06-14-2016, 12:29 PM
Sorry OM meant 1LB4 the audio output tube. Pin 1 is the start of the filament string and should be at about +9vdc from B-.See post #8 for the filament wiring.http://philcoradio.com/phorum/showthread.php?tid=14647
>touched pins but could only get .042 v and a lighting bolt shows on my meter.
Not sure what pins you were touching so can't tell you what you should see. Only worry if the lighting bolt come out of your meter!
Would clean the toob sockets with a small tool, I used a small dremel cutting bit manipulating it by hand. This may fix the intermittent at the 1LE3.
With the set plugged in to an isolation transformer use a signal generator to inject a 455kc modulated signal the pin 2 of the 1LE3 at the rear of the chassis (mixer toob). If all is well should hear the signal in the spkr. At this point you can peak up the trimmers on the three IF transformers. If you can't hear the generators signal try injecting the signal on pin 2 of the 1LD5 closest to the tuning cap (1st IF amp). If you still can't hear it go to pin 2 of the next 1LD5 (2nd IF amp).
Terry
>touched pins but could only get .042 v and a lighting bolt shows on my meter.
Not sure what pins you were touching so can't tell you what you should see. Only worry if the lighting bolt come out of your meter!
Would clean the toob sockets with a small tool, I used a small dremel cutting bit manipulating it by hand. This may fix the intermittent at the 1LE3.
With the set plugged in to an isolation transformer use a signal generator to inject a 455kc modulated signal the pin 2 of the 1LE3 at the rear of the chassis (mixer toob). If all is well should hear the signal in the spkr. At this point you can peak up the trimmers on the three IF transformers. If you can't hear the generators signal try injecting the signal on pin 2 of the 1LD5 closest to the tuning cap (1st IF amp). If you still can't hear it go to pin 2 of the next 1LD5 (2nd IF amp).
Terry
