[Elecraft] re 10m instability fixed....I hope

[ken cubilo electric]

ok guys here's what i did re the 10 meter ssb oscillations. They were
being caused by stray rf from the kpa100 getting into the k2 main board
and I suspect via way of the ssb module. I took G3PJT's advise and
installed additional shielding around j2 the coax connector on the
kpa100. I checked out the placement of l10 and that was ok. I used braid
from a piece of rg/8m cable and using two strips soldered on the shield
across the opening for j2 and resoldered at the first screw holding the
shield closest to j2. I then tried out the rig and found it had quieted
down quite a bit but was still getting a bit of rf in the modulation but
no longer getting oscillations. I added a 2nd strap from the ground
point of the ksb2 module to one of the screws on the kpa100 shield
directly above it making it as short as possible with access through the
side panel and bingo she is clear as a bell. I am not going to do the
happy dance just yet as this type of problem being so border line from
full stability sometimes has a tendency to return. Anyway I tested her
out on 10m this morning working a few dozen stations and doing lots of
whistling and cannot get the rig to take off now.. Thanks to all who
responded to this. It looks like the fix might be to make the kpa shield
a real tight fit to j2 with cutouts for j2s mounting nuts. I might also
add that since making this mod the current drawn from the power supply
for 100w output has dropped 1.5 amps and the high speed fan takes a bit
longer to kick on now. before a single 3 by 3 cq call on 10m would
generate enough heat to kick er on. Lets knock on wood

73 ken w8ob #2864
owner of the best transceiver ever made