08-07-2019, 10:18 AM
What are you using for a VOM to make both voltage and resistance measurements?
Some digital meters DVM's can tell lies when measuring the resistance of an inductor and capacitance of a "leaky" capacitor.
Use an analog VOM to make B+ measurements as compared to published values for the radio.
Some models of Philco radios have RF, oscillator coil problems. In between layers of windings a celluloid insulating liner was used. The celluloid decomposes and etches into the copper via cracks in the enamel. The oxides and cause leakage winding to winding.
Poor mechanical connections to the chassis can also be a problem. No ohmmeter can detect the issue, so advice is to solder to chassis or drill out rivet and replace with new hardware.
Why were there wrong connections? Was this a radio hacked by another?
I see this radio has been an on-going project.
Take some very sharp pictures of the under chassis, often there is a clue to what is going on that a picture would help.
Oscillator failure can be diagnosed by using a portable radio and searching for the oscillators signal. Re-tuning the the test radio up and down the band to verify the oscillator does not "drop out".
Chas
Some digital meters DVM's can tell lies when measuring the resistance of an inductor and capacitance of a "leaky" capacitor.
Use an analog VOM to make B+ measurements as compared to published values for the radio.
Some models of Philco radios have RF, oscillator coil problems. In between layers of windings a celluloid insulating liner was used. The celluloid decomposes and etches into the copper via cracks in the enamel. The oxides and cause leakage winding to winding.
Poor mechanical connections to the chassis can also be a problem. No ohmmeter can detect the issue, so advice is to solder to chassis or drill out rivet and replace with new hardware.
Why were there wrong connections? Was this a radio hacked by another?
I see this radio has been an on-going project.
Take some very sharp pictures of the under chassis, often there is a clue to what is going on that a picture would help.
Oscillator failure can be diagnosed by using a portable radio and searching for the oscillators signal. Re-tuning the the test radio up and down the band to verify the oscillator does not "drop out".
Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
