[Elecraft] KPA-1500 on digital modes

[Larry (K8UT)]

Pete,

I don't run my amp at full legal limit on digital modes, but typically set the input power for about 1000 watts output. One of the interesting characteristics of the amp is increased efficiency as power increases. At 600 watts efficiency is only 38%, whereas at 1000 efficiency increases to 50% and at 1500 watts to 60%.

(see screenshots)

  -larry (K8UT)

------ Original Message ------
From: "N4ZR" <n4zr at comcast.net>
To: "Elecraft List" <elecraft at mailman.qth.net>
Sent: 2019-08-29 07:59:23
Subject: [Elecraft] KPA-1500 on digital modes

>Elecraft's published specs rate the KPA-1500 for 1500 watts output on all modes.  In prepping for this weekend's contest, I've been running it at closer to 700 watts, because I've found that even just running on CW, with its much lower duty cycle, my amp reaches 70C quickly.  I don't do that much digital contesting, though, so I'm wondering whether 1500 watts output is on digital modes is realistic or a recipe for trouble.
>
>--
>73, Pete N4ZR
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