Compass light resistor?

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N170BP
Posts: 552
Joined: Mon Jul 22, 2002 7:24 pm

Compass light resistor?

Post by N170BP »

What is the purpose of the 750 OHM (I think) resistor mounted
in-line in the wiring going to the magnetic compass light?

I've discovered that the lead has broken off at the end of this
square-ish (about 1.25 inches long) resistor, and hence the
compass light wasn't working. If I temporarily provide 12 volts
(by-passing the resistor), the little red mag compass light works.
Is the resistor required? If so, where do I get a replacement?
Bela P. Havasreti
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'54 C-180
N2540V
Posts: 86
Joined: Tue Apr 23, 2002 11:57 am

Compass light resistor?

Post by N2540V »

A resister in line with the light increases the circuit resistance (R total = R1 + R2).
This lowers the voltage at the bulb and makes it dimmer.
Somebody thought it was too bright in the past.

An equivilent resister can be purchased at any electronic parts store. For example Radio Shack, Fry's, and several others.
If doing it new, one should watch the wattage to make sure the resister can take it.
Jim
N170BP
Posts: 552
Joined: Mon Jul 22, 2002 7:24 pm

Post by N170BP »

Thanks Jim.

I think I'll go sans resistor, as I'm happy with the brightness
of it as-is (without a resistor).

Thanks again for the reply.
Bela P. Havasreti
Image
'54 C-180
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