PWM whine near earpiece in low signal phone call and loud sound sent to the other end
#27
(07-28-2021, 10:27 AM)dsimic Wrote: A few days ago, one community member complained on the #pinephone IRC channel about having some kind of weird interference on his PinePhone, during a 2G voice call. After some debugging, which included changing the audio-related modem settings through some of the above-listed AT commands (with no success), we came to a conclusion that we need a weird approach: let's make the modem antenna larger. Smile

With that mod in place, signal strength (as reported by the "AT+CSQ" command) went up from around -100 dBm, which is considered poor, to around -70 dBm, which is considered very good, and no interference was present during a voice call. Thus, I'd suggest that you try something similar, just to verify whether the issues are caused by the network and low signal strength. Of course, improving the modem antenna is nowhere nearly as easy as sticking a randomly shaped piece of aluminum foil to the back cover, but that's all just for the purpose of testing.

The attached picture shows what the "early prototype" looked like. Smile

Not surprised that the AT commands didn't work since sound stuff on the modem end is way after the microphone. Though AT commands affecting the power systems in the modem might have an effect.

That antenna modification is clever. Makes sense that it helped. Modem is less likely to drop to 2G and crank up the transmit power in a burst fashion.

I am going to try that.

(07-29-2021, 05:24 AM)mouffa Wrote: I thought down there was the Wifi/BT antenna and the 3 antennae on the top were for the modem.

I've tried to look for diagrams of which antenna is which and have not found any. So I don't know. In fact, I don't even know if the whole thing at the bottom is one antenna or two (no information on whether the left most antenna piece is connected electrically to the others).



Anyhow. If the modification was on the right antenna, that is a nice simple work around. If it is the wrong antenna, while it is still a nice work around, the fact it works would imply that there is some interference going on between the different antennas which is a larger problem (adding metal to the wrong antenna
  Reply


Messages In This Thread
RE: PWM whine near earpiece in low signal phone call and loud sound sent to the other end - by vortex - 08-14-2021, 10:20 AM

Possibly Related Threads…
Thread Author Replies Views Last Post
  Phone will not turn on (but sometimes will) insidetrip101 10 4,381 08-18-2023, 04:28 AM
Last Post: spha
  Pine phone main board part Generaltuxenburg 1 918 07-31-2023, 07:50 PM
Last Post: tllim
  No calls on Pine Phone Beta convergence edition polypode 1 1,108 03-06-2023, 08:04 PM
Last Post: rocket2nfinity
  Pine phone USB keyboard connection CleanEnergyCleanEnvironment 1 1,052 02-20-2023, 12:14 AM
Last Post: Kevin Kofler
  I cannot call or receive calls aka0kuro 6 2,902 01-13-2023, 05:31 PM
Last Post: alaraajavamma
Thumbs Down Phone is unresponsive theneedful 14 7,207 08-12-2022, 08:18 AM
Last Post: theneedful
  Phone Dead Already? MarsColonist 4 2,551 08-11-2022, 11:52 AM
Last Post: auanta
  PPKB with phone; phone dies while charging SwordfishII 1 1,294 06-08-2022, 04:14 AM
Last Post: SwordfishII
  Lost internal earpiece Veraendert 3 2,248 02-14-2022, 07:51 AM
Last Post: Veraendert
Shocked Pine phone caught on fire after inserting SDcard majikbear 6 3,476 12-01-2021, 01:34 AM
Last Post: ryo

Forum Jump:


Users browsing this thread: 1 Guest(s)