Don and others who responded - thanks! (1) its hard to fix what isn't broke (2) i have been using this rig many years .... (3) somehow i falsely believed i could tweak the power knob BEFORE hitting TUNE (4) maybe i hard time believing i assembled this board without any issues! (5) the two button routine to transmit full power is actually nifty !
my rig does produce 100 watts! i do notice the finals are too hot to touch when transmitting, but they cool in a few seconds when transmit ceases. maybe this is normal (i have never touched an operational 50 watt device before). i guess i need to find where the K2 will tell me its temperature to see if all is well. 73, curt --- Don Wilhelm <[EMAIL PROTECTED]> wrote: > Curt, > > How are you attempting to initiate transmit? If you > ae pressing TUNE, > then 20 watts is what should be produced - the > KPA100 firmware limits > TUNE to 20 watts. If you need to try at a higher > power than that, you > must press TUNE and DISPLAY together. > > OTOH, if you are already doing TUNE/DISPLAY, then > check the KPA100 LPF > toroids for the correct number of turns - count the > nmber of times the > wire passes through the center of the core. > > 73, > Don W3FPR > > Curt Milton wrote: > > I did some additional troubleshooting, but maybe > there > > is nothing unusual in these bias measurements? > > > > Bias Rx Tx > > D11 13.7 0.7 > > D12 0.7 129 > > D13 13.7 0.2 > > D14 0.7 129 > > Q1/2 base 0 0.6 > > > > Still puzzled as why rig is limited to around 20w > > output. Current draw is proportional to RF power > > output, as above 20w setting rig will neither draw > > additional current nor output additional power. > > > > --- Curt Milton <[EMAIL PROTECTED]> wrote: > > > >> Has anyone experienced this problem, or know if I > >> should troubleshoot the bias, input, or output > >> circuitry. All is well with the low power bypass > >> path, and rig seems to work up to around 25 watts > >> output. > >> --- Curt Milton <[EMAIL PROTECTED]> wrote: > >> > >>> Date: Sun, 27 May 2007 12:08:40 -0700 (PDT) > >>> From: Curt Milton <[EMAIL PROTECTED]> > >>> To: [email protected] > >>> Subject: [Elecraft] KPA100 Failing to Produce > High > >>> Power > >>> > >>> All has been well up until now, including > setting > >>> the > >>> bias per instructions. Without PA's my bias > >> current > >>> was 330 mA, so I successfully set it for 730 mA > >> with > >>> the PA's. > >>> > >>> I had adjusted R26 for 5w and got the VSWR > sensor > >>> zeroed. During my high power test (into a > matched > >>> antenna on a clear channel into a good antenna) > my > >>> VSWR is reading 1.2 on the K2 and similar on my > >>> external meter. When I transmit the PA devices > do > >>> get > >>> very hot (too hot to touch after about 10 > seconds) > >>> but > >>> they quickly cool (maybe around 5 seconds or > less) > >>> after transmit ceases. > >>> > >>> Here is the behavior i am getting. First column > >> is > >>> K2 > >>> power setting (on 20m), second is what the K2 > >> reads > >>> on > >>> transmit, and third is my meter. My meter is > not > >>> state of the art but it is reasonable with my > >> other > >>> rig. > >>> > >>> K2 Setting K2 Indicated Meter > >>> > >>> 15 15 20 > >>> 20 20 28 > >>> 25 25 30 > >>> 30 23 28 > >>> 35 22 30 > >>> 40 22 35 > >>> 50 23 32 > >>> > >>> Thinking that maybe R26 was way off, i set the > K2 > >>> for > >>> 40 watts and tried to adjust R26 to read 40 > watts > >> - > >>> no > >>> this got me no where. > >>> > >>> I tried to operate on different bands with two > >>> different antennas. Same impact on all bands, > >>> except > >>> it has even lower output on 10m. > >>> > >>> Troubleshooting suggestions appreciated! > >>> > >>> 73, Curt > >> > >> > >> > >> > > > ____________________________________________________________________________________ > >> Be a PS3 game guru. > >> Get your game face on with the latest PS3 news > and > >> previews at Yahoo! Games. > >> > http://videogames.yahoo.com/platform?platform=120121 > >> _______________________________________________ > >> Elecraft mailing list > >> Post to: [email protected] > >> You must be a subscriber to post to the list. > >> Subscriber Info (Addr. Change, sub, unsub etc.): > >> http://mailman.qth.net/mailman/listinfo/elecraft > > >> > >> > >> Help: http://mailman.qth.net/subscribers.htm > >> Elecraft web page: http://www.elecraft.com > >> > > > > > > > > > > > ____________________________________________________________________________________Ready > for the edge of your seat? > > Check out tonight's top picks on Yahoo! TV. > > http://tv.yahoo.com/ > > _______________________________________________ > > Elecraft mailing list > > Post to: [email protected] > > You must be a subscriber to post to the list. > > Subscriber Info (Addr. Change, sub, unsub etc.): > > http://mailman.qth.net/mailman/listinfo/elecraft > > > > > Help: http://mailman.qth.net/subscribers.htm > > Elecraft web page: http://www.elecraft.com > > > ____________________________________________________________________________________ Need a vacation? Get great deals to amazing places on Yahoo! 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