Problem with 1 device and 1 frequency

[lost@c]

I have a strange problem where 1 of my capture cards (I have a dual and a single) has trouble with 1 frequency (only).  There are five in my region.  The issue is recordings and live tv are mostly blank with occasional block images in the upper part of the screen.  It looks like a reception problem but of the 5 frequencies, the ones above and below all seem to work fine.


To troubleshoot, I stripped out all my channels apart from 1 on each frequency.  I then watched each 1 for 20 second.  .  The failed one was  the 4th (Prime).  While I only have these 5 channels set up at the moment, the same issue occurs on all channels on that frequency (602.000)


If I use the copy setup to other devices function, then try again using the new card, I get proper results so I comfortable that the scan info is ok.


Fresh set of logs attached showing;

Stop Recording service
Start Recording service

Scan channels on card in question and select 1 on each of the 5 frequencies

Open next card and use copy function

Make card in question top of the list

Watch each channel in turn for 20 second  (4th no good)

Change next card to top priority

Stop Recording service
Start Recording service

Watch each channel in turn for 20 second (4th good)

Any thoughts appreciated

[sub]

It looks like reception/signal problems, which would tally up with your description.

2020-08-21 08:20:12.940 [DEBUG][14] About to tune BDA graph:
<tuning>
<type>DVB-T</type>
<locator>
<frequency>602000</frequency>
<bandwidth>8</bandwidth>
</locator>
<service_id>1404</service_id>
<tsid>33</tsid>
<onid>8746</onid>
<service_type>25</service_type>
<provider>Kordia</provider>
</tuning>

2020-08-21 08:20:12.940 [DEBUG][14] DigitalRecorderDVBT::Tune@1
2020-08-21 08:20:12.940 [DEBUG][14] DigitalRecorderDVBT::Tune@2
2020-08-21 08:20:12.940 [DEBUG][14] DigitalRecorderDVBT::Tune@3
2020-08-21 08:20:12.940 [DEBUG][14] DigitalRecorderDVBT::Tune@4
2020-08-21 08:20:12.954 [DEBUG][14] DigitalRecorderDVBT::Tune@5
2020-08-21 08:20:13.320 [DEBUG][14] DigitalRecorderDVBT::Tune@post
2020-08-21 08:20:13.348 [DEBUG][14] Calling LockChannel()
2020-08-21 08:20:14.365 [DEBUG][14] locked=1, present=1, strength=-9000, quality=3 (took 1014ms to check)

[lost@c]

Thanks Sub. That's where I got to too. My issue is that it's split right at the PC to both cards and its ok on the other frequencies and other card. I'll see if loosing the spliter helps as a first step.

[lost@c]

Interestingly, according to my TV reception meters which is fed from the same splitter, my signal strength is quite low across the board. I appreciate these sorts of meters are not always very accurate but it looks like a good place to start.

Thanks again Sub. I'll report back when sorted

[sub]

If you temporarily remove the splitter, does it help?

[lost@c]

Will try shortly. Working from home is getting in the way at the moment

[lost@c]

Well that was an interesting exercise! Capture cards aside, connecting directly to my TV (that has strength and quality meters) showed a strength of 78% (of what I hear you ask ). With a 2 way splitter it dropped to 58% and with a 4 way (what I was using) down to 48%. Its logical that the more splits the more attenuation per output and I guess this was just enough to tip it over the threshold and make it hard to lock. Not sure if it makes a difference but the higher frequency that was working before was SD while the 1 I was after was HD. Does HD need a stronger signal I wonder? With the 2 way, the problem channel now works but I have 3 things in total in the vicinity so will need to rethink my distribution.

I have another splitter (2 actually) in my ceiling space so might look to reduce the number up there and maybe even put a powered 1 instead of a passive as the first and closest to the antenna. This is what happens when you extend your house!

Thanks again. I'll called it sorted.