Mike, Your base K2 power output on the higher bands is the root of the problem. The KPA100 has a 10 dB gain, so 8 watts in gives you 80 watts out.
I would suggest you check the winding and position of T2 in the base K2. It should be wound just like the diagram in the manual and mounted 1/16 to 1/8 inch above the board. 73, Don W3FPR On 8/29/2010 1:44 AM, Mike and Alicia Fanning wrote: > Hi all, > I have just finished building and testing my KPA100 kit, and the power > output seems low (87-89 Watts) on 10, 12, and 15 meters. Is this > typical? I have triple checked that the parts are installed properly > in the 10-15m low pass filter stage, and everything looks good there. > After verifying the LPF was okay, I went back and measured output > power from the K2 without the KPA100 installed. Here are the > numbers. The first column is the band in question, second is the > transmit power without the KPA100 installed (barefoot), third is with > the KPA100 installed but powered through the original low power DC > input (amp installed but bypassed), and the fourth is with the KPA100 > installed and powered through the KPA100 high power DC input (amp > installed and active). > > 10m 8W 7.5W 87W > 12m 9.75W 9W 87W > 15m 11.5W 10.5W 89W > 17m 12W 11W 106W > 20m 12W 11W 100W > 30m 13W 11W 106W > 40m 14W 11.5W 107W > 80m 13.5W 11W 105W > 160m 12.5W 12W 111W > > When the KPA is hooked in but bypassed (column 3), why is the power > output lowered? Is it because of the second set of low pass filters > (on the KPA100 board) coming in line? I was surprised to see the > transmit power level drop so much if this is the cause. > > Are my barefoot numbers fairly typical? Looks like the KPA is giving > me pretty consistent gain, so do I need to be looking upstream > somewhere in the original K2? If so, why the big jump on the KPA100 > output between 15 and 17 meters? > > Any thoughts or ideas appreciated. > > Thanks and 73, > Mike Fanning, K4GU > K2 #5882 > ______________________________________________________________ > 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
