05-30-2019, 03:41 PM
Ha, Ha, he 
Its good to have a sense of humor. Complex methods of testing require a LOT of patience and understanding.
I am a bit lost in the last few responses, The B+ is now O.K?
If so, testing and correcting for motor-boating can be easy, (take a guess and try something) or get "scientific" again
Here is a "list" of things in increasing obscurity.
The wiring has been re-routed plate and grid circuits are adjacent. Wrong value component installed or left out. Another short.. Shield missing usually the IF tube, flaky tube, try replacing all. Critical alignment adjustment or re-alignment because RF wiring disturbed or a critical component (usually a mica cap) has been replaced. An OLD mica cap in the RF/IF/OSC has drifted off.
The rectifier may be shot if the B+ is still low...
Go from there... I'll jump back in when your about to chuck the radio out the window...
+1 on the VTVM, I have used one or another for many many years. Only occasionally using the DVM just because I could not wait for the VTVM to warm-up and settle.
I used to leave the VTVM on 24/7 but after 6 mo the tube(s) get out of balance and has to be re-calibrated... Then the battery goes flat.
GL
Chas
Its good to have a sense of humor. Complex methods of testing require a LOT of patience and understanding.
I am a bit lost in the last few responses, The B+ is now O.K?
If so, testing and correcting for motor-boating can be easy, (take a guess and try something) or get "scientific" again
Here is a "list" of things in increasing obscurity.
The wiring has been re-routed plate and grid circuits are adjacent. Wrong value component installed or left out. Another short.. Shield missing usually the IF tube, flaky tube, try replacing all. Critical alignment adjustment or re-alignment because RF wiring disturbed or a critical component (usually a mica cap) has been replaced. An OLD mica cap in the RF/IF/OSC has drifted off.
The rectifier may be shot if the B+ is still low...
Go from there... I'll jump back in when your about to chuck the radio out the window...
+1 on the VTVM, I have used one or another for many many years. Only occasionally using the DVM just because I could not wait for the VTVM to warm-up and settle.
I used to leave the VTVM on 24/7 but after 6 mo the tube(s) get out of balance and has to be re-calibrated... Then the battery goes flat.
GL
Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
