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Old 04-13-2004, 10:36 PM
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wa2ise wa2ise is offline
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I guessed with 300 ohm resistors no luck. The seleniums are behind the CRT so It's hard to get a probe back there to measure.
I'd use resistors around 5 to 10 ohms. It's a little hard to calculate the desired ohmage when working with a half wave rectifier with filter caps circuit. Most of the time the rectifier diode is not conducting. It does conduct for a brief period of time at the top of the AC waveform, to top off the filter cap. That makes for a relatively large current spike. This spike is about 20 times larger than the B+ current draw by the rest of the set from its power supply. A rough guess for that current would be around 200ma. Twenty times that comes out to 4 amps. and to lose 20V would mean a 5 ohm power resistor. 300 ohms aint gonna curt it
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