Jeff thanks for the info... DanDan, I have never seen a service manual for any Grey amp.
There is a thread here somewhere that talks about one but they were like most CB amps back in the day.
I will look for the thread
73
Jeff
Yep. The toroid power transformer is woefully undersize. The DC voltage on standby is over 20 Volts. Drops to around 12 under load. The high standby voltage tends to cause RF transistors to fail, frequently as you unkey. We learned to insert a 30-Amp "Bosch"-type automotive relay between the DC power and the amplifier board. Added a transistor to carry the load of the added relay's coil, and drove the transistor from the original relay circuit. This will remove DC power from the RF transistors in receive mode.Nomad I am sure is familiar with these
Thank you for the info... DanYep. The toroid power transformer is woefully undersize. The DC voltage on standby is over 20 Volts. Drops to around 12 under load. The high standby voltage tends to cause RF transistors to fail, frequently as you unkey. We learned to insert a 30-Amp "Bosch"-type automotive relay between the DC power and the amplifier board. Added a transistor to carry the load of the added relay's coil, and drove the transistor from the original relay circuit. This will remove DC power from the RF transistors in receive mode.
It's a bit like a small mammal. High metabolic rate, short life.
73
Thank you Brandon... DanNot sure if you already have this, but the schematic was on CBTricks