QAM record problem with logs -- HELP please (1 Viewer)

[mm1352000]

Re: Update

Hi again cewillis

*Thank you* for reporting back.

I've tried several things to try to solve this problem, with no completely successful result.

1) an inline cable amplifier. Absolutely the wrong direction -- destroyed all reception on the HTPC.
2) a high pass filter that blocks frequencies below 54 MHz. No noticeable help, but probably can't hurt.
3) a few attenuators, 3bd, 6db, 8db. The 3db seems to help some, at least sometimes. I have successfully made some recordings that used to routinely fail; eq, start an analog (or KVOAHD) recording , followed by a KOLDHD recoding. Sometimes, I don't see anything at all wrong with the KOLDHD recording, sometimes just a few distortions. No complete failures yet with these channels.
However, the same sequence but with KMSBHD still has significant distortion, and an occasional failure (TVserver crash).
A 6db attenuator did not improve anything, and 8bd made it worse - although individual recordings (and viewings) still work.

Hmmm. I think short of getting a professional installer or the chip designer in you've tried all the right things there.

As mentioned before, the recently changed frequencies of KOLDHD and KMSBHD (103.25Mhz) are in the FM broadcast range of 88-108Mhz. I don't know what the really means, but resumably, there's no FM on the cable(?), and I can't put a Faraday cage around the HTPC.

I don't think FM radio is provided intentionally in the cable so unless it leaks in via interference that would be a non-issue. I had a bit of a chuckle at the Faraday cage comment D) but in all seriousness I'm sorry that you haven't been able to find a solution.

And it appears the only way 'around it' is the avoid the situation.

...or buy another tuner if you can afford it and have the connections/space for it. Far from ideal I know...

mm

 

[cewillis]

good news? (or contraditory anyway)

I finally got around to installing Hauppauge's WinTV software. This also included updating the HVR-2250 driver.

I used this abbreviated test sequence with MP and WinTV:
Start a recording on analog channel 3
Start a second recording on clear QAM channel KOLDHD (one of the problem channels).

Results:
MP: second recording is somewhat pixelated and distorted.
WinTV: very similar. (as if the problem is the tuner)
(results with the other problem channels are worse)

Second test sequence:
Start a recording on clear QAM channel KVOAHD.
Start a second recording on clear QAM channel KOLDHD.

Results:
MP: second recording is 'somewhat' pixelated and distorted.
{{WinTV: NO PROBLEMS! Second recording is FINE! (as if the problem is different tuner setups, and not the tuner per se??)
(again, the MP results with the other problem channels are worse -- but WinTV does not have any problem)}}
Overstatement -- if I watch long enough, the WinTV recording has similar problems. Don't seem to be as much.

{{Any realistic conclusions from this?}}
Looks like it's all tuner or driver, as suspected before.

Notes:
Viewing all of the above .ts recordings is by using windows media player, as the WinTV has some unimportant 'renderer' problem.
I have contacted Hauppauge about this --- we'll see what happens.

 

[cewillis]

Final Update:

I had a couple of months of email discussions with Hauppauge. They have sent me 2 different 2250s, including the 'new improved' version. Neither work any better than the original -- eg, they do not correctly tune the channels at 103.25 MHz on the 2nd tuner when the first tuner is already in use. Again, these channels are in the FM radio band.
Hauppauge professes to be puzzled, and it still investigating (theoretically).

HOWEVER!! my cable company finally changed the frequency of these channels to 'move them out of the FM band'. And no more problems! Both tuners work fine at the same time on all channels (except one, but that's a different story)
I asked the head technician to do this months ago -- the answer was 'No'. But now it's done.

Thanks again, mm, for your help and patience.