1930s resistor codes - Printable Version

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1930s resistor codes - bridkarl - 04-08-2026

I've run into these three resistors I can't figure out. None of them seem to match any charts I've looked at so far.

       
470k ohm???
   

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RE: 1930s resistor codes - glyphmon - 04-08-2026

While I'm pretty new, I think the chart I found on this forum suggests:
number 1 (yellow base, violet tip, orange stripe) should equate to 47K ohms
number 2 (yellow base, violet tip, yellow stripe - or no stripe = body color) should be, as you said, 470K ohms

As for number 3 I'm not sure how that one should be read.

What model is this?  Did you find what it should be according to the schematic?

Best wishes,
Roy

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RE: 1930s resistor codes - RodB - 04-08-2026

If it's a resistor it might be 100k. The center stripe is black.

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RE: 1930s resistor codes - bridkarl - 04-08-2026

I think that's right. This is a Fairbanks-Morse 5A which I just found the schematic on. I was actually doing ok without it until I ran into some caps with totally faded markings. Really simple design, easy to work on.Someone had replaced one of the 8mfd caps on the field coil with a 16mfd cap. ugh...

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