[RTTY] Automatic Threshold Correction

[Kok Chen]

For the technically inclined person interested in Automatic Threshold Correction for FSK, I wrote a short note from back in 2008 that shows a small "nit" with standard ATC and how it can be corrected:

http://homepage.mac.com/chen/Technical/FSK/ATC/index.html

The above page has a figure on what a Mark-only demodulator looks like (and points out why Mark-only demodulation is better than conventional ATC if the space signal has faded completely).

No, understanding the above won't help you get a better contest score :-) :-).  But you might be able to include it in the next modem that you build to get a teeny weeny better copy for electively fading signals with really low SNR, HI.

73
Chen, W7AY