[Amps] More pictures...

[David Cutter]

I was very pleased to read that you believe a way forward with a solid state 
design is to use off line power, ie do the insulation in the rf stage.  My 
ignorance with this is how the extra insulation might degrade transformer 
performance.  Modern high voltage transistors from the likes of IXYS might 
be the way forward, or perhaps cheap high voltage switching MOSFETs.

David
G3UNA
>
> Well... I'm still on the lookout post for some legal limit SS PA design
> that has advantages over the age-old and well-established ones, which
> typically use 50V MOSFETs of ancient Motorola lineage, in class AB. The
> advantages could be in obtaining high efficiency by running class E or
> class F with envelope restoration, or at least in doing away with the
> power supply by running directly off the line, and using low cost
> transistors. If nobody comes up with something like this soon enough, I
> guess I will! We need to innovate!
>
> But right now I'm playing with PICs rather than RF MOSFETs. There's less
> to blow up with them. When I get fed up with those little cute digital
> toys, I might return to the big and serious world of PA development! :-)
>
> Manfred.
>