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Old November 27th 03, 02:00 PM
Ashhar Farhan
 
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"The Eternal Squire" wrote in message ...

I'd then create 8 class E amplifiers that put out 1/8w, 1/4w, 1/2w, 1w, 2w,
4w, 8w,
and 16 watt outputs for the same signal; modulating each one as CW in
accordance
with the audio bit.

I'd combine the outputs through a power combiner.

Questions:

1) Would this scheme be possible for creating SSB by parallel switching of
CW
amplifiers in accordance with a digitized audio signal?


nope, you will instead need to apply simultaneous frequency modulation
to the carrier as well as amplitude modulation.

2) Would I need to create assymetrical power combiners to combine the
amplitudes
of the different signals, or could I get away with simply making a
symmetrical
8-way combiner.


you will need an infinite way combiner, the easier way is to frequency
modulate the carrier so that it shifts to wherever you want the
carrier to be and control the envelope (this is a white lie, the
acutal explanation is a little deeper).

the dsp software required is not going to be easy. i have written a
dsp shell for the sound card, you can download from
http://farhan.net.co.nr and play with it. once i am finished with my
VHF transceiver i plan implement a hilbert transform using this shell
and make a simple SSB exciter with it.

- farhan