Hello Mal,
with my 136kHz PA (variant of the G3YXM Class-D push-pull) I get 450W
output with 56V/9.5A supply, thus 85% efficiency.
I once tried a 50W class-E PA and got over 90% efficiency with correct
load (50 Ohm). But the efficiency of the class-E was very sensitive to
mismatch and for higher power levels the required values of L,C and
supply voltage were rather inconvenient.
Regarding components: I use coils wound on a thin PVC former (with
sufficient thick wire) and polyprop capacitors.
As both in class-D and class-E amplifiers the FET's are used as switch
(on/off device) they must be fast enough en have a low on-resistance.
The higher the frequency the faster it needs to be.
73, Rik ON7YD
Quoting hamilton mal <[email protected]>:
Hi all
Class D and E amplifiers are supposed to give around 80/90 % efficiency. Has
anyone actually achieved these figures. It seems anything above 60% is hard
to arrive at using normal coils/capacitors.
73 de Mal/G3KEV
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