[Elecraft] VCO Alignment on K2 7109

[Don Wilhelm]

  Ed,

The fact that your voltage on 80 meters goes from 6 volts to something 
below 2 volts may indicate a problem with varactors D23 through D26 (the 
group of 4) - check to be certain they are MV209 and that all are 
correctly oriented and well soldered.
Check the orientation and soldering of D21 and D22.
Next check the soldering of relays K13, K14 and K15 - make certain you 
did not miss soldering pin 1.
Then check the values of C71 through C75.
Schematic for the RF board sheet 1 shows the VFO range select area, and 
the Relay Table and VCO Table shown on the K2 Schematic Key page may be 
required to check the operation of the relays for each band and the 
capacitors used for each band.

Since you have 8 volts at R30 on bands other than 80, make certain you 
do not have any solder bridges between pins of the relays - be certain 
C72 is the correct 270 pF value (marked 271).

You may have to re-do the 80 meter adjustment of L30 and/or T5 if you 
change anything.  Always check the 80 meter band first and then the 
other bands.

73,
Don W3FPR

On 6/5/2011 7:43 AM, EMD wrote:
> Hello Don,
>
> I have checked the values of c60 and 61 from L30, as well as c96, c95, c94,
> c93, c92 and c88 from U6 and they are all correct.  D21 and D22 are both
> V149SL.
>
> I don't know if you remember but while I was working on phase 2 I had an
> issue with a mix varactor diodes but that was in the crystal area and I
> swapped out the incorrect varactor.
>
> 73,
> Ed KE7HGA
>
> --
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