P3F> Intuitively, I feel that if shortening was as marked as the ARRL test
suggests, I would be able to perceive it.
Pilots are trained to trust instruments and not their eyes!
There is a lot of tech and psyhology involved in full BK CW. Initial key
closure has to change internal electronics from RX to TX mode. This
switching might be audible at low speeds. It often includes antenna relay
introducing the constant delay of about ten of miliseconds. ALC has to
establish proper power level while the previous RX AGC level should be
preserved or anulled in the case of fast AGC. RF which goes out is
different from the monitor audio tone. PTT makes a life much easier for the
rest of transmission but puts you in the broadcasting mode.
Psychologically one is very tense at the begining of transmission as you
must assure proper code. Subsequent elements are part of the rythm.
Separate RX might be used for TX monitoring but RF gain must be reduced in
order to prevent AGC interplay.
FT-1000 MP CW has 2 msec rise time but very sharp decay which causes wide
spectra. There is a proper shaping electronics around the final keyed
transistor but RF drive is closed too fast. Simple mod requires just adding
(instead of SMD changing) two 47 nF capacitors to achieve 3 msec built-in
decay. W8JI made a science from that...
73 de Mario, S56A, N1YU
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