Mike Dennison, G3XDV
LF Amateur Radio

QRSs - Stretching the limits

Reception of extremely slow CW (QRSs) is achieved using my 200MHz Pentium computer under Windows95. The AF output of the IC-706 is plugged into the sound card. I run the waterfall display program Spectrogram by Richard Horne, downloadable from the author's site. Spectrogram ran straight away on my computer without me needing any knowledge of how it interfaces with the sound card. It is therefore ideal for getting started on this mode. Having been a CW enthusiast for several decades, I was astonished at how this program can produce 100% reception of signals which are totally inaudible by ear. It is also astonishingly good at producing signals when the QRN makes conventional CW impossible. See gallery of displays of Spectrogram plots.

New Developments

An interesting variant on QRSs is Visual CW (VCW). A new DSP program for use with QRSs and VCW has been developed by I2PHD. It is called Spectran. More details and a Beta version to download from Alberto's web site.

e-mail: mike.dennison@ntlworld.com

Last updated 4 June 2000