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Old March 3rd 18, 05:01 PM posted to rec.radio.amateur.boatanchors
Scott Dorsey Scott Dorsey is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 758
Default Heathkit SB-200 Help

Edward Vignati wrote:

Scott thank you , the transmitter is an Elecraft KX3 into a KXPA100, I'm not good with a scope, even though I have one, I will check the resistors, the band switch and grid bypass caps, Thank you very mych


Yeah, but watch the B+ when you key down also. If one or more diodes is
partially failed, you can get into a situation where the supply can deliver
a lot of current from the bypass electrolytic quickly, but after a few seconds
it sags because the electrolytic can't charge up as quickly as it discharges.

Big broadcast transmitters often have neon lamps across all of the diodes
in the series string so that when one goes open or high resistance the lamp
lights up.

If the power drops but the B+ holds more or less steady you can ignore this.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."