[Elecraft] KPA500 efficiency

[Yngvi (TF3Y)]

Hi folks.

I'm wondering about the efficiency of the KPA500.
Mine, which I assembled a few days ago seems to exchibit 76-78% efficiency
on CW. Admittedly I havent tested it on SSB.

The HV stands at 57.6V under load with current at 14A. Hence 806W input.
Measured output using my LP-100A at 630W. Drive for this 29W on 12m.

What class is the amplifier operating in on CW? Does the class depend on
mode? I'm using the KPAK3AUX cable.

The operating temperature seems to remain close to 50C.

73, Yngvi TF3Y
http://www.tf3y.net