On 2/24/2020 10:37 AM, Walter Underwood wrote:
Instead of a notch, I’d try low-cut and high-cut to narrow in on the signal.
Note that K1JT strongly advises to set wide bandwidth and let WSJT-X do the filtering in the digital domain. All it takes to make that work is to use the audio drive the way I've described.
Think about it this way. The A/D in the sound card is good for about 90 dB of dynamic range. The green bar tells us how far the signal level is from the BOTTOM of that range. Let's say that a strong signal is 50 dB over S9, and it takes over the AGC in your KX3. If the audio drive TO the computer sets the green bar to 30 dB, it would take a 20 dB over S9 signal to be within range of the A/D.
But if we set the green bar to 80 dB, S9 is still 30 dB above the bottom of the A/D, and at 6 dB per S-unit, we can decode signals down to S4 (or to S4 if you call an S-unit 5 dB).
73, Jim K9YC ______________________________________________________________ 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]
