[Elecraft] KPA1500 Drive Power

[K9MA]

Mine seems to have fixed itself. Output was dropping from 1500 to about 
1100 W when it warmed up, but I just operated an hour in the CWT, and it 
never dropped below 1400.  That was consistent with the tests I ran the 
other day.  I had just come up with theory that the power drop was 
caused by something ELSE in the amp heating up, not just the heat sink 
for the MOSFET's.  That might have explained why the problem didn't show 
up in my brief tests. Now I just don't know what's happening.  More data 
required.

73,
Scott K9MA


On 6/5/2018 23:24, Bill Johnson wrote:
> Roy, I owned and will soon have Kpa1500.  Yes power will drop if heat becomes an issue and you will fault.  The amp logs the condition when it faults.
>
> Have a great day,
> Bill J
>
> ________________________________
> From: elecraft-bounces at mailman.qth.net <elecraft-bounces at mailman.qth.net> on behalf of Roy Morris, Jr. via Elecraft <elecraft at mailman.qth.net>
> Sent: Tuesday, June 5, 2018 2:36:52 PM
> To: Elecraft Reflector
> Subject: [Elecraft] KPA1500 Drive Power
>
> Noone has responded to my previous inquiry about the KPA1500 power drop-off due to heat.  I would like to know if the KPA1500 power output actually drops off due to heat build-up or because the SWR display was erroneously showing a power drop before it was fixed.  Thanks,  Roy Morris W4WFB
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-- 
Scott  K9MA

k9ma at sdellington.us