Jim; Make sure the transformer is bolted down appropriately. If it works loose then it will cause the hum.
Jack Brindle, W6FB On Jun 11, 2013, at 7:51 AM, Jim Miller <[email protected]> wrote: > I leave my KPA500 back panel switch in the ON position most of the time and > use the front panel switch to bring it to life. > > However in even when in the "Front panel off/Back panel on" state the > KPA500 will occasionally hum for a few seconds. > > Is this normal? Any suggested causes to worry about? > > Thanks > > jim ab3cv > ______________________________________________________________ > 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 ______________________________________________________________ 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
