Thanks Myron... Haven't cracked the case yet, but will check and verify...
______________________ Clay Autery, KY5G MONTAC Enterprises (318) 518-1389 On 7/21/2016 7:41 AM, Myron Schaffer wrote: > Jim and Clay, > > It used to be that way....the RS linear models could not tolerate external > voltage present when unpowered, not anymore. Astron has incorporated > back-voltage protection through incorporation of some diodes installed in key > locations to prevent this. > > You can verify if your supply has this modification by looking at the circuit > board and see a 1N4001 type diode soldered across 2-pins (can't remember > which ones off the top of my head) of the IC voltage regulator LM-723 chip > and others hung in various places to protect the pass transistor as well. > Usually soldered to the solder side of the circuit board so they are easy to > spot. I can't remember is there were some small capacitors added as well. > > Any newer (like newer than 1990) linear Astron will have these installed. > > Myron WVØH > Printed on Recycled Data ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
