[Elecraft] KX1 hi current on 80 and power mod.

[Don Wilhelm]

> -----Original Message-----
  IMPORTANT...while troubleshooting with kx1
> out of case..use a low voltage (7 volts ?) and short transmission
> times.
>

Folks,

I would go a bit further and say NEVER operate the KX1 out of the case
without a suitable heat sink on the output transistor - no matter what the
supply voltage.

I have a 2 inch square of 1/8 inch aluminum that I have drilled and
countersunk a hole in for the mounting screw.  A spare thermal pad provides
the needed insulation from 12 volts (if you don't use an insulator and a
metal screw is used, a short to the 12 volt supply line will result).  If
the nylon screw is used, the thermal pad insulator should still be in place
because the heat sink will be 'hot' with the supply voltage.

With this simple little device on my workbench, I can operate the KX1 in
TUNE (with a 13.8 volt supply) long enough to make any measurements I need
and/or do extensive troubleshooting.  Check this heat sink occasionally, and
if it gets warm, give it a time to rest before continuing.

73,
Don W3FPR