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Channel Master CM-7000 Digital to Analog Converter - Page 42

post #1231 of 1483
Quote:
Originally Posted by slprp1 View Post

The channels are limited to begin with and I was receiving WLIW (channel 21), which is a local PBS affiliate. I had been receiving it well all along and now have lost it completely as of 6/12! Nothing has changed with my setup. Yes......I've tried re-scanning (10 times already).

ask here (NYC OTA thread):
http://www.avsforum.com/avs-vb/showt...9&goto=newpost

you will have to give them more details, like your TVFool.com data and which kind of antenna you have (indoor/outdoor). lots of people have lost WLIW, ABC, CW and Thirteen. in my case, i can get Thirteen better (about 70%) if i place my antenna in the middle of the kitchen, 8" off the floor, facing a particular direction. istill have a hard time to receive ABC and CW. and have never received WLIW over the air.

basically, you will need to search for a "sweet spot" in your home. it might be under a bed, inside an oven, on the top of the fridge or any other inconvenient place like that.
post #1232 of 1483
Quote:
Originally Posted by vwoom View Post

Update: My "crisp" new CM is displaying a somewhat odd behavior lately when I tune to Los Angeles NBC Plus 4.2 WX+NR, supposedly in 480i...whenever the US weather map is displayed.

More than once on a daily basis, the CM somehow displays this channel so blurry (picture it like you need real strong prescriptions..)...akin to the resolution of a real bad copy of a VHS PQ re-copied recording I can remember...I call it the "180i" bug.

However, once I jump to another channel..say down to NBC4LA 4.1 or up to NBC-Universal Sports 4.3 and then back to 4.2, the blurred PQ goes away...

Does anyone else in Los Angeles with a CM having this kind of buggy tuning on 4.2? How about any other CM owners out there...any similar quirk observed in your units on certain channels, similar to what mine does?

A fix perhaps or explanation to this bug would be greatly appreciated.

Thanks for the replies...I know this bug ain't a biggie, but it's a little annoying. Yesterday, I found out that the CM blurry "bug" is not isolated to the 4.2 WX+NR channel.

On two occassions, this blurry PQ was also present while switching between subchannel 480i KCET-OC 28.2 and main 720p KCET-HD 28.1...though not as bad as the WX (like watching with cataracts).

Regardless of this slight annoyance, I still prefer the overall superb PQ enjoyment of the CM compared to that of the Zen DTT901 (thoroughly blurry/"180i bug" free...).
post #1233 of 1483
Quote:
Originally Posted by vwoom View Post

Thanks for the replies...I know this bug ain't a biggie, but it's a little annoying. Yesterday, I found out that the CM blurry "bug" is not isolated to the 4.2 WX+NR channel.

On two occassions, this blurry PQ was also present while switching between subchannel 480i KCET-OC 28.2 and main 720p KCET-HD 28.1...though not as bad as the WX (like watching with cataracts).

Regardless of this slight annoyance, I still prefer the overall superb PQ enjoyment of the CM compared to that of the Zen DTT901 (thoroughly blurry/"180i bug" free...).

Same here in D/FW: Ch 5/NBC and their weather sub. Oddly enough I don't recall seeing it on Ch 8/ABC-subs.
post #1234 of 1483
Quote:
Originally Posted by nordloewelabs View Post

ask here (NYC OTA thread):
http://www.avsforum.com/avs-vb/showt...9&goto=newpost

you will have to give them more details, like your TVFool.com data and which kind of antenna you have (indoor/outdoor). lots of people have lost WLIW, ABC, CW and Thirteen. in my case, i can get Thirteen better (about 70%) if i place my antenna in the middle of the kitchen, 8" off the floor, facing a particular direction. istill have a hard time to receive ABC and CW. and have never received WLIW over the air.

basically, you will need to search for a "sweet spot" in your home. it might be under a bed, inside an oven, on the top of the fridge or any other inconvenient place like that.

Thanks (to all, so far) for the replies!

My primary issue is that......I was receiving WLIW-21 the day prior to the transition (and for over a year prior to that).
Why should I need to move or upgrade my antenna?
The signal is originating from the same transmitter and the signal is supposed to be stronger!......Where's the justification?......Why did I lose the signal completely?......It simply makes no sense (to me at least)!
post #1235 of 1483
Quote:
Originally Posted by slprp1 View Post

...Why did I lose the signal completely?......It simply makes no sense (to me at least)!

