Re: Another 19 set rebuild
Well, you have replaced the caps, which tend to fail catastrophically - or cause something else to fail similarly, because they go dead short.
Now you need to start on the resistors. Most of them will have changed value, and most will be out of tolerance now. That can often lead to a receiver that sort of works, but is low gain.....and other symptoms of poor performance.
Its a tedious job, and some resistors don't need to be changed even if they are out of spec. An example would be grid leak resistors, which might be 470k for instance. If they now read 600k (say), then I wouldn't bother to change them. On the other hand, resistors feeding anode, screen grid or cathode need to be in tolerance, because excess ohms here will mean loss of voltage at that particular valve connection, and potentially loss of gain, because resistors tend to go high in value, and reduce current levels.
Other than that, check the valves (on a valve tester if you have one), and re-align the set, which will not help a weak BFO, but it will give you an even performance across the whole frequency range.
Richard
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