shack website and could not find the product. Might be they don't carry it anymore. My local store closed so I can't just run down there. But if you do a web search on DC Blocker you should be able to find something somewhere. They should only cost a couple of bucks. It basically looks like a little metal tube (approx 3/4 of an inch long) with the appropriate male/female coax connectors on either end.
I wish I could believe this. I bet Dish will say anything to fool the customer into thinking everything wll be fine/get them off the phone, while in reality they sit and do nothing.
My Vip211 is certainly affected on my local FOX (KXTV) and ABC (KTXL). My 6000 never had this problem. As soon as I got a 211 these OTA channels went to sh*t. Same antenna, same wiring. The signal strengths are 90%, then they just drop to zero for a split second. This results in anything from pixellation, dropped frames, and Lost Signal Error screen.
Hammer
I know large value attenuators are not readily available, but I hope someone else will be able to try my band-aid work-around for this problem, just to see if it helps their situation. In case anyone is interested, here's a source.
Chuck: thanks for the details on the DC blocker. My signal on KCPQ, too, has dropped into the 68-70 range (formerly 72-75) and that's getting just a little bit close to where I start to lose it. The drops-to-zero are still happening, though less frequently. I appreciate the info and for a few bucks, it can't hurt and maybe will help...
Tried it for a week- DC Blocker not working for me. Still having problems with two OTA locals on my 211 dropping to zero frequently.
I give up! Since Dish wont fix this, I have decided to buy yet another (makes 4 in this house) OTA HD tuner for my main viewing Tv. Using others for recording and other rooms. Have to just abandon the 211 OTA tuner for FOX & ABC- UNWATCHABLE.
Hammer
It would be interesting to know if a large amount of attenuation would fix your problem. 20dB works for me.
Here's a source
I'll try it, I've got one of those too.
Note: I just found out my local FOX & ABC do NOT even use the Axera exiter, that supposedly Dish is working with to resolve... ya right.
Could it be a broader issue like 622/211 has problems with 720p streams?
Hammer
Note: I just found out my local FOX & ABC do NOT even use the Axera exiter, that supposedly Dish is working with to resolve... ya right.
Could it be a broader issue like 622/211 has problems with 720p streams?
Hammer
Who knows, but my problem local station is a NBC affiliate and broadcasts 1080i.
Was it a temporary solution?
KCVU FOX 30 here in DMA 130 was working great until a few days ago when the dreaded Axcera Exciter symptoms returned to the airwaves. The Sunday before I noticed that the channel went off the air for a while, returned to low power for a while, then returned to full power. I didn't notice any problems until a couple of days later. This time the problem now extends to my TC32LE60 and all my ViP622's. I contacted the station and was informed that, to the best of the engineers knowledge, nothing had been changed since they got the fix from the exciter company. I suspect that maybe the firmware got corrupted, or was upgraded and is now introduces problems extending to other receivers.
Other out there having problems again?
KCVU FOX 30 here in DMA 130 was working great until a few days ago when the dreaded Axcera Exciter symptoms returned to the airwaves. The Sunday before I noticed that the channel went off the air for a while, returned to low power for a while, then returned to full power. I didn't notice any problems until a couple of days later. This time the problem now extends to my TC32LE60 and all my ViP622's. I contacted the station and was informed that, to the best of the engineers knowledge, nothing had been changed since they got the fix from the exciter company. I suspect that maybe the firmware got corrupted, or was upgraded and is now introduces problems extending to other receivers.
Other out there having problems again?
I'm not in this DMA, but have had similar problems with one of my local stations. The engineers at this station claim the intermittent signal loss reported by my 622 has nothing to do with their signal.
I'm hoping that someone out there, who definitely knows their reception problem is due to exciter firmware, will try my work-around of using a large attenuator to reduce the signal input to the 622 to the low 70s. If it works, it just might give the engineers a clue as to what is causing the problem.
Barrysb,
I've tried varied attenuation and different antenna configurations/cabling. Nothing helps here! I really get a kick out of the stations saying that it is a problem at our end. This is not the case here, but the station at first blamed my equipment. I think it is about time that those responsible for the advent of this digital transition police not only the airwaves but the manufactures of the digital product to kill these frustrating bugs. Regarding the 622, the ATSC tuner is inflexible as compared to many other ATSC tuners. It wouldn't hurt if some efforts were put into making them more flexible so they will work with a less than perfect signal.
boy921
There have been at least five iterations of ATSC tuner chips developed since the inception of DTV, each one an improvement over the other. It appears the chip in the 622 is not the latest and greatest version. It's up to Dish to start using the latest generation in their hardware. This won't help us but there is hope for the future.
BTW, how much attenuation did you try? I had to use 21dB and the picture still occasionally pixelates, but certainly watchable. In my case, I didn't see much improvement until I hit the -20dB mark.
We are still clean and clear on WHBQ FOX13 in Memphis. I recorded 24 this week and it is clear, both audio and video. I think that your assumptions are probably correct. Our FOX engineer is a frequent contributor to the Memphis forum on the AVS HDTV forum and is very good to work with. He even went to one of the homes having trouble to work out the exciter problem.
barrysb,
I hope this will refresh your memory as you previously asked and I answered.
boy921 post #17 said:
If by adding attenuation will help eliminate the out-of-phase signal that is interfering with the regular signal, and attenuation will not degrade the regular signal significantly, then I can see where multi-path is correctable. The problem here is not multi-path. From your previous posts it seems that this is somewhat helpful for you. Adding the attenuation in your case is tricking your receiver so it operates normally with a an other than mauti-path problimatic signal? From what I understand, future generation ATSC tuners will be capable of negating the effects of multi-path.
Of the "five iterations of ATSC tuner chips developed since the inception of DTV" why are first generation chips not having problems as the newer ones? And it would be interesting to know just what generation ATSC tuner is used in the ViP.
boy921
dogpoobob,
Do you know if the Memphis stations exciters are now equipped with a newer version firmware upgrade that is higher than the version that was causing the problems? Or is it possible that you could find out what version they are currently using?
Thanks,
boy921
Even though attenuation helps in my case, I don't believe it's because of hiding multipath signal errors. My analog reception of channels near the problem channel are very nearly ghost free. Some of these channels are coming from the same tower as the problem channel. I could be having a problem with errors caused by an out-of-market signal, either adjacent or co-located, but I haven't been able to identify the station. And, I guess, it still could be related to some error in the transmitted signal, but it is difficult to come up with a good reason why attenuation would affect this condition.
So I'm still in the dark except I have a work-around. However, it's a pain to switch the attenuation in or out particularly for unattended recordings.
