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Old 10-01-2012, 05:30 PM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
Posts: 8,821
Now that I've experienced the heat put out by the 3-section filament dropping resistor, I've been thinking how it could be eliminated.

I crunched the numbers and came up with about 97 volts consumed by the tubes including a 6.3 VAC replacement picture tube. If I assume 125 VAC at the plug, a 20uF AC capacitor would do the trick.

However, those two taps are there for light bulbs that illuminate the VHF and optional UHF channel knobs. I did a little research and found there are 130 VAC white LEDs available in a BA9S base.
They're a bit harsh compared to the yellowy incandescent blub, but work fine.

I figure I'll give it a try and if I don't like the results it's easily reversible.

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