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<p>On 09/05/2022 13:33, James Abernathy wrote:<br>
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<div dir="ltr" class="gmail_attr">On Mon, May 9, 2022 at 7:41
AM Paul Harrison <<a href="mailto:mythtv@mythqml.net"
moz-do-not-send="true" class="moz-txt-link-freetext">mythtv@mythqml.net</a>>
wrote:<br>
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<p>On 09/05/2022 11:41, James Abernathy wrote:<br>
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<div dir="ltr" class="gmail_attr">On Sun, May 8,
2022 at 8:39 AM James Abernathy <<a
href="mailto:jfabernathy@gmail.com"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">jfabernathy@gmail.com</a>>
wrote:<br>
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<div>Results of my first test of the Hauppauge
WinTV Quad HD in a new system with Ubuntu
20.04.3 LTS and mythtv v31.</div>
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<div>I installed Ubuntu 20.04.3 minimal and
added the apt repository for v31. The
install was as expected and I setup the 4
tuners to correspond to the Quad tuner PCIe
card.</div>
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<div>I used a table top antenna in my lab
since I didn't have a tap for the big attic
antenna. I could not get the PBS station 40
miles away as expected but the nearby
stations all scanned. While watching
LiveTV, I noticed that the signal strength
displayed was 80-100% instead of 40-50% in
V32 Ubuntu 22.04, my production backend. </div>
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<div>I'll try later today or tomorrow to move
the test PC to a room that can access the
same 8-way splitter that all my other tuners
and tvs are connected to. At this point
it's looking like the difference between v31
and v32 or Ubuntu 20.04 and 22.04.</div>
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<div>Where I'm located with respect to the TV
towers you can get great signals with a coat
hanger jammed into the F-connector. </div>
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<div>Jim A</div>
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<div>I've narrowed down when the signal reporting
gets changed. On my newly built test system with
MythTV v31 on Ubuntu 20.04.3 LTS my signals were
reported as ~100% on most of my channels using my
Hauppauge WinTV quadTV as it had for years on my
production backend.</div>
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<div>I added the ppa:mythbuntu/32 repository and
upgraded to v32. The system updated all 21
packages and everything was working as before but
now on v32.</div>
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<div>But when I use Watch Live TV all my reported
signal strengths were between 40-50%. So the
change is MythTV v32 related and not the version
of Ubuntu. The OS remained at Ubuntu 20.04 with
latest patches without any package updates to
Linux during this test.</div>
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<div>Jim A</div>
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<p>Could be this commit which changed the signal strength
range for DVBv5 :- <br>
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<p><a
href="https://github.com/MythTV/mythtv/commit/5d76841b8c1878"
target="_blank" moz-do-not-send="true"
class="moz-txt-link-freetext">https://github.com/MythTV/mythtv/commit/5d76841b8c1878</a></p>
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<p>You could try starting the backend with --dvbv3 to see
what you get with the old DVB v3 API.</p>
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<p>Like other have said if it not causing you any problems
then I wouldn't worry to much about it. <br>
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<p>Paul H.</p>
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<div>You are correct. Starting the mythtv-backend with --dvbv3
does restore the signal strength to what I was seeing on
v31. </div>
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<div>So what I'm hearing is by default in v32 the signal
strength is based on dbm instead of %. Are there any
problems using --dvbv3 instead of the default??</div>
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<div>Jim A</div>
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<p>The value is still calculated as a percent in the range 0 to 100%
it's just the range of values accepted from the driver has been
increased.</p>
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<p>It was -100dBm to -20dBm it is now -100dBm to 0dBm. Previously
any value between -20dBm and 0dBm was being rejected and I think
it would fall back to the DVB v3 legacy driver and use the value
from that which will be the same value you got by forcing the use
of DVBv3.</p>
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<p>I think because you are in a very strong signal area the signal
strength was probably outside the previous allowed range but is
now inside the new range. I tried to find any documentation
related to what the range should be but a quick Google didn't find
anything so no idea which value is correct \0/ I recall there is a
DVB tool called femon that you can use to monitor the signal
input which may be useful to compare the output. <br>
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<p><br>
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<p>Paul H.<br>
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