Bob, This can usually be corrected (at the K3) by re-doing the power calibration steps, or by manually setting CONFIG:TXGN HP to a somewhat lower value. This adjusts the open-loop gain on a per-band basis, and should correct the overshoot. To change the TXGN HP value you have to first set CONFIG:TX ALC to OFF. Further details in the K3 owner's manual. If this doesn't do it, please contact K3 support.
73, Wayne N6KR On Aug 8, 2011, at 1:14 PM, Robert Redmon wrote: > Actually, I think my original message was misleading. The problem is > really the K3 with which I drive the KPA500, causing the overdrive > condition. When first transmitting, instead of putting out the set > power > (20 watts), my K3 generates significantly more (60 watts according to > the display on the KPA500 in standby). My KPA500 only requires about > 20 > watts to drive it to 500 watts on 10. Consequently, until the K3 > settles > down (a matter of a second or so), it is overdriving the > amp...significantly. > > 73, > > Bob K5SM > > On 8/8/2011 2:42 PM, Robert Garceau wrote: >> No problem on 10 meters on my #165 KPA500 >> W1EQ, Bob >> >> >> -----Original Message----- >> From: [email protected] >> [mailto:[email protected]] On Behalf Of Klaus >> Koppendorfer >> Sent: Monday, August 08, 2011 2:38 PM >> To: Robert Redmon; [email protected] >> Subject: Re: [Elecraft] KPA500 10 meter behavior >> >> yes kpa-500 serial 230 has exactly the same behavior >> >> ________________________________________ >> Von: [email protected] >> [[email protected]]" im Auftrag von"Robert >> Redmon >> [[email protected]] >> Gesendet: Montag, 08. August 2011 19:16 >> Bis: [email protected] >> Betreff: [Elecraft] KPA500 10 meter behavior >> >> I put my KPA500 on 10 today for the first time and noticed a rather >> unexpected behavior. Often, on the first character of transmission, >> the >> K3 drive power apparently spikes, driving the KPA500 to more than 700 >> watts. This seems to stabilize following that first dit or two, but I >> have to reduce drive to below 12 w before that behavior stops. >> Seems the >> 100 watt module in the K3 is behaving poorly. Anyone else noticed >> this? >> Doesn't seem to be a problem on other bands. (SWR is 1.3:1). >> >> 73, >> >> Bob K5SM >> ______________________________________________________________ >> 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 >> >> > ______________________________________________________________ > 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
