Easy. Put a decent scope on the RF envelope. 73,
Hank, W6SX On Monday, November 10, 2014, Joe Subich, W4TV <[email protected]> wrote: > > > My K3 increases power by 10% when in Space as opposed to Mark. > > Two things here ... 10% is abut 0.4 dB. How did you measure the power > difference and did you do so with an instrument with enough resolution > to accurately measure that difference at the power level you were using? > For example a Bird Wattmeter can't possibly measure with that level of > accuracy nor is one likely to be able to read an analog meter that > closely. > > I have measured my K3 on RTTY with a wattmeter traceable to NIST and > specified for 3% accuracy and have done so at four specific power > levels (25, 55, 80 and 105 Watts) to eliminate any ALC non-linearity > or PA compression from consideration. The specific Mark/Space power > levels were measured by placing the rig into transmit in FSK_D mode > with the FSK input closed (Mark), measuring the power output for a > given power setting, then opening the FSK input and noting the PO > (and change). > > In all cases, the difference between MARK and SPACE was less than 2% > (less than the meter's specified accuracy) and at two power levels (55 > and 80 W) the measured difference was less than 0.2W (<0.2 dB at 55W). > > These measurements were made with standard "High tones" (2125/2295 Hz) > and the K3 was equipped with the optional 2.8 KHz, 8 pole IF filter. > > 73, > > ... Joe, W4TV > > > On 2014-11-10 8:42 PM, Bill Lewis wrote: > >> I am looking for information on how to eliminate incidental AM when using >> FSK-D. >> >> My K3 increases power by 10% when in Space as opposed to Mark. >> >> Thanks much, Bill, W8NN >> >> >> >> >> ______________________________________________________________ >> 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 >> Message delivered to [email protected] >> >> ______________________________________________________________ > 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 > Message delivered to [email protected] > ______________________________________________________________ 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 Message delivered to [email protected]
