----- Original Message -----
From: "John Rabson" <[email protected]>
To: <[email protected]>
Sent: Wednesday, August 04, 2004 9:49 AM
Subject: LF: CW and other modes
A few thoughts on why we are doing this:
It seems well established that, if you (i) have enough real estate to put
up
a mast or masts of useful height and install a good earthing system and
(ii)
live in a quiet location, it is relatively easy to work interesting
distances using hand-speed CW. I believe Mal has shown this.
For many of us, none of the above desirable conditions obtains, but by
collaborating with one another we have accumulated a body of knowledge of
various techniques which enable us to make a better job of communicating
in
unpromising circumstances. People have worked distances which, when our
LF
allocations were first released, seemed impossible. If we had been able
to
borrow a redundant antenna at GBR, working across the Atlantic with it
would
have been a fine achievement but it would not have been anything like as
great an achievement as doing so from a domestic garden.
I feel we should avoid becoming obsessed with DX in the sense of distance.
The abbreviation also has a connotation of difficulty. As people may be
aware, my main interest in LF is for underground communications. I would
be
delighted if I could work through two or three kilometres of limestone on
136 or 87kHz (the latter being a common cave radio frequency) using SSB.
Currently we have achieved something like half that.
We should not decry technical aids such as computers. Sometimes they make
things possible which otherwise just cannot be done. People doing
moon-bounce or meteor-scatter seem happy to use such things (it is a long
time since I heard complaints about people using high-speed tape recorders
when working MS). Why should such devices be unacceptable at LF?
Finally, for those who feel that we have reached a dead end, may I suggest
a
challenge?
Analogue speech transmission in the form of single sideband has been used
in
the amateur service for more than 50 years. It is time we found something
that is less greedy of bandwidth, preferably something that would work
within a 100Hz channel so as to allow amateurs whose LF licenses limit
their
bandwidth to take part.
I doubt is there is anything available or in the pipe line to beat CW when
it comes to B/Width and conveying a message the most economical way.
73
John G3PAI
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