On Sun, 25 Mar 2001 06:55:48 -0500 "Alex Von Yonkers"
<avy@qwestonline.com> writes:
>
>Hmmm....Have you ever designed such a monster before Jeff?
>You realize you have to have variable Oscillator Frequency to be able to
>move eventual EMI from the Rx frequency. And this under Receiver
>Control.
>Unless you can design a real quiet (-100dBm EMI) 2-4KW switcher in the
>frequency bands of interest. This is not a trivial task :)
>
>Alex
>
>
Hi Alex,
I've been there with both SCR's & FET's -- at the 2 KW level.
The line side filtering is greatly eased (also the power factor!) if
one uses a modern PFC (Power Factor Correction) input stage.
The output stage can be easily implemented with one of the ZVS (Zero
Voltage Switching) controller chips that will eliminate a lot of the
spurious as well as providing voltage regulation. You will need to wind
a transformer for this... though at the power level you're considering it
could be an easy to fabricate coaxial design.
The output stage can be switched off in receive and the input stage
will kind of just idle without a load, so there is really no serious
noise problem, to your own receiver.
I can point you to a couple of references, if you are interested in
this approach.
73,
Marv WC6W 310 649 3111
*
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