right away when you plug in a radio and only get the meter lights and channel display that says that the MB3756 voltage reg is bad.
you said that the heatsink connected to this device was getting hot which also points to it.
however you are showing 8 volts on pin 9 of the PLL so that would say that the voltage reg is doing its job.
pin 10 of the PLL in this chassis should be grounded, and if it's not, it's because someone wanted to do a channel mod to it, so re-solder it where it went.
you have no voltage on pin 6 of the PLL which is your lock detector pin and it should be sitting at 8 volts. most likely this is because pin 10 is disconnected.
once you have pin 10 reconnected, check the voltage on pin 6, and you should get 8 volts.
if not, first thing to do is try to align the VCO coil per the service manual found here:
http://www.cbtricks.com/radios/teaberry/stalker_xv/index.htm
if you still don't get RX/TX after all this as indicated by the LED, you can try lifting one end of D25.
if this restores operation, then the problem is in the lock detector circuit itself, if not, you have other PLL/VCO problems.
LC
