[Elecraft] VCO test

[Don Wilhelm]

Gary,

You changed the probe for a known good one, and that was a wise first step.
Next wise step is to determine whether the counter components on the 
Control Board are working.  Try putting the counter probe in TP2, enter 
the menu and select CAL FCTR - you should see a frequency near 4915 kHz. 
  If you do obtain a reading, then your counter is working.  Also try at 
TP1, you should find a frequency between 12080 and 12100 kHz.

If you don't obtain any readings, can you temporarily swap the Control 
Board with a known working one?  If that Control Board allows you to 
obtain a counter reading, then try replacing Q9 and Q10 on your control 
board.  You can use 2N2222 transistors (borrow the two that you have not 
installed yet if you need to - then obtain replacements from 
mailto:parts at elecraft.com).

If your VCO is not working, let us know and we will try to trace it to 
the source of the problem.

73,
Don W3FPR

Ian J Maude wrote:
> Hi All
> 
> Up to Alignment test (p 60) onto the VCO test. So far all resistance 
> checks and previous tests check out within tolerance. Freq probe has 
> been replaced with known good one too.
> 
> Problem - with Freq counter in tp1 I should see 8-10 Mhz with freq on 
> about 4000.1khz. I do not. Display shows 00000Khz steady. Have re 
> checked and heated all connections, replaced Q17 (just in case) but 
> reading does not change.
> 
> Any pointers?
> 
> Thanks M0RGB Gary
>