[Elecraft] Mods

[Mike Harris]

Hi,

Just to add to the knowledge base.  Whilst waiting impatiently for the
second of the two packages containing my KPA100 I have been catching up on
outstanding modifications to K2 #1400.

1.  Replaced C19 of the KAF2 with 56pF and now the clock shows no noticeable
time drift over five days checked against the BBC World service time signal.
It was over a second + a day.  WWV on 10MHz is almost useless here in the
Falklands due to half of the Amazon basin using it as a chat frequency.

2.  Did the PSK31 ALC time constant component changes on the KSB2.
Interesting to note that if giving a whistle into the mic. to illuminate a
bar of ALC, the bar pulses a few times after the whistle stops.  Possibly
this is something to do with the CPU scan of the ALC voltage which is being
held up by the longer decay time constant.  Correct?

3.  Did the BPF and VFO ALC mods.  Fortunately these components arrived in
the first KPA100 package, along with the handbook, heat sink, PCB, shield,
strip of relays and half a sheet of sandpaper.

4.  Did a complete realignment of all the BPF's.  Much, much easier to do
with an analogue power meter than the K2 display or digital VOM with RF
probe.  I guess we are designed to respond to movement rather than track
jittery numbers.

If I have to wait much longer for the second KPA100 parcel I'll probably end
up doing the other KSB2 related mods.

Regards,

Mike VP8NO (IOTA SA-002)
GQRP 10148
K2 #1400