[Elecraft] Yet another KX-1 Question

[Don Wilhelm]

Dan,

The trimmers will only change the receiver front end tuning, they will not
have any effect on transmit.
For transmit power output problems, the first thing to check is the Low Pass
filter inductors.  As a first step, make them look like the inductor
diagrams in the manual, then use small 'tweaks' from there.
Also check T1 for the proper number of turns on both windings.

Remove the tuner (install jumper) and operate the KX1 directly into a 50 ohm
dummy load when testing for power output.  Monitor the power output with an
RF Probe (or 'scope) connected across the dummy load.

Unless you have some major error in the transmit components (wrong resistor
or capacitor values), there is little that can go wrong with the transmit
path.  You can signal trace through the transmmit stages with an RF Probe
comparing the RF Voltage levels on 40 meters with those on 20 meters to see
where the signal is significantly lower on 20.

73,
Don W3FPR


> -----Original Message-----
>
> I've been following the discussion on low power output from the KX-1
> with interest. My problem is a little different, though. With a 12V
> gel cell, mine outputs 3.5 - 4 W on 40m, but I'm getting a watt or
> less out on 20m. Receiver sensitivity seems lower, too.  I've tried
> readjusting the trimmers, but that didn't seem to help much.
>
> 73!
>
> Dan KB6NU
>