Brian, I have a friend who has an Astron RM-35A power supply. I downloaded the schematic for him a year or so ago, & I kept a copy. All of the Astron linear power supplies have the same basic circuit.
Looking at the schematic shows that applying a voltage to the output terminals while the power supply is off will reverse-bias the base-emitter junction of the 2N3771 pass transistors. The absolute maximum reverse voltage rating of the B-E junction of a 2N3771 transistor is 5 Volts. Applying 13.8 Volts to the output with the AC power off has the potential of breaking down the B-E junction of the pass transistors as well as the B-E junction of the TIP29 driver transistor. It is not worth the risk. 73, Ray, K9DUR http://k9dur.info _______________________________________________ FlexRadio Systems Mailing List [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kc.flex-radio.com/ Homepage: http://www.flex-radio.com/ Message delivered to [email protected]
