On 11 Sep 98 at 0:38, Tony Duell wrote:
The audio output circuit is quite simple. Sound comes
from pin 19 on the
6560 VIC chip (UB7). It's filtered by C17 (0.01uF), R16 (1M) and C20
(0.1uF) and fed to the base of Q5 (2N3904) which is connected as an
emitter follower. The collector is tied to the +5V rail. The emitter load
is R15 (470 Ohm). The emitter is also connected to the +ve side of C16
(1uF), the other side of which goes to pin 3 of the monitor socket.
Interesting. The schematic I have in the Programmers Reference Guide is
obviously for a different model. The schema is c-writ 1980 and labeled
"Schematic Main Logic Version E"