I have done the mods and I'm running 00.30 and I'm still a bit off. My XG2 puts out ~-74dBm give or take a few tenths last time I measured it on our 80K spectrum analyzer and my combination reads -81dBm on the K3 with the ATU in bypass and no pre or att. PRE or ATT are correctly accounted for and the signal does not change if either are activated individually. Activating both at the same time causes the signal to increase by 1dB but operating in this condition would just be plain silly so I don't consider that a real world scenario. Engaging the tuner which is setup for my antenna at that particular frequency actually makes a change of 3dB. Again thats no fault of any of the equipment just something of interesting note...
~Brett (N7MG) On Fri, Aug 13, 2010 at 3:56 AM, Bill W4ZV <[email protected]> wrote: > > > Al Lorona wrote: >> >> I note my P3's amplitude readings are about 6 dB low-- that's with the IF >> output >> switched off. I'm not sure how to calibrate it. >> > > Have you done the IF OUT Gain Mod mentioned at the top of page 5 in the > manual? > > http://www.elecraft.com/K3/mods/IF_Output_Buffer_Gain_Mod_Rev_A.pdf > > Earliest P3 firmware versions had a gain error of ~10 dB but the latest > version (beta 00.30) is better. My P3 now reads -74 dBm for all > combinations of PRE/ATT on and off (using the XG1's -73 dBm setting). Once > Alan implements Amplitude Calibration we should be able to correct the > remaining errors. > > 73, Bill > > -- > View this message in context: > http://elecraft.365791.n2.nabble.com/P3-Power-measurement-with-the-P3-tp5419099p5419585.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > 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
