Am 30.08.2012 17:09, schrieb Markus Vester:
[...]
- DK7FC was active on a nearby frequency during most of the night. In
conjunction with the noise blanker the RX is desensitized by the a
nearby strong signal. The problem is exacerbated by high density of
keyclicks in Opera (5 to 8x more than QRSS), and that most seem to
apply hard keying. Trying to interleave operating times (eg. even vs
odd days, or hours) is probably not a satisfactory solution.
Sorry for that Markus. You know, the AM modulator is very near to the
top of my Todo list and the first half of the circuit is working now
(BTW not using a PWM with a TL494 but a VCO using a CD4046. That works
well). So it sould be possible for me to reduce key click of signals
generated in SpecLab, i.e. QRSS/DFCW/HELL/Beacon-Cw, soon. If my clicks
would be reduced, would then the NB performance come back to 100%?
However Opera directly keys the PA using the COM port and an external
signal generator (SL!). This is one of the main advantages of that
software and why Graham calls it CW replacement mode (of course CW
cannot be replaced, it is a language for its own).
Recently we discussed about transmitting the OP code by playing an image
in slow hell. Or alternatively a file which can be loaded ito the
arbitrary waveform generator of SLs signal generator could play the code
in SL. Of course the software could be run simultaneously. Maybe even
the Opera TX-button can be virtually pressed by a DOS command so the
announcement of that transmission is is sent to the web? The mode and
band information must be sent too, to coordinate the software with the
actual TX then. That makes it more and more complex.
So what might be the solution for those who use an external signal
source and just key the PTT by the COM port using Opera software? Maybe
a special higher order shaping using hardware, like in a CW HF TRX?
Possible!
73, Stefan/DK7FC
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