I know this message is a bit old, but I've been too tied up with other
projects to read the reflector mail for the last two months (fyi - the
reflector generated over 2000 emails in the last 2 months).
The increased gain mod I did for the KSB2 was originally designed to
increase the transmit gain in SSB for a barefoot K2. The original K2 had
difficulty reaching 10 watts of power output in SSB on 10 meters. When you
drove the audio input harder to get to full power, the K2 would start to
clip on the audio peaks. This does not create a wider bandwidth signal
because the SSB modulator is followed by the SSB filter, but it does
increase the audio distortion. I added the extra emitter follower stage to
increase the overall IF gain in the SSB transmit signal path.
This mod should not be necessary with the KPA100, since it can reach full
power with only a few watts of drive. Some folks have reported that the
emitter follower stage can cause power output instability when the KPA100 is
installed. There is at least one fix around that reduces the gain of the
emitter follower stage by increasing the emitter resistor value and
apparently eliminates this instability. I would recommend that the emitter
follower gain stage not be used in a K2/100 since it does appear to cause a
stability problem, and there is no need for the extra gain on 10 meters.
-John
KI6WX
----- Original Message -----
From: "Roy Morris" <[EMAIL PROTECTED]>
Sent: Saturday, June 03, 2006 9:41 AM
I would like to hear from anyone who has K2/100s with both the unmodified
KSB2 and the modified KSB2 with the KI6WX 2N2222 amp mod (and 1.08
firmware). How does this mod affect mic gain and VOX operation? How does
the absence of this mod affect mic gain and VOX operation? Does the mod
help SSB modulation on 10 meters with the power level set at 5 watts? Do
you find this mod helpful at 100 watts? Thanks for your input. Roy Morris
W4WFB
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