Recently I came in the possession of an old TS 830. It was (badly) modified for use om 27 Mc. The receiver was not functioning and the PA produced almost no output.
Also the display did not show the correct frequency at irregular moments.
A real challenge....
The TS 830 with the rf board removed.
The front-end circuits were short circuited.
Also some wrong replacement type of FET was used.
The rf board under test.
A new FET as replacement.
Temporarily on the "wrong" side to facilitate measurements.
Measurements showed that tuning of teh first stage was almost impossible. Also a lot of rf was "lost"somewhere.
It was found out that the input transformer was defective.
After replacement measurements now showed no rf on the drain of the FET.
ONce again a faulty transformer.
Both the input and output transformer of the first receiver stage were having a short circuit between the primary and secundairy winding.
The input transformer has been replaced.
The output transformer still has to be delivered.
So....so far so good, but still to be continued.