TV tubes

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145° Mesa St. Redding, California 96001

Entirely by accident I hit upon a very simple (if you have the tester) method of rejuvenating weak high tension (voltage) magneto output. I have a voltage continuity tester.

About 50 years ago a radio friend drew a diagram and suggested used radio parts for a condenser (now called capacitor) and continuity tester for automotive use. I have used it all these years and it is powerful enough to trace out a path of shorted contacts in the underside of a distributor cap!

It is not impossible to get the parts today but will take some scrounging as they have been outdated by solid state (transistor/diode stuff)- Here it is, with diagram.

I used one half of a 750 volt radio power transformer (that was the common type in use then), the reason being that a full 750 volts might melt out a condenser and half voltage will do the job fine-about 350 volts or so. Next comes a # 80 power tube (Radio Shack can supply the oldies). Next a 1 Micro-Farad Condenser which I am told is no longer available so use a good capacitor from a small electric motor-the run up to 200-300 MFD'S. Since you will need a ham radio friend on this he will explain all about these things-I don't know that much.

Next is a NEON 110 volt test light-they screw into a regular 110 volt socket. Use about a 50,000 ohm resistor with it. A base for your # 80 tube, 1 toggle switch, some phone jacks and test prods, another toggle switch for your neon light and that's it. I added a pilot light for fun but not essential.

If you get careless and touch the test prods it won't kill you, otherwise I'd have been dead long ago, but you won't make that mistake again for a long time.

My friends says they use this method to rejuvenate used TV tubes. It seems to clear out the 'junk'in the connections. I recently 'zapped' 2 Bosch AB 33 armatures. Both were dead-no continuity. One 'broke through' and established continuity but the other wouldn't come to life.

To use on any point operated system just open the points or put a piece of paper between them and touch the 2 halves of the points with the prods and watch the spark output on the high tension lead. Two or three times is enough.

Condensers last for years but many times it's nice to be able to test them out for short or leakage. They will accept one flash from your test prods and hold the charge for several seconds before accepting another one. The neon light will burn steady if the condenser is shorted-if good it will vary from one glow to a weak flicker. Each time you test it discharge it by touching the wire to the case. It is not necessary to remove the condenser from the unit to test it-jus remove the wire and let it dangle. Have fun!