[Elecraft] K2: VFO control voltage problem.

[Don Wilhelm]

Thomas,

What is the voltage when you tune to 4000 kHz?  That is the starting 
point for adjustment and it should be near 6 volts. 

After obtaining 6 volts at 4000 kHz, do a quick check at 7000 kHz - that 
voltage should be in the 1.5 to 2.2 volt range if all is well.

After that, check the other band edges.

If the voltages do not fall in line as above, you have some 
troubleshooting to do.  In addition to T5, check the varactors to be 
certain they are the correct ones in the correct places, and that 
everything is soldered well. 

If you still have trouble, measure the VCO frequency with the internal 
counter probe connected to TP1 when you tune to 4000kHz and when tuned 
to 3.5 MHz and let us know what those frequency readings are as well as 
the corresponding R30 voltages.

73,
Don W3FPR

Thomas wrote:
> Hello.
> I know this has been covered before, but I could not find anything at this time.
> I have 7.56V on 30M, 20M, 17M, 12M and 10M both on low and high part of the bands.
> On 3.50MHz I can't get the VFO voltage above about 3V, same on 21MHz.
> On 7.0MHz I got aprox. 6V vhile on 7.3 I got aprox. 7,56V. 
> I have re-checked the capacitors C71 to C74 and the values are corect.
> I have vound the transformer T5 as on the drawing and several pictures on the internet,but it seems like it migth need another turn or 2?
>
> 73 de Thomas LA3PNA
>
>