[Elecraft] How hot is too hot

[Tom Hammond NØSS]

>I got the KPA100 running with only minor troubleshooting, and it seems to be
>running like a champ. Gave it a good workout in SS last weekend. But can't
>find anything on how hot is too hot on the heat sink.
>
>If I wait for fan to come on (whether set on normal or low/high) it seems
>like the sink gets pretty warm to the touch before the fan kicks in. The fan
>seems to cool it, hold down heat well. So for the contest I just switched it
>to High fan and let it run.
>
>But tonight in a casual QSO, top was hot again before fan kicked in. Is this
>normal, or should I be checking things twice?

As I recall, general rule of thumb:

   If you can place your hand (finger) on the heatsink and leave
   it there for 5-6 seconds without screaming, it's getting 'warm'.

73,

Tom  N0SS