[Elecraft] KPA-1500 Power Output Variation

[K9MA]

Concerning the output variation, I’ve noticed that when I change bands while the amplifier is hot, the output on the new band starts out high, then gradually drops. This would seem to indicate that the LPF is heating, and that the loss in the filter is several hundred Watts. That’s no big deal if the filters are properly cooled, as they apparently are, but still requires manually riding the power control.

73,

Scott K9MA 

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Scott Ellington

 --- via iPad

> On Aug 26, 2019, at 7:34 PM, Bob Wilson, N6TV <n6tv at arrl.net> wrote:
> 
> As for KPA1500 output power variation with temperature, it is annoying, and
> it seems to vary from KPA1500 to KPA1500, perhaps depending on how many
> other devices or heat sources are located near the ventilation holes.