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Poor poor little National HRO Senior L76
#70

I finally got the digital readout to work properly on this beast. I started out using rectified heater voltage to power it but it didn't like it much at all. Worked much better w/a 9v battery.Ended up building a 12vdc p/s inside the rack p/s to power it. As Mondial said it is pretty sensitive so I had to attenuator the oscillator signal. Wasn't quite sure what is grounded on the counter but signal - power - and the mounting hardware had no interconnection. Grounding the power - to the chassis helped a lot and bypassing the 12vdc w/a .1 cap got it to settle down nicely. Works great now from 500kc-30mc. Haven't tried any of the low frequency coils yet.
I'm pleasantly surprised at how stable this old guy is after in little warm up time and the counter proves it.


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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


Messages In This Thread
OT RCA 6T71 1950 TV - by Radioroslyn - 06-13-2015, 10:19 PM
RE: Poor poor little National HRO Senior L76 - by Radioroslyn - 01-31-2017, 03:20 AM



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