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Resistor substitution question:
#1

I’m working on a couple of old Philcos, 37-84 and 71B.  Need to order some resistors.  Problem is, when checking some of the vintage parts suppliers, the resistors they stock are not within 10% of the values I need.  As an example, I need a 6k and 13k but the closest they list are 6.8k and 12k-15k.  I could probably order from one of the major parts suppliers but I would prefer to deal with our “vintage radio” guys.  I guess the bottom line is, can I safely assume 20% tolerance or stay within the 5 to 10% norm?  I’ll probably go with 1w if available.

Thanks!
Hokep61
#2

Original spec was 20% so your fine. Most of them are going to be 1/2w, the ones that like 3/8 in dia are 3w. Rule of thumb is that for the most part the higher wattage resistor are going to in the power supply circuit and in the cathode circuit of the output tubes. The two power resistors in the hv on the 84 are 2w. Size wise resistor have gotten alot smaller in size but can dissipate the heat well.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

Thanks Terry for the reply and info. Wasn't sure of the tolerance of the old resistors.

Hokep61




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