Probably because of changes on the day of transition.
Try following the links to the local OTA thread posted earlier.
post #1236 of 1483
I'm looking to swap my Apex DT502 for a CM-7000 if anyone is interested.
post #1237 of 1483
I tried to swap a CM-7000 for a DTVPAL Plus and got no takers, I already have a DT502 sorry.

Philip
post #1238 of 1483
For those of you having problems with reception since June 12th, are these now VHF hi stations?

My CM-7000s, I have two, are almost unable to receive the 2 stations here that switched back to VHF hi. They break up or will sometimes read "no signal." This is the CM-7000's problem. On my other CECBs, the 2 hi VHF stations are the strongest stations I get. Only the CM-7000s have this failure. Since the CM-7000 has the best reception, by far, on UHF, this is really disappointing.

Oh, and I also have the problem mentioned above with intermittent blurry PQ, on my Ion station. With these two newly found problems, I drop the CM-7000 to a not recommended.
post #1239 of 1483
Quote:
Originally Posted by JNinCA View Post

For those of you having problems with reception since June 12th, are these now VHF hi stations?

My CM-7000s, I have two, are almost unable to receive the 2 stations here that switched back to VHF hi. They break up or will sometimes read "no signal." This is the CM-7000's problem. On my other CECBs, the 2 hi VHF stations are the strongest stations I get. Only the CM-7000s have this failure. Since the CM-7000 has the best reception, by far, on UHF, this is really disappointing.

Oh, and I also have the problem mentioned above with intermittent blurry PQ, on my Ion station. With these two newly found problems, I drop the CM-7000 to a not recommended.

Wanna try an Apex DT502?
post #1240 of 1483
Quote:
Originally Posted by JNinCA View Post


My CM-7000s, I have two, are almost unable to receive the 2 stations here that switched back to VHF hi. They break up or will sometimes read "no signal." This is the CM-7000's problem. On my other CECBs, the 2 hi VHF stations are the strongest stations I get.

did you test both boxes with the very same antenna, placed on the very same spot? i'm just trying to double-check this fact before blaming the CM-7000. lots of people all over the country are having problems with the Hi-VHF stations.

it's possible that this converter worsens the problem a bit, though.
post #1241 of 1483
My CM does as well with VHF as the Zenith and Zat. Three stations moved to hi-VHF June 12, and another station had been lo-VHF last year, no problems. With the Big 5, I get maybe one glitch a night since June 12, but I get the same thing from the UHF stations that didn't even move! The CM has the most trouble with a couple second tier UHF stations. One shows a broadly fluctuating signal, the other shows 100% signal. I think both are fluctuating, one's just too rapid to register. It cuts out about once a minute, while the Zat and Zenith manage to lock the signal.
post #1242 of 1483
Offering Zenith-901 or one coupon in exchange for CM-7000.



pm or email pl.
post #1243 of 1483
After testing between the Zenith-DTT900 & 901, Samsung LNA37550, & the CM7000, I find the CM7000 is most disappointing with VHF-HI. It hiccups quite a bit with all but the closest VHF stations. I do see a rare hiccup on the other 2 units, but it is annoying enough on the CM7000 to make those channels un-watchable. This happens even on one of the channels that displays a solid 100% on the strength meter????? (40 miles-28.8kw) The multipath is severe at my location, so I think it is the likely culprit.
post #1244 of 1483
Sounds like lightning to me. Lightning and VHF don't mix.
post #1245 of 1483
Quote:
Originally Posted by luminance View Post

Sounds like lightning to me. Lightning and VHF don't mix.

Agreed!!

I did try them during a thunderstorm, and the CM was progressively worse than the others. The hiccups still exist on the CM7000 even when there are no storms within a 100 mile radius.
post #1246 of 1483
Yes it's been noted many times that while the CM may be slightly better for weak signal, if you have any multipath (which you're more apt to get on upper VHF channels) the Zenith is the way to go. I've got both and I can say for a fact that's what I've found.
post #1247 of 1483
VHF antenna beamwidth (60 - 70 deg) is typically much larger than UHF antenna beamwidth (20 - 30 deg); as such VHF channels are more susceptible to multipath interference from a different direction.

