pjbroad wrote: ↑
Thu Dec 20, 2018 11:58 pm
I'm viewing on my desktop connected to the wired network. Both the pi0w and the p3 connect over the same wifi to the same desktop running kodi, but the p3 picture is fine, the pi0w is choppy. I've tried another pi0z and its the same choppy picture.
I wonder if TV RF signal strength is a factor? I get a perfect picture on all but a couple of channels on the p3, but no good channels on the pi0w. I did also noticed that if I reconnect my TV to the antenna (no splitting in any of my set-ups), I get a few additional channels and all channels are good quality.
Quick test on a Pi0WH and I get some odd results. It doesn't help that I've been having fun and games with my Draytek access points for a while where they won't route between two devices on the same AP(*).
Most of the channels I tried are fine, but Channel4+1 (COM7 ARQC, 746MHz for me) breaks up quite badly in the typical "bad signal strength" manner that DVB-T does. On Sandy Heath COM7 and COM8 are at only 49.6kW transmitted power instead of the 170kW , so it may just be the lower signal strength - I haven't checked the signal strength and error rates reported in TVH.
I have had a chat with the hardware designer for the TV-HAT. Pure speculation - no real evidence to back this up, and both devices have passed EMC tests. The wireless module of the Pi0W isn't in a can as on the 3B+, so I guess there may be different EMC patterns that could interfere with the TV-HAT, give lower S/N ratios and break up. We need to quantify it, which will really have to wait until the New Year.
One test I will try is switching the 0W to wired ethernet and see if that improves matters. And further does the Wifi chip "idling" cause issues vs totally disabling it. If anyone else seeing odd things can try either of those steps then they would be useful data points. I think "raspi-gpio set 41 dl" is going to be the magic rune to disable the Wifi chip totally, although adding "raspi-gpio set 45 dl" to disable BT as well would be sensible. (It may be "dh" at the end - need to check the default state when I have one in front of me again)
(*) Seems to be related to having VLAN IDs defined for the multiple SSIDs, remove the VLAN ID and it generally works. Must report it formally to Draytek.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
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