Guido, The BFO RANGE is not sufficient to set the BFO far enough from the carrier and permit a tone of 2295 Hz on both sidebands. You will need a minimum range of 4590 Hz (and likely at least 500 Hz more will be required for a comfortable margin). Your range is only 4180 Hz.
You could try increasing the BFO range or reset all the RTTY BFOs to center the filters at 1125/1295 rather than 2125/2295. This will require tuning the RTTY signal offset by 1 kHz and most sound card programs will properly handle that - if you are using a hardware TNC that requires the 'real' 2125/2295 audio tones, you will have to increase the BFO range further. 73, Don W3FPR ----- Original Message ----- > As I wrote in my last message, on K2 #4334 I was not able to calibrate the > narrow filters on RTTY normal to center high tones (about 2.2KHz): I reach > about 1.6KHz and then the BFO resets to the intial frequency. > It happened only on RTTY normal (LSB), on RTTY reverse (USB) I was able to > calibrate correctly the filters to match the 2125/2295Hz tones. > During the BFO calibration, I had to add 68pF and 100pF in parallel with > C174 and C173 to have the correct BFO range (4916.77 KHz - 4912.59 KHz), do > you think that I can't calibrate the filters because the BFO limits are not > yet enough (too high or too low)? > Any suggestion? _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
