[Elecraft] KXPA100 Hi PA current ?

[Don Wilhelm]

Glenn,

What was the DC voltage at 100 watts keydown?
It should be 12 volts or greater - more is better, 13+ is good.

If the voltage drops, the current will increase (and I believe the 
efficiency decreases) to maintain your 100 watt output level.  More 
current, more heat.

An off center fed antenna may present a reasonable SWR, but SWR does not 
tell the whole tale.  OCF antennas are infamous for RF-in-the-shack 
problems, so you might have some RF floating around to create 'strange 
happenings'.

73,
Don W3FPR

On 6/1/2014 1:06 AM, WA7SPY wrote:
> I have had my KXPA100 for 5 months or so now. I have loaded the latest firmware Wayne sent out a few weeks ago for beta testing. My KXPA100 has the Automatic antenna tuner installed. I run the amp into a Carolina Windom 40 and the automatic antenna tuner works well using this antenna on all the bands except 160 meters of course. I normally don't operate on that band anyway.
>
> I was running the amp on 40 meters at 100 watts doing back to back rag chewing CW QSO's this evening. The amp shutdown and my KX3  display showed Hi PA current. The amp was very hot to the touch which makes me believe the amp had to shut down to protect the finals. The antenna SWR shows under 1.2. to 1. Is this normal behavior for the KXPA100?
>
>