[martin.m]

It would be a good idea to read up on how valves work and the sort of voltages they need on their electrodes. It can be difficult to find the cause of a fault if you don't have a basic understanding of how something works. A circuit diagram would be a great help as well. Failing that, valve data, either a book or from the Internet, will tell you what each valve's pin connections are. With practice you will be able to fault find logically. As others have said, start from the power supply and work back through the audio stages, then to the IF and RF circuits.

Old capacitors are certainly a problem in vintage equipment but many faults are caused by resistors changing value or going open circuit. Good luck with your new hobby and please follow the advice on safety given by other members.

Regards
Martin