[Elecraft] KLPA3A power transistor thermal stress concerns

[Don Wilhelm]

Nick,

It all depends on your perception of "fairly hot".

My 'rule of thumb' is that if you can hold your fingers on the surface, 
then it is not too hot.

73,
Don W3FPR


On 10/24/2017 7:27 AM, Nick - VE3EY wrote:
> I have a K3s/10 (12 watt version) which I intend to use in the upcoming cq
> ww cw contest.  This unit does not have KPA3A power brick and cooling fans
> installed.
> 
> While doing some trial runs I noticed that the area around the KLPA3A power
> transistors is getting fairly hot after prolonged contest use.  My guess is
> the transistors are working harder when used as finals.  The rig needs to
> produce between 6 and 12 watts to properly drive the SS amp I intend to
> use.