A Field Guide to the DM-780 Digimode Traces

Mike, K6MKF – k6mkf ('at' sign) hotmail.com

April 19, 2011

What the heck is that mode? I’ve often seen a trace on the waterfall that I couldn’t identify. By the time I tried decoding it in a few different modes, the signal was gone. A lot of traces I can identify: PSK31, PSK63, PSK125, MFSK16, RTTY, but a lot more are still mysteries.

So I thought I’d create this document from screen shots of the transmissions that DM-780 can produce. I’ve organized it by width of signal as the width is the first thing I notice. This document does not contain traces of all the digimodes. New modes are being developed all the time. The traces shown here are the ones I could generate from my DM-780 installation. No QRM was created making these traces as RF Output was zero into a dummy load.

Trace Widths 31Hz – 125Hz

PSK31 – One of the most common modes:

QPSK31 (USB & LSB) – PSK31 with error correction; looks less symmetrical than PSK31:

FSK Hell 105:

Slow Hell:

PSK63 – Twice as wide and twice as fast as PSK31:

QPSK63 (USB & LSB) – PSK63 with error correction; looks less symmetrical than PSK63:

Throb 1:

Throb 2:

ThrobX-1:

ThrobX-2:

FELD HELL X5:

PSK125 – Four times as fast and wide as PSK31:

QPSK125 (USB & LSB) – PSK125 with error correction; looks less symmetrical than PS125:

Contestia 4/125:

DominoEX-4:

MFSK-4:

RTTYM 4/125:

FSK Hell 245:

Throb 4:

ThrobX-4:

Thor 4:

Olivia 4/125:

Trace Widths 250Hz – 500Hz

Contestia 4/250:

MFSK-8:

Olivia 4/250:

MFSK-16:

Olivia 8/250:

RTTYM 4/250:

RTTYM 8/250:

RTTY 45:

RTTY 50:

RTTY 75:

FELD HELL:

Contestia 8/250:

Olivia 8/250:

Thor 8:

Thor 16:

DominoEX-8:

DominoEx-8:

DominoEx-16:

Contestia 4/500:

Contestia 8/500:

Contestia 16/500:

Olivia 4/500:

Olivia 8/500:

Olivia 16/500:

RTTYM 4/500:

RTTYM 8/500:

RTTYM 16/500:

MFSK-32:

MT63 500:

Hell 80:

Trace Widths 1000Hz – 2000Hz

MFSK-64:

Contestia 8/1000:

Olivia 8/1000:

Contestia 16/1000:

Olivia 16/1000:

RTTYM 8/1000:

RTTYM 16/1000:

RTTYM 32/1000:

Contestia 32/1000:

Olivia 32/1000:

MT63 1000:

Feld Hell x9:

MT63 2000:

Contestia 8/2000:

Contestia 16/2000:

Contestia 32/2000:

Contestia 64/2000:

Olivia 8/2000:

Olivia 16/2000:

Olivia 32/2000:

Olivia 64/2000:

RTTYM 8/2000:

RTTYM 16/2000:

RTTYM 32/2000:

RTTYM 64/2000:

A Field Guide to the DM-780 Digimode Traces

Mike, K6MKF – k6mkf ('at' sign) hotmail.com

April 19, 2011