[Elecraft] KPA500 Power In Digital Modes

[Joe Subich, W4TV]

 > Since the K3 turns off the final stage when below 13 watts, does
 > that mean running 10 watts is a bad choice since that's running
 > the lower power stage at near maximum?

As it relates to that part of the distortion caused by compression
or clipping in the amplifier chain (IF-> Low power amplifier -> PA),
running the K3 at 10 watts is probably worse than running it at 20
watts.  I don't have specific data on the particular devices used
in the K3 but in general IMD is minimum around 80% of maximum rated
output.

73,

    ... Joe, W4TV


On 2014-11-19 6:50 AM, Ken wrote:
>
> On Nov 10, 2014, at 7:30 PM, Joe Subich, W4TV wrote:
>
>> Depending on the crest factor (peak to average ratio) of the mode
>> in use, the average power from the KPA-5000 should be kept 6 to 10
>> dB below the rated maximum (e.g., 60 to 150 watts) just as a 100W
>> transceiver should be kept between 10 and 25 watts average.
>
>
> Since the K3 turns off the final stage when below 13 watts, does that mean running 10 watts is a bad choice since that's running the lower power stage at near maximum?
>
>  From a cooling perspective alone, I have often wondered if it's better for a K3 to be run at 15w rather than 10.
>
> Ken WA8JXM
>
>