I am puzzled by a dead audio output stage using a uPC1242H ! DC checks shows 12 Volts on Pin 8 (supply) but Pin 6 (audio OUT) shows 0 Volts (should be ~ 6 Volt ie 1/2 Supply), Pin 1 (audio IN) is 0 Volts with ~ 1 V pp Audio Pins 4/5 are at Grounded . Resistance Checks, Out of Circuit on New IC's and compared to original are identical. Re-installation of new ICs show exactly the same response 0 Volts on pin 6 ! There is not a hint of a signal on pin 6, should show something even into a Dead Short.
What am I missing ? Pins 2,3,7 are all around 1~2 Volts.
Do I have Three Dead Chips !, I haven't seen that many failures at one time in years ?
I always check for a bad Audio Output Chip by measuring the Audio Out Pin and expect it run at about 1/2 Supply Voltage.
A circuit diagram would be nice, but I think the problem in "on chip" so a diagram is really not that helpful.
I guess I am just having a bad day !!
Yukio TIA.