04-19-2022, 02:23 PM
The part that looks like a molded mica wired across the .25 uF cap is the 400 ohm wirewound resistor. Some low wattage wirewounds were made in that style in the 1930's. If the resistor measures near 400 ohms I would leave it alone. The original .05 uf was changed in later production to .25 uF to prevent oscillation of the IF amp as described in this service bulletin.
https://philcoradio.com/library/download...es%204.pdf
The bias resistor shown in the photo is called a "candohm". It actually is a wirewound resistor which uses the chassis as a heat sink. Again if it measures the correct resistance its best left alone.
#25 and 27 are mica caps which are part of tuned circuits and affect the calibration. They should not be replaced unless definitely known to be bad.
https://philcoradio.com/library/download...es%204.pdf
The bias resistor shown in the photo is called a "candohm". It actually is a wirewound resistor which uses the chassis as a heat sink. Again if it measures the correct resistance its best left alone.
#25 and 27 are mica caps which are part of tuned circuits and affect the calibration. They should not be replaced unless definitely known to be bad.
