[Elecraft] K2/100 + KSB2 + MH2 questions

[email protected] [email protected]
Tue May 28 23:25:01 2002


On Tue, 28 May 2002 [email protected] wrote:

> John, KC4KGU wrote:
> 
> "If anyone out there is running a K2/100 + KSB2 + MH2 combo, I am
> seriously interested in which settings you use for SSBA and SSBC."
> ==========
> If the MH-2 doesn't have much output, first you might want to change R14
> on the SSB board from 1k to 5.6k or 6.8k, or even 10k.  This will
> increase the amount of mic audio getting into pin 4 of the speech
> compressor IC (U3).  Also, set SSBA to "2" to increase the mic gain about
> 10 dB avove the "1" setting ("3" is the same as "2" with the current
> firmware).
> 
> I use a cheap $5.00 dynamic element and had to change R14 to 5.6k to get
> enough mic audio to trip the VOX.  I have SSBA set to "2".  Monitoring
> myself in another receiver, I decided that the SSBC setting of "3-1" was
> best.  I've received rave reviews of my on-air audio, no matter what the
> band on both LSB and USB.
> 
> 73, de Earl, K6SE


OK.  This may answer one of my questions.  The MH2 appears to have pleanty
of drive though, on some bands.  It is strange.

With SSBA at 1 and SSBC at 1-1, I can get TX drive MORE than I need on
some bands.  Perhaps what is needed is a compressor/limiter vs just a
compressor.  I'm not certain that we don't have a limiter in the KSB2 but,
if in fact we did, and it could be adjusted via a variable resister to
limit MAXIMUM TX audio drive from the KSB2 to the K2, we could then tinker
with the SSBA and SSBC to our hearts content.  The worst thing that could
happen then is "scrunched up, make your ears bleed, compressed to
death" audio.

Based on the fact that I can achieve plenty of drive on SOME bands (too
much in some cases), do you still think that I need to adjust the resister
values?

73 de John - KC4KGU
K2/100 #2490