Andy, Johan
The Class E AM guys do this. The amplifier below will do 500 watts at carrier and 150%+ modulation
effortlessly.
http://www.classeradio.org/class_e_8_fet.pdf
Jay W1VD WD2XNS WE2XGR/2
----- Original Message -----
From: "Johan H. Bodin" <[email protected]>
To: <[email protected]>
Sent: Tuesday, January 12, 2010 1:56 AM
Subject: Re: LF: PA0 into Alaska 600m
Hi Andy,
I tried to connect two class E stages in push-pull and it worked as
expected. This was a QRP experiment on 160m but I see no reason why it
shouldn't be scalable. The even harmonic cancellation of the symmetrical
design is welcome since the drain waveform contains quite a lot of 2f.
Each side is designed for half the output power into some R and then the
matching transformer is designed to have 2R looking into the primary.
The two series resonant tanks can be combined into a single one having
half the C and twice the L (as in the attached picture).
Who will be the first to try a QRO version of this amplifier? :-)
73
Johan SM6LKM
Andy Talbot wrote:
All designs & ideas for a 1kW+ Class E PA gratefully accepted :-)
I do have a 50V 25A PSU, so it 'might' even be feasible.
Two big meaty FETs in parallel may cope. There's an article in the
latest QEX, just arrived, that appears to run class E stages in parallel
- but its part of another concept, not targetted at high power /per-se/.
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