A radio like that often has tube filaments wired in series. Any one open and there won't be voltage on the others.
With an ohm meter check continuity of filaments on each tube between pin #1 and #7.
Filament voltage starts at the rectifier and will go through around 2K @ 10 watt wire wound resistor before going to tubes. This resistor could also be open?
Norm
:I have an old portable radio (Red) in a leather case from the late 1950-or early 1960 era.This radio is mfg in Japan with the name International on it. It is AC/DC, as many back then were. The tubes used are pretty much typical (I think) 3S4/1U5/1T4/1R5. I am not getting any filiment voltage. Anyone know where to obtain schematic/tube placement chart?? Radio measures approx 3 3/4 x 6 inches
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