[Elecraft] K2 160m VFO problem

[Ray / SM0XLP]

I've just installed the 160m option to my (second) K2. However, the VFO
refuses to work, The problem sems to be in the PLL / VCO area.
Monitoring TP1 shows no ouput on 160, all other bands OK. Reference
oscillator at TP3 is fine on 160 and tunes perfectly.

 
As far as I can see in the PLL / VCO area, the only component that is
excusively used on 160 is C75. I know from experience of my first K2,
that if C75 becomes O/C, the oscillator range changes but continues to
work. However, I changed C75 (twice) in any case but to no avail. The
relays are OK, I can see that when K13 is reset (for 160) I get
continuity up to T5. D21 / 22 seem to be OK. If I measure the VCO
control voltage at R30, I get +8V which changes if I tune but goes
immediately back to 8V. 

Can there be any other cause than C75 / relays?

 

73 de Ray / SM0XLP