Dear Mal, LF Group,
G3KEV wrote:
...>The beauty of CW and variations of the mode handled by a competent
operator is simplicity, just a basic TX carrier keyed on/off, basic RX just
a regen TRF device and a good pair of Ears. The appliance operator needs
computers, appropriate software and keyboard skills to try and achieve a
similar result, and often fails....>
Have you tried using "just a regen TRF device" on 136k and 500k? I have...
receiving amateur CW sigs on 500k with a simple regenerative RX is quite
feasible, although not very satisfactory if more than one signal is present.
On 136k, it does not really work, due to insufficient rejection of DCF39 and
friends, which just swamp the detector. Most people are actually receiving
CW with complex modern receivers, many using digital signal processing where
the signal has to pass through a computer before the competent operator can
listen to it.
If people want a simple receiver for these bands, try a "Softrock" or
similar. Used with a domestic PC and some of the excellent free software
that other appliance-operating amateurs have produced, this can produce very
good results. You can build one in a tobacco tin for a few pounds, in true
QRP style, although the same probably isn't true for the transmitter!
G3KEV wrote:
...>There is no substitute for a skilled radio operator to pass essential
short messages, which applies to most radio amateur communications...>
Well, we are amateurs, engaged in "leisure activity" and it is hard to think
of a time when an "essential" message has been passed by LF/MF amateurs -
life could go on without us, so this does not seem very relevant.
Cheers, Jim Moritz
73 de M0BMU
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