[Elecraft] KLPA3A power transistor thermal stress concerns

[Wes Stewart]

Personally, I would, and do, avoid that region.  The difference in received 
strength between 10 and 12W is imperceptible if the HPA isn't installed. If it 
is installed, crank the power up to 20 or so and you're out of danger.

Wes  N7WS



On 10/24/2017 8:31 AM, Mike via Elecraft wrote:
> The K3/100 switches to the KPA3A at 12 watts.  So is there a 2w range
> (10-12w) where the KLPA3A is putting out unacceptable IMD?  Is there a way  to
> make the switch at 10w, or should we just avoid that 2w "danger zone"?
>   
> 73
>   
> Mike KD8RQE
>   
>   
> In a message dated 10/24/2017 10:56:38 A.M. Eastern Daylight Time,
> wes_n7ws at triconet.org  writes:
>
> The  K3/10 will output 12W.
>
> That said, based on IMD measurements I have  performed I would NEVER run a
> K3/10
> at 12W out.  Frankly, with my K3S  with the latest rev KLPA3A to keep 3rd
> order
> IMD below 30 dBc, I would  throttle it back even more above 18 MHz.
>
> Wes  N7WS
>
>