[mythtv-users] Debugging hdhomerun - can I record the same show from multiple tuners in duplicate?

[Stephen Worthington]

On Sun, 26 Feb 2023 18:20:14 -0600, you wrote:

>Hi,
>
>  I have two HDHomeRun tuner boxes (a dual and another quattro) and I 
>suspect one of them is broken. I strongly feel it is the quatrro, but 
>for now, I am going to assume that anyone of them could be broken 
>because the only evidence I have is that some shows turn out to be 0B 
>recordings. I have already power cycled and tested with hdhomerun 
>control/config app on win10. They seem to work fine when watching live 
>TV in myth also. However one of the boxes very often produces 0 bytes 
>recording.  I would like to record the same show on of both my tuner 
>boxes at the same time to check if this is a transmission issue or tuner 
>issue. My antenna is brand new and I doubt it is at fault.
>
>   Both units are several years old, so it could be that their adapter 
>is broken. If so, my app on windows should create problem or attempting 
>to watch live TV should produce errors, but I do not get any of those. 
>So, I have not tried fixing adapters
>
>   Also, when I added my second HDhomerun unit (quattro) when I bought 
>it, strangely enough, I got 8 tuners instead of 4. So, I am not sure if 
>something is wrong with backend setup of this tuner.
>
>   I run standard debian 11.6 with default kernel adding mythtv 
>0.32-fixes using debian-multimedia repository. I have a gt1030 nvdia 
>card, but that is unlikely to be relevant as this is a recording issue.
>
>   Recording that produces 0B is coming on digital channel 18 
>(Dallas/KTXA-DT 21.1)
>
>Regards
>Ramesh

Recording rules do have an option to set the "Preferred Input".  If
you edit a recording rule, go to Schedule Options and change the
second selection box from "Use Any Available Input" to the input you
want it to use.  If the preferred input is not available due to using
it causing a scheduling clash, I believe the scheduler will then use a
different input, but I have never actually had that happen as I have
too many tuners to get many clashes.

It is difficult to create two normal recording rules to record the
same programme.  The only way I can think of is to use one of the API
interfaces, such as the Services API, to create the second rule.  If
you try from the GUI, you only get offered the option of editing the
current rule, and it may be that the Services API will reject creating
a second rule for the same showing.  The only way to find out would be
to try.

However, you can create two manual recording rules for the same time
period on the same channel.  Mythfrontend > Schedule Recordings >
Manual Schedule, then create two manual recording rules with the same
settings, but give them different titles.  On the second page of the
settings there, use the Schedule Options to set them to use different
inputs.

To see which tuner was used for any recording, in mythfrontend go to
the recording and press the I (Info) key twice.  Then scroll down if
necessary until you see the "Recording Input" field.  This is the
capturecard.displayname field from the database.  I have manually set
all of mine so that the different virtual tuners can be distinguished,
but the defaults should show which physical tuner was used.

In the mythbackend.log file you can find a report line for each
recording that is written at the end of the recording which will tell
you the recording's status and the virtual tuner number
(cardinput.cardid):

cd /var/log/mythtv
grep "overall_score=" mythbackend.log

A good recording should look like this:

Feb 27 16:04:00 mypvr mythbackend: mythbackend[1446471]: I TVRecEvent
tv_rec.cpp:856 (FinishedRecording) TVRec[11]:
FinishedRecording(1003_2023-02-27T01:58:00Z) good
recq:#012<RecordingQuality overall_score="1"
key="1003_2023-02-27T01:58:00Z" continuity_error_count="0"
packet_count="17913081" />

That is all one long line in the log - my email client wraps long
lines.  The virtual tuner number is the [11] after "TVRec".

And this is what I got for a bad recording recently:

Feb  1 22:34:00 mypvr mythbackend: mythbackend[105007]: I TVRecEvent
tv_rec.cpp:841 (FinishedRecording) TVRec[94]:
FinishedRecording(10070_2023-02-01T07:29:00Z) damaged
recq:#012<RecordingQuality overall_score="0.8"
key="10070_2023-02-01T07:29:00Z" continuity_error_count="45265"
packet_count="25817462" />

I think I had rain fade on my satellite dish that day.