KPA-100 Output

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KPA-100 Output

Roy Morris-6
When I drive my Alpha 99 with the K2/100, the K2 POWER control has to be set to approx 17 watts with the TUNE button to put out 1KW.  (A 15 db gain with 17 watts input should put out approx 550 watts.)  It seems that the ALC may be engaged in TUNE but may be breaking down in SSB.  However, I receive good QRO audio reports with no reported problems.  
A few years ago I installed the ALC mod to the KSB2 board but removed it when I installed the KPA-100.  
I noticed that Don replaced C31 (.033 200V) with a .22 in the T-R Switch to tame the sidebands.  
I wonder if I should re-install the ALC mod or replace C31 with a .22 capacitor on the KPA-100 board.  My K2/100 has been completely updated with the latest firmware and revisions.  This includes latest revisions to the KPA-100.  Roy Morris  W4WFB
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RE: KPA-100 Output

Don Wilhelm-3
Roy,

The change in C31 was to cure an OSCILLATION (not sidebands) - and it should
ONLY be done IF the KPA100UPKT is installed.  In fact it is currently being
shipped with the KPA100UPKT.  DO NOT CHANGE C31 UNLESS YOUR KPA100 meets ALL
the conditions.

I suggest that you do re-install the ALC mod on the KSB2. and see if that
settles things down for you.

When evaluating the K2/100 performance for power control, remember that the
granularity of control is about +/- 2 watts at 11 watts or greater (+/- 0.2
watts < 10 watts).

73,
Don W3FPR

> -----Original Message-----
>
> When I drive my Alpha 99 with the K2/100, the K2 POWER control
> has to be set to approx 17 watts with the TUNE button to put out
> 1KW.  (A 15 db gain with 17 watts input should put out approx 550
> watts.)  It seems that the ALC may be engaged in TUNE but may be
> breaking down in SSB.  However, I receive good QRO audio reports
> with no reported problems.
> A few years ago I installed the ALC mod to the KSB2 board but
> removed it when I installed the KPA-100.
> I noticed that Don replaced C31 (.033 200V) with a .22 in the T-R
> Switch to tame the sidebands.
> I wonder if I should re-install the ALC mod or replace C31 with a
> .22 capacitor on the KPA-100 board.  My K2/100 has been
> completely updated with the latest firmware and revisions.  This
> includes latest revisions to the KPA-100.  Roy Morris  W4WFB
>
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