[Elecraft] Thermal control for Q1 / Q2 in KPA100?

[David Lankshear]

I was playing around with the KAT100 a couple of nights ago and was leaving the K2/100 on tune for periods of 15 - 20 seconds at a time (20W) at intervals through several bands.  After a few minutes, the whizzer fired up its engine, so if your average Tx power is 20W then you have maybe 5 mins before the little hovercraft starts up.

I note it blows air INTO the KPA, but there doesn't appear to be much by way of provision for the warmed air to get out, so I guess oscillators are going to move around quite a bit when the warm air circulates around and around.  Maybe a nice, quiet ex-computer muffin fan sitting on top of the heatsink might be a better way of cooling the PA?

73 Dave L  G3TJP