[K2] C22 has no effect

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[K2] C22 has no effect

Steve Kavanagh
I just acquired a second hand K2 (my second one) and upon going thru the operation in detail I noticed that it was somewhat off frequency.  WWV at 10 MHz is received best (on USB using the CW filter - there is no SSB board) at 10,000.96 MHz and adjusting C22 has no discernible effect on the beat note while listening to WWV tuned slightly off frequency.  I took the control board out and saw that C22 is soldered on both sides.  But the only possible cause I can think of for this behaviour is that C22 is either not making contact (bad solder joint) or is defective.  Am I missing any possibilities ?
 
73,
Steve VE3SMA
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Re: [K2] C22 has no effect

Don Wilhelm-4
Steve,

C22 has no effect on the received frequency or the beat note during
normal operation.
The setting for C22 is only used during a run of CAL PLL and CAL FIL
when the frequencies (actually equivalent DAC values) are stored in EEPROM.
Once that has been accomplished, the 4 MHz reference oscillator serves
only as the clock for the MCU and for that function, the exact frequency
is not important.

If you want to do a calibration run on your K2, I suggest you review the
K2 Dial Calibration article on my website www.w3fpr.com.

73,
Don W3FPR

On 11/6/2014 3:50 PM, Steve Kavanagh wrote:
> I just acquired a second hand K2 (my second one) and upon going thru the operation in detail I noticed that it was somewhat off frequency.  WWV at 10 MHz is received best (on USB using the CW filter - there is no SSB board) at 10,000.96 MHz and adjusting C22 has no discernible effect on the beat note while listening to WWV tuned slightly off frequency.  I took the control board out and saw that C22 is soldered on both sides.  But the only possible cause I can think of for this behaviour is that C22 is either not making contact (bad solder joint) or is defective.  Am I missing any possibilities ?
>  
>

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Re: [K2] C22 has no effect

Steve Kavanagh
Thanks for setting me straight, Don and Mike.  I think have the hang of it now...calibration is much better now - though I still may want to refine it a bit.  Though, I didn't seem to be able to make the N6KR method work on WWV at 20 MHz - couldn't get a frequency match.  But it's ok at 15 MHz.  

73,
Steve VE3SMA
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