[Elecraft] K2: Attempting K2 SSB modulation and ALC mods, but board too old?

[Eric Swartz WA6HHQ - Elecraft]

Andreas, are you measuring SSB using a peak Watt meter? If you are just measuring it on an average reading meter, your power level will always appear lower than a continuous CW carrier.

73,
Eric

www.elecraft.com
_..._


On Sep 30, 2012, at 11:03 PM, Andreas Hofmann <Andreas.Hofmann at microsoft.com> wrote:

> Don (and others),
> 
> One problem down, one to go.
> 
> I believe I have solved the modulation issue.  I started fresh and did all alignments, from Freq calibration, PLL, Filters, BFO passband (with your excellent descriptions on how to use Spectrogram).  Especially the BFO was way off. I am not sure if these settings somehow deteriorate overtime or what happened.  I know that stored digital values cannot simply change, but analog components can and maybe that's what it is. Or (not impossibly) I screwed up big times 9 years ago when I built the K2.  I listened in a SDR and really noticed how the BFO passband changes the overall modulation.  Great.
> 
> Now, my SSB power output is still not very good.  I would think that this is an ALC issue.  On the same frequency on 40m, using a dummy load, I can get 110 W out in CW, but about 40 W in SSB (and me screaming into the mike), with ALC showing four LEDs on the right display. On 20m, I get about 40 W out without an ALC.  This is with both the Elecraft MH2 and the Elecraft Heil pro 2.
> 
> So, I think I am kind of back to my original issue of trying to attempt the QRP Projekt mods for more mike drive and ALC circuits.  Or are there other things I should be checking first?  Is there a way to temporarily "disable" the ALC to see if the output is artificially controlled