[Elecraft] K3 low Power

[Don Wilhelm]

Martin,

I have to ask since you did not mention it -- did you install the PA 
jumper block after removing the KPA3?  If not, you need to do that.

As for operating the transistors in the Low Power PA getting warm - one 
should *never* operate the K3 in transmit with that bottom cover 
removed.  The cover serves as a heat sink.  Hopefully you have not 
already destroyed those transistors.

73,
Don W3FPR

On 5/12/2014 5:53 PM, Martin wrote:
> Elecrafters,
> a little while ago i had an issue with loss of rf-power.
> I thought i had found the problem. I hadn't.
>
> Symptom now:
> Power out only about 3 Watts.
>
> I removed the 100W-PA, changed the Menue to 'not inst'.
>
> With TUN PWR set to 12W i can achieve about 2.5W .
>
> Only 1 of the 3 Transistors on the low-Power PA gets warm during 
> (short) transmissions with the bottom cover removed.
>
> There are 2 RD15HVF1 and 1 RD06HHF1. How can i check if a transistor 
> is defective?
>