My experiences with class E single ended amplifiers is similar to that reported
by Mal. The only caveat I would add is that you should be quite sure that you
have the right driving waveform. During my early experiments with a design
based on G3NYK’s spreadsheet I tried a sine wave rather than the square wave it
should have had. The result was lower efficiency and a short life for the FET.
John F5VLF
> On 26 Nov 2016, at 11:35, mal hamilton <[email protected]> wrote:
>
> Chris
> The Decca 5501 amp modules use a H bridge class D configuration followed by a
> series resonant PA circuit and this is probably one of the most reliable
> amplifiers about. Use suitable rated FET'S to give the desired RF output.
> Also the protection cct used avoids disaster in the event of an antenna
> failure short/open cct,
> I have built lots of class D 1Kw push pull amps over the years for LF/MF but
> they are vunerable to damage with load variations whereas the Decca bridge
> amps survive. I never had a failure with the Decca, and have been using them
> for many years.
> Another approach which is worth a consideration is the class E amp single
> ended, these are very reliable and avoids the crossover switching problems
> with the push pull system. Setting up procedure is critical but there after
> very stable,
> Hope these observations help you
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