I'll place my bets on WOLF getting through QRN when QRSS60 or even a dead
carrier can't be seen. Not long after Stewart introduced us to WOLF, Lowfer
station TEXAS was beaconing with this mode. I received good copy 5 nights in a
row when the QRN was very bad. I looked back at my sent mail and found one
message dated 21 March 2001. Here is a sample of what I copied every night over
this approximate 1600 KM path:
t: 960 f: 0.000 pm: 496 jm:173 TEXAS AGGIE 79 -
t:1056 f: 0.000 pm: 496 jm:173 TEXAS AGGIE 79 -
t:1152 f: 0.000 pm: 496 jm:173 TEXAS AGGIE 79 -
t:1248 f: 0.000 pm: 505 jm:173 TEXAS AGGIE 79 -
t:1344 f: 0.000 pm: 508 jm:173 TEXAS AGGIE 79 -
Dex
Rik Strobbe wrote:
Hello John, Dave,
I believe that it might be difficult to compare QRSS and WOLF as their
effectivity also depends on propagation conditions.
As WOLF is repeating the message over and over at a rather high speed it
can take advantage of short propagation peaks, this is not the case with
QRSS where the message is sent a single time at a very slow speed.
At the other hand QRSS might be better when propagation is rather stable
but very weak (or for surface wave propagation).
73, Rik ON7YD
At 09:57 12/01/2004 -0500, you wrote:
>Dave,
>
>We did some tests a couple of years ago involving two similar stations near
>each other that were about 1800 km from me. One ran QRSS60, the other WOLF.
>I think we did the tests for about a week, and found similar results.
>Neither had a clear advantage over that period. The conclusion was that the
>effectiveness of WOLF was about the same as QRSS60.
>
>While our QSO of yesterday did not fully exercise WOLF's capability, do
>realize that we were receiving 15 characters in a 20 minute period. QRSS60
>can't do that!
>
>As originally conceived by Stewart Nelson, the "reference channel" could be
>used to exchange signal report information. Neither that nor real-time
>decoding has been realized, however. It does remain an interesting mode,
>with a number of limitations as listed in Alan Melia's message of this
>morning. For U.S. Lowfers, bandwidth is not an issue, and the potential for
>anything but very local interference is limited.
>
>I do believe that gps-locked slower BPSK has more potential at LF, and am
>slowly working on getting set up for that. Underline the word "slowly,"
>though!
>
>John Andrews, W1TAG
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