Hello LF-Group,
last night (couldn't sleep and was looking out for VE1ZZ ...) I looked a
little bit over the fence and read some of the LowFer's messages. Obviously
QRSS has found wide acceptance in the US now and, considering the 1 Watt tx
input (!) and 50 ft antenna length limitations, remarkable distances of
over 1000 miles have been achieved using this technique.
You find some of those messages under:
http://www.qth.net/archive/lowfer/lowfer.html
Lyle, K0LR (the "king of LowFers" as someone called him in a message) has
compared various modes, (mixing a signal with real noise) and came to the
following conclusions:
- normal CW (12 WPM) -18 dB (level below a certain reference
level)
- PSK31 -15 dB
- BPSK (MS25) -18 dB
- BPSK (MS100 ET1) -24 dB
- BPSK (MS1000) -33 dB (howver: long time needed to
synchronize)
- MFSK8 -18 dB
- QRSS (0.4 WPM, with Spectran) -27 dB
- QRSS (0.4 WPM, with CRUNCH) -33 dB
you can find more about this test under:
http://www.computerpro.com/~lyle/weaksigs/weaksigs.htm
Les, N1LF (nice callsign!) is now a strong supporter of QRSS, what Dave,
G3YXM provides for us (always the latest LF-news, under
http://www.wireless.org.uk/index.htm), Les provides for the LowFer beacon
community in the US (http://www.highnoonfilm.com/xmgr/)
Best 73
Geri, DK8KW (W1KW)
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