soviet resistor identification help and maybe lamps?

wrcooke at wrcooke at
Sun Mar 8 16:47:15 CDT 2020

> On March 8, 2020 at 3:20 AM Adrian Stoness via cctech <cctech at> wrote:
> not seeing anything els other then the 620hard to get any decent shots of them with out a macro lens though
> as for the lamps if i wanted to test them one at a time would i just givethem 12V directly? or would it be lower dont have a variable power supplyatm just an old pc one
> On Sun, Mar 8, 2020 at 1:44 AM Holm Tiffe <holm at> wrote:
> > Adrian Stoness via cctalk wrote:> > trying to identify these soviet resistors anyone familiar with how theymarked them i see 620 on these ones for the panel 

I found this document from the CIA in the 50s about Soviet parts:

Doesn't say much, but indicates they used either the numeric value printed on the resistor or the same color code we use.
If the lamps are incandescent you should be able to measure the resistance of the filament, which would likely be in the 100 ish ohm range.  A neon bulb should measure open (infinite) I believe.
If the lamps are incandescent, the R could be to lower the voltage/brightness.  You could try that resistor already there plus various values of resistance in series with the lamp to see if lights and how bright.  Or a pot.  With a 12V supply and a 1K R in series you couldn't push more than 12mA through it.  I would suspect that would be plenty safe.


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