Tony, The KX3's temperature stability is specified at +/- 1 ppm typical over 0-50 C. That's +/- 14 Hz on 20 meters. Normally the short-term stability would be far greater than this. However, during long key- down periods there is some heating of the RF board, which includes both the PA and oscillator circuitry.
We included closed-loop temperature compensation for this effect in hardware and firmware. Normally this compensation is entirely sufficient, but apparently it doesn't meet WSPR/JT65 requirements. I should be able to provide a user-settable fine compensation value in the menu, although it would be a bit of trial and error for the user to determine the optimal value. Wayne N6KR Tony Estep wrote: > ....KX3 frequency stability on receive seems fine, as evidenced by > nice level > lines on the graph... > The frequency stability requirements both of WSPR and JT65 are > considerable. WSPR transmits 4-frequency FSK, with the tones > separated by > only 1.5 hz. The whole bandwidth is 6 hz. ______________________________________________________________ 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
