[Elecraft] KXPA100 70 to 80w out Max with KX3 drive at 15W???

[Bert]

That power supply should be adequate, if it's working properly.
Bert VE3NR


On 2022-10-18 9:26, Kyle Krieg wrote:
> Astron SS-30M-AP
>
>
> What Astron power supply are you using?
>
> John KK9A
>
> Bert ve3nr wrote:
>
> It seems your power supply doesn't have the capacity to deliver enough
> current.
> At 100W output the current draw from the PS should be closer to 20 Amps.
> Bert VE3NR
>
>
> On 2022-10-17 15:03, Kyle Krieg wrote:
>> * Hello all,
> *>>* I used my KXPA100 this past weekend and noticed some lower than normal
> *>* output on both SSB and CW.  Sitting on the bench today I've noticed that
> *>* I'm only putting out around 70 to 80W max where I used to push close to
> *>* 100w in previous outings.
> *>>* I tested the drive of the KX3 to find that to be 15W max, so that is good
> *>* and spot on.  I've checked the power setting output on the KX3 to drive up
> *>* to 110W.  I've powered the KX3 from both the back of the amp and an
> *>* external power supply with the same results.  The KXPA100 power is from an
> *>* Astron power supply.  On key down it gives it about 11A's of power.  DC
> *>* doesn't drop below 13.5 on key down with the amp on while it's pushing the
> *>* 72 W output. I've hooked up the KXPA100 utility and everything seems to be
> *>* working correctly with no faults found.  Short jumpers were used (less
> *than
>> * 2ft) with quality cable from back of the KXPA100 to the Bird wattmeter
> *then
>> * to a HF dummy load.  SWR is flat on all bands.
> *>>* Here is the power output per band on CW keydown.  The KX3 display is
> *>* showing 110W output.
> *>>* 160m : 80w
> *>* 80m : 78w
> *>* 60m : 73w
> *>* 40m : 72w
> *>* 30m : 80w
> *>* 20m : 78w
> *>* 17m : 92w
> *>* 15m : 85w
> *>* 12m : 80w
> *>* 10m : 80w
> *>* 6m : 76w
> *>>* These numbers match between the windows utility and Bird wattmeter.
> *>>* Thoughts?
> *>>* Kyle*
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