Hi Eric Thanks for the email. It's not a problem..... really. In fact I'm now seriously thinking of buying a 2nd kpa500 amp for SO2R!
Cheers Ken..G0ORH Sent from my iPhone On 3 Aug 2011, at 16:55, "Eric Swartz - WA6HHQ, Elecraft" <e...@elecraft.com> wrote: > When the back panel switch is on, the low voltage power supply for the front > panel is still on, allowing the microprocessor to read the front panel > 'power' switch and talk over RS-232. A low level of power supply hum from > this small transformer is totally normal in this case. Of course, turnig off > the rear switch on the KPA500 shuts down everyhting. Its perfectly OK to use > the rear switch as the main on/off power control. > > The KPA500 front panel power switch is a 'soft' switch that controls the HV > supply relay etc. This allows remote control over RS-232 to power up/down the > amp etc. > > 73, Eric WA6HHQ > > --- > www.elecraft.com > > > On 8/3/2011 1:09 AM, Ken Chandler wrote: >> Hi >> I took part in IOTA contest at the weekend in the unassisted category, CW, >> high power. >> The KPA-500 was used for the first full 24hrs contest here with M3i >> call-sign and I did give it a darn good work-out end result performance was >> just fab. >> No hang-ups, instant power, band change, big pile-ups lots of QSO's LOTS of >> fun. >> It just loofed along, the fan came on occasionally but was not loud, my PC's >> fan is louder than the amp. >> HOWEVER >> after the contest, pc switched off, k3 on, amp still on in standby mode, >> Their is a HUM from the amp and was fairly noticeable. >> Turning off the rear switch cured it!!! >> Perhaps one for the engineers to look at, as I'm sure they will, and are >> already on the case!!!! >> >> Ken..G0ORH / M3i KPA-500 sn 212 >> >> Sent from my iPhone >> >> >> >> >> >> On 3 Aug 2011, at 07:08, Klaus Koppendorfer<k...@ccf.net> wrote: >> >>> discussion is drifting away to amplified speakers but there is realy a >>> problem with >>> HUM comming from KPA500 >>> >>> 1) HUM during transmit >>> 2) HUM somes sometimes when the KPA500 is off, but on line and backswitch on >>> >>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> 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:Elecraft@mailman.qth.net >> >> 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html