800XL No Audio

[hueyjones70]

I have an 800XL that has no audio except for key clicks. I may have caused the problem because I did the SuperVideo 2.1 upgrade. After I finished the upgrade and tested it, I first thought it wasn't booting properly because I wasn't hearing the sound that usually occurs when it boots. I saw the ready prompt but I thought something was wrong in the boot process. After more troubleshooting, I determined that the boot was OK and I just didn't have audio. I tried a different POKEY and that wasn't the problem. Which components provide audio?

[TGB1718]

Pin 37 from Pokey to this circuit (SOUND input).

 

The keyboard click comes from GTIA pin 15 and is the BELL input to the audio circuit.

 

Edited April 13 by TGB1718

[hueyjones70]

I hope someone can explain this to me. When I connected the keyboard the audio returned. I disconnected the keyboard and the audio stayed.

Edited April 17 by hueyjones70
Misspelling

[_The Doctor__]

Intermittent connection in the area, PCB flexed during insertion, stayed connected when pulled.

[hueyjones70]

OK I need to try flexing the PCB.

Edited April 17 by hueyjones70
Misspelling

[_The Doctor__]

NOOOOOOO.  You should not purposely flex PCB, you can break connections, traces, and loosen failing or unseen things, possibly upset a weak swipe even (as seen on 1200XLs)

best to take readings while working, write them down. If it fails again, you can compare readings and find what changed.

Edited April 17 by _The Doctor__