[Elecraft] K2 VCO Alignment not going well...

[David Pratt]

Terry -
A suggested mod (by Holger DL4LX on 18/7/02) is to remove C70 (4.7pF) 
completely and to fit a 10pF across C72 under the PCB.  Tests have found 
that this arrangement gives a more suitable range of VCO voltages across 
the bands.  Too high a VCO voltage will result in a chirpy note on CW.

73

David G4DMP

In a recent message, Terry Bassett <mutabut@net66.com> said....
>Hello All,
>
>       I am at the VCO Alignment stage. Two bands give high readings and I have
>checked parts identities and placement. I have pulled out T5 and T7 and redid
>them.
>
>
>here are my readings:
>
>80M 3500  2.03     4000    6.00
>40M 7000  1.64     7300    3.23
>30M 10000   2.81   10150    3.34
>20M 14000  2.45    15000   4.10
>17M  18000   8.44   18200   8.44
>15M  21000   2.36    21450   3.52
>12M   24800   4.05    25000   4.43
>10M   28000 8.44     28800    8.44
>
>       As you can see 17M and 10M are the problem.  I can see normal readings
>flashing on the LCD as I tune betweem the low end and high end of each of
>these bands.  But when I stop moving the tuning dial it goes back to 8.44v.
>       Also if if press the AGC buttom several times it will stay at an in-range
>reading and I can spin the tuning knob and the voltages will stay in range.
>If I press Band+ or Band- and then come back to the same band, the voltage
>will settle at 8.44.
>
>       I checked things over and over and am about out of things to look at.
>Do any of you have a fresh idea of what or where I should look?