[Elecraft] K2 SSB ALC Problem

[Don Wilhelm]

Sanjin,

What setting do you have for the SSBA menu parameter - for the MH2, it 
should be set at 1.

Does your K2 have any additions to the KSB2 board, such as the KI6WX 
increased gain mod?  If you don't know, open the K2, remove the KSB2 
board and check for an additional transistor mounted on the board - it 
will be near U5 and could be either on the top or bottom of the board.  
If that mod is present, *and* especially if you have the KPA100 (either 
internal or external), there are changes to the ALC circuit on the KSB2 
board that must be made to keep from "slamming" the ALC.

There is also the possibility that you have an ALC problem on the KSB2 
board - if it is a very early KSB2 board, there were some changes made 
to improve the IMD for data modes that changed the ALC component 
values.  Download the current KSB2 manual from the Elecraft website and 
compare the values of the components in the lower left corner with the 
values you have on your KSB2 board.  That is one downside to buying a 
used K2, you can never be certain which changes have been installed 
without inspection, unless the seller provided you with complete and 
detailed information about changes.

73,
Don W3FPR

Sanjin Tajic, E71DX wrote:
> Hi All,
>
> I have a K2 which I bought used. I never really used it on SSB but from time
> to time would like to.
>
> The problem is when I transmit (Mic is the Elecraft MH2) I get very hard ALC
> action which jumps to full ALC scale reading.
>
> I tried to "inject" (via the Mic in a quiet room) a constant modulation and
> even with this "constant" source I get a very erratic ALC action.
>
> I get this ALC action with all Mic-gain and Mic-comp settings - more or less
> ALC respectively.
>
> In all cases the actual Power-out is as it should be and I have no problems
> with the power control neither in CW or SSB.
>
> This was present from the first day I got it but till now did not really
> bother me much.
>
> Options installed are: KSB2, K160RX, KNB2, KAF2, KIO2, KAT2, K60XV, KBT2.
>
>
> Thanks in advance for all tips!
>
> Sanjin, E71DX
>