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RCA VICTOR "Nipper IV"
10/23/2000 10:48:52 PMFrank
I have an RCA NipperIV radio which I am attempting to repair. I can't find any info on this model. I need a schematic and some advice with the tubes.
When I turn it on, nothing happens, no glowing tubes, no humming, nothing!
Please help!
11/1/2000 6:31:50 PMJohn McPherson
Hi,
Is this radio Ivory on the front with red knobs?

If so, it was produced in 1939. Model would be 9-SX-* The last digit only defined color scheme. Chassis' were the same.

http://www.NostalgiaAir.org/NostalgiaAir/Riders/showinfo.asp?PATH=RCA&IMG=_RCA_10-38.gif&INF=9SX4
http://ww3.nostalgiaair.org/schematics/RCA/_RCA_10-39.gif

The radio uses a series filament string, and probably one of the tubes has an open heater.

When you find the bad tube, you are partway done if it is any fix. The only other thing to do is to replace the power supply filter cap. More often than not, it has gone bad with time.

When those two items have beencovered, if it still fails to work properly, check for a weak tube, and if all is well, then check the coupling caps. They often go bad too, but not quite as often as filter caps.


: I have an RCA NipperIV radio which I am attempting to repair. I can't find any info on this model. I need a schematic and some advice with the tubes.
: When I turn it on, nothing happens, no glowing tubes, no humming, nothing!
: Please help!



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