[Elecraft] Stinking KDSP2 cured

Allen Ward Allen Ward" <[email protected]
Sat Oct 11 21:23:01 2003


Report stinking (like epoxy or urea overheating) KDSP2 and difficulty
understanding  SSB with noise reduction on. Thanks to the help of Ken K3IU
(thanks Ken) with some measurements from his unit ( my current drain 86 ma
vs 63 ma in his) and the fact that R12 (43 ohm) was overheating.   I
rechecked all resistor placements and solder joints.  The problem was that
C16 (10uf) had a solder bridge across both leads shorting R13 (220 ohm) to
ground.  Hence the extra 23 ma.  This also messed up the switching of Q5 and
Q6 hence the terrible audio.
Things learned: my eyes like the rest of me are not too good anymore, and
never ignore a burning odor (learned a long time ago), old learning has to
be repeated and the schematic for the KDSP2 has printing that is TOO small!
73 Allen KA5N