[Elecraft] KPA500 max heat sink temp?

[Jack Brindle]

I can confirm that KPA500 V1.00 firmware, which was the first released, had a max temperature of 90 degrees C. This has not been changed in any subsequent code.

As for the input power, the amplifier has improved over time. My original prototype KPA500 requires power in the range described (about 35 - 40 watts), while my new one (just over a year old) needs about 20 or so watts. Both are great amps!

73!
Jack, W6FB


> On Jul 8, 2020, at 1:00 PM, William Hammond via Elecraft <elecraft at mailman.qth.net> wrote:
> 
> Hi Eric, My manual (revision B, 2011) that came with my SN 0149 says 90C maximum, page14 in the specifications.  It also says drive power 30-40 watts for 500 out and I have never beed even close to that, usually 22-26 watts drive.  
> 
> FYI,
> Bill-AK5X
> 
>> On Jul 8, 2020, at 6:00 AM, Eric Norris <norrislawfirm2 at gmail.com> wrote:
>> 
>> I just read in the current KPA500 Manual that max heat sink temp is 90C.
>> Is this true for my first-year production KPA500?  I seem to remember
>> somethink like 75C.  I cant find my old manual.
>> 
>> 73 Eric WD6DBM
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