I use a single ended E pa and it is vy robust. I use a good LPF and the 2nd
harmonic is not a problem.
mal/g3kev
----- Original Message -----
From: "Stefan Schäfer" <[email protected]>
To: <[email protected]>
Sent: Tuesday, January 12, 2010 10:42 AM
Subject: AW: LF: PA0 into Alaska 600m
Hi Johan,
What are you planning? This sounds like QROO? Why using a push-pull class E
stage when a single stange can do it?
I am interested! :-)
Stefan/DK7FC
________________________________
Von: [email protected] im Auftrag von Johan H. Bodin
Gesendet: Di 12.01.2010 07:56
An: [email protected]
Betreff: 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/.
|
