Re: 811A first light

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Brent Turner by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bturner-at-apc-dot-net>

Malcolm -

OK, sort of a tuning stub line of sorts.


Tesla list wrote:
> 
> Original poster: "Malcolm Watts by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <m.j.watts-at-massey.ac.nz>
> 
> Hi Brent, all,
>                 There is an interesting variation which I recently
> read about in a book on SMPS design which no-one seems to have
> mentioned on the list. This is class F and is considerably more
> efficient than class C. At this stage, I'm not sure whether it is
> applicable to TCs but looking at the circuit configuration suggests
> it is. The author was discussing resonant SMPS topologies and looking
> at RF circuits. There is an interesting catch to it though.
>       The nub of the idea is to run an oscillator (in the author's
> case it was a solid state device) in what looks like class C with a
> resonant tank drain (plate) load but with a 1/4 wave delay line run
> between the drain and the tank. The line is used as a PFN and allows
> the power device to run with squarewaves rather than haversines.
> Basically the line is loaded with a high end impedance (parallel
> tank) and as we all know, a quarterwave line has resonances at f/4,
> 3f/4, 5f/4 and so on (I know that the tssp modelling gives slightly
> different values for a TC resonator) with the result that the line
> presents a more-or less constant impedance to a squarewave source at
> the driven end. Something I'll look into one day if I ever get the
> time.
> 
> Regards,
> Malcolm
> 
>