[Elecraft] K-2 Part II test and alignment problem

[David Woolley (E.L)]

Larry Wright wrote:
> 
>  
> PLL Reference Osc Range Test yields 12.099 - 12.086 = 13 Khz range.  
> But  the VCO Test yields 5.535 Mhz instead of the expected 10 to 12 Mhz 
> reading.

That suggests a band switching problem, or problems with the VCO band 
range capacitors or varicaps. Could you possibly have spun the dial to 
get on band, rather than used the bandswitches.  If so, you may need to 
do a direct frequency entry.

>  
> The K-2 receives every 5 Khz .   The problem seems to me to involve the 

What do you maan by that (although it may be a symptom of not having 
calibrated the reference oscillator)?

> 12 Bit DAC (U5).  Have resoldered the pins to it.    Pin 8 is 5v, but 
> pin  7 stays at 3.4v at all times.  Pin 1 on U6 stays at 7.6v.   (the 8v 
> Regulator output is 7.6v)  The 7.6v output is present to the PLL ref. 
> osc circuit.  Turning the dial has no effect on the output of the DAC.  
> The PLL Reference osc stays at 12.099 Mhz.   

But you previously said that the reference oscillator range check 
passed, which indicates that control voltage is being varied.  I think 
this symptom arises from a failure to calibrate.



-- 
David Woolley
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