[Elecraft] Linear PS Recommendations

Clay Autery cautery at montac.com
Thu Jul 21 14:39:35 EDT 2016


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



More information about the Elecraft mailing list