As a side note to this topic, I found it interesting to see how the MCW was produced in the LF NDB Aircraft Beacon transmitter that I modified to be a linear amp for the 500-KHz ARRL Experimental Program.
It was common for them to have CW that shifted 400-Hz upward in frequency, but instead of AM tone modulating a carrier they ran two xtal oscillators: One as set on the carrier frequency and ran continuously and a second xtal oscillator set a at f1 = fo +400 Hz and was keyed by a CW memory keyer. This resulted in both "carriers" being transmitted by the linear amps as CW modulated USB + carrier. On an AM receiver it produced 400 Hz MCW. For my use I disabled both xtal osc. and disconnected the CW keyer ckt. I substitute the TEST signal from my K3 for the oscillator carrier. The rest of the transmitter is linear amplifiers. I can drive the 100w 500-KHz xmtr with only 0.1 mw and in any mode that is possible on the K3. However we are restricted to CW, QRSS, psk-31 and its variants, and WSPR. Our 15-KHz wide band is not sufficient to support SSB and is not allowed. 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com EME: 144-1.4kw*, 432-100w, 1296-testing*, 3400-winter? DUBUS Magazine USA Rep [email protected] ====================================== *temp not in service ______________________________________________________________ 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
