06-03-2012, 05:50 PM
Managed to obtain a diag for the computer, what a mess. Each sound channel is fed to the final amp stage via a seperate op amp. There are four op amps in the same package so it is concievable that one of the amps could go down and remove that particular channel feed. Time to dig out an audio signal generator and go fishing.
The burrr part of the beep is apparently caused by stray signals on the data line that float around until the 555 timer initiates the data bus. Clever, but heavy usage of 74 series chips.
The burrr part of the beep is apparently caused by stray signals on the data line that float around until the 555 timer initiates the data bus. Clever, but heavy usage of 74 series chips.
