[Elecraft] Output power on K2 not stabel

[Don Wilhelm]

Dick,

Sorry, but that does not help a lot - the operation in TUNE that you 
describe in normal.  TUNE (with the KPA100) normally controls power at 
20 watts.  If you enter TUNE and then turn the power control, it will 
try to produce the power that is set on the power control knob.

The gain of the power control loop is increased (over the base K2 gain) 
when the KPA100 is present and the power control set for greater than 11 
watts - so the fact that this problem does not show up at low power is a 
not unusual.  If the gain of your KPA100 is greater than the average, 
you may notice this power control loop oscillation problem.

Try increasing RF Board R98 to see if the power control oscillation 
settles down.

73,
Don W3FPR

Dick Grolleman wrote:
> Hi gentelmen
>
> More info
>
> I have been testing my K2 on the power issue.
> I have the following findings
> It is stabel on low power. I set it to 5 watt, press tune and it is 
> stabel. turn the power up to 50 watt, and it goes from 42 to 50. stop 
> the tuning, press tune again and the power is 28 watts and going down 
> to 20. Turn it op to 50 again, and stop tuning. press tune again after 
> a few seconds and again is 28 watt and goes down to 20. turn it up 
> again, and it repeats again, so i keep increasing the power. but if it 
> is on 50 watt is is quit stabel. Then start transmiting, and the power 
> varies from 40 to 70watt.
> never noticed this before as it is the first time I use the radio witn 
> an amp. But I does not matter if the amp is on or not. works fine on 
> 100 watt
>
> Maybe this helps.
>
> many thanks 73 de Dick
>