[Elecraft] K2 - VCO-Test (Alignment an d Test, Part II)

[Masleid, Michael A.]

> The usual problem with the VFO is T5 not making proper connection due =
to improper stripping of the leads
...
> to add a turn relates to the voltage on R30 not quite making it to 6 =
volts.

> Don Brown

Dave, since you have too much voltage, and too low a frequency, then =
adding turns isn't going to fix it.
If you've checked out what Don pointed out, but didn't turn up anything, =
note the following:

>> The frequency is not stabil - it changes very quickly about +/-10 Hz.

This is normal, the counter twiddles the last digit if the frequency is =
between 10 Hz values.

>> When I tried to adjust the Voltage at R30 I got  constantly 8.2V. I =
can turn on L30 - there is no
>> effect.

The voltage won't change because the PLL control voltage is trying to =
raise the frequency, but it
can't produce more volts.  If the frequency changes by many percent when =
you adjust L30, something
is wrong with T5.  If the frequency changes only a little, look for too =
much capacitance down there
on K13, K14, K15.  C72, on K13 is the only one that should be in the =
circuit.  Make sure that C72 is
270 pF, not 0.01 uF.  (It takes a lot of capacitance to drop down to 1.3 =
MHz)

73,
Michael, AB9GV