After 06/12, I have received all VHF Hi channels from LA (7, 9, 11, 13) 90 miles away perfectly (with a good outdoor antenna + pre-amp). My house is on the hill top with no building in the path so there is no multipath. I also never notice the 4.2 WX+NR picture problem. My guess is somehow it is related to multipath also; the AGC loop may lock to the weak signal path in a certain condition and 480i signals are particular tuned to this. The AGC loop is designed to be very sensitive (to weak signals) but then it becomes unstable in muti-signal interference condition.
post #1248 of 1483
Quote:


My primary issue is that......I was receiving WLIW-21 the day prior to the transition (and for over a year prior to that).
Why should I need to move or upgrade my antenna?

Though it is remotely to be the reason, WLIW is on real 22 before 06/12 and is now on real 21; if you use an indoor antenna, the sweet spot may be different even though they are adjacent channels (i.e. there are many reflections in an indoor environment).
post #1249 of 1483
I lost the UHF16,28,45 channels locally (even after resetting and rescanning) but the newly transitioned VHF10, 13 were fine. I believe the tuner actually failed, because my other boxes worked perfectly on those UHF stations when swapped in. I had to RMA it to Solid Signal. I was pleased with its reception, hope my new one is as good and stays good.
post #1250 of 1483
i had to move my monoprice antenna from the wall by my window to on top of my chair to get 11, 13, 7 which made 2 and now 9 weak. One of these days i'll start moving it around the room again to find a new sweet spot so it will be off my chair.
post #1251 of 1483
Quote:
Originally Posted by dagger666 View Post

One of these days i'll start moving it around the room again to find a new sweet spot so it will be off my chair.

That would be outside, at least 10' above the roofline.
post #1252 of 1483
I got my new one very promptly from Solid Signal. UHF is back. But..it did an odd power off to red light, power on, off to red a few times, stopped, and has been fine for many hours. My fingers are crossed..It acted like I just plugged it in, but power plug was secure.
post #1253 of 1483
My CM-7000 is failing the Flash Test in the diagnostic menu. The box seems to be functioning well in all respects otherwise. I'm wondering if anyone else who've received their CM-7000 recently is also having a Fail on the Flash Test.
post #1254 of 1483
Quote:
Originally Posted by snuffymcduffy View Post

My CM-7000 is failing the Flash Test in the diagnostic menu. The box seems to be functioning well in all respects otherwise. I'm wondering if anyone else who've received their CM-7000 recently is also having a Fail on the Flash Test.

Thanks for the diagnostic menu headsup...

Am doing said diagnostics on unit 1 of 3 as I type this...is this process really long & tedious? The audiobeep is taking like forever...
post #1255 of 1483
The Audiobeep Test doesn't end on it's own - you can stop it by pressing the OK button. Whether you can hear it is the actual test - so it requires you to give it a pass. I don't know which button you'd need to press to fail it and see it turn red.
post #1256 of 1483
Quote:
Originally Posted by snuffymcduffy View Post

The Audiobeep Test doesn't end on it's own - you can stop it by pressing the OK button. Whether you can hear it is the actual test - so it requires you to give it a pass. I don't know which button you'd need to press to fail it and see it turn red.

Thanks, snuff. I redid the test and my unit gets the notorious "red" grade on the flash test...even with several reboots. No apparent problems though...but wonder if there are any available fixes to a failed flash test.
post #1257 of 1483
Beep Test doesn't seem to do anything. Flash, Ram and Tuner Pass. Video test goes to a 4 section black & white pattern until OK is pressed again, then shows Pass.

'Menu' exits, then any button reboots.

What am I missing?
post #1258 of 1483
With the audiobeep test I hear a repeating beep from the TV speaker. What build date does your box have in the setup section of the regular menu? Did you buy yours recently?
post #1259 of 1483
Quote:
Originally Posted by confuzzled View Post

Beep Test doesn't seem to do anything.

If it helps, mine doesn't either out of the RCA audio output jacks.
Perhaps it is only on the RF modulator Ch-3/4 out?
post #1260 of 1483
Quote:
Originally Posted by WeThePeople View Post

If it helps, mine doesn't either out of the RCA audio output jacks.
Perhaps it is only on the RF modulator Ch-3/4 out?

Mine definitely work via the RCA jacks. But note that the level is fairly low compared to normal audio.

It would have been nice if they had alternated between left and right channels (with some sort of indication which was which on the screen.) Would help confirm that the unit was hooked up properly.

I had one of the tests fail on one of my boxes a while back. Can't remember which one - maybe the flash test. But I retested it a second time and it worked fine. Maybe a SECDED thing?
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