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City: Manassas
State, Province, Country: VA
I have a 1940 ford car radio I'm trying to repair I am a stand still.
Vibrator works tubes light up have voltages to tubes still nothing.
Help
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City: Wellborn Florida
Check that speaker is working, output transformer is good. Did you replace all the paper caps and out of spec resistors?
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City: portland, OR
here's a schematic for the L-1760.
http://www.nostalgiaair.org/PagesByModel...014047.pdf
i have a schematic for the F-1740. they are similar but with different part numbers. and the L-1760 has two 7C5 audio amp tubes.
https://www.radiomuseum.org/r/philco_f1740.html#top isn't much help.
the outer winding on the lone oscillator transformer of older transitones frequently corrodes and is open. you might check the main osc coil [part no. 59 on the L-1760 schematic] for continuity. the antenna and RF transformers, too. and, i suppose all the other osc coils.
touch the tip of a soldering iron to the grid of the 7C5 audio tube. plug the iron in but leave it off. you should hear a hum if the audio stage is good.
you need to see the word "dial" in the left window to use the tuner.