I've just run my K3 at 70 Watts into a 50 Ohm load, 14.020 MHz. Results were spurs at +/- 11.9 KHz which are between 103 and 106 dB down. The noise at 7 KHz out from the carrier is 106 dB down, even at 50 WPM keying (internal keyer). There was a spur 263 KHz up which was 98 dB down.
On 21 MHz there is a fixed spur on transmit at 21.028 MHz, it's still 94 dB down, no sign of the +/- 11.9 KHz spurs. Tuning the K3 across the band while transmitting and watching the signal (both 20m and 15m) didn't produce any odd spurious signals, except those noted above. Measurements done with a Microtelecom Perseus receiver and 50 dB attenuator. The Perseus has a similar specification to a spectrum analyser and used direct A/D conversion without mixing. 73 Dave, G4AON K3/100 #80 =============== Mike VP8NO wrote: For what it is worth. Just done a quick test with my K3/K2 combo. K3 14020kHz. 50W into my beam. K2 with no antenna connected receives a signal at S9+20 on the S-meter. Keying at 14013.67kHz and 14026.38kHz was heard. Additionally I heard signals at 14007.24kHz and 14000.99kHz, didn't tune further above the test signal. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
