This radio came in from an end user; something we don't normally do. The complaint was that after transmitting the radio would stop working for a time.
I felt that the 8V regulated rail was failing...or being dragged down...or being caused to shut down. Looking at the circuit I saw a 10uV electrolytic capacitor in the synthesiser circuit, after the 8V regulator. Removing the capacitor & testing it, I found the capacitor to be faulty on our ESR meter, so it was replaced. I also replaced the 1000uF supply capacitor as I didn't like the look of it, and the 8V regulator. It was an LM78M08 fitted & I replaced it with a LM7808 which is 1A rated as against the original that was 500mA rated. The radio was retuned & tested & unlike most new CB radioa had no difficulty producing a full 4W.
A quick on the air test to my radio amateur friend Stewart, 8.8 miles the other side of town & the job was done.
Recorded 26th April 2021
Richard G0OJF
