[Elecraft] k2-test & align Part 2

Don Wilhelm w3fpr at earthlink.net
Fri Apr 20 18:52:32 EDT 2007


Certainly Jesse,

The most likely thing that is wrong is T5.  Make certain you have the 
correct number of turns (count the turns that pass through the center of 
the core, not complete 'wraps' as you would for a selonoidal inductor). 
  Check T5 carefully for properly stripped and well soldered leads.  You 
should see a bit of the tinned lead surface above the board - if not, it 
is suspect and should be removed and re-tinned.

Once T5 is proven to be OK, set the slug of L20 2 to 3 turns from the 
top of the can and then see if the voltage reduces any as you tune down 
the band toward 3500 kHz (it should).  If it does, the VCO is working OK 
and the problem is with the overall inductance of T5.  Start at the 
point where the voltage is 6 to 7 volts, then squeeze or spread the 
turns of T5 to make the voltage lower - move the frequency up until it 
again is close to 7 volts and squeeze/spread again until you can get 
about 6 volts when you are tuned to 4000 kHz.  Check all the other bands 
at the low end and adjust L30 to bring all bands above 1.5 volts 
(usually occurs at 7000 kHz) and below 7 volts (usually the highest is 
4000 kHz).

If you have installed the rework eliminators and changed C71 to 120 pf, 
then the procedure is a bit different, set D19=y in the menu and do the 
whole thing again - in fact, if that is the case, you will have to 
re-visit the VCO voltage alignment when you install the K60XV - the 
K60XV portion of the rework eliminators is *NOT* plug and play!

73,
Don W3FPR

Jesse & Nicky wrote:
> vco alignment-p 61 adjust slug L30 until voltage at R30 reads 6.0 volts.  I read 7.945 volts and does not change as you tune L30.  I have tested +5V and +8v voltage regulators.
> Didn't see much in troubleshooting.  Anyone have any ideas where I should look next ???
> 
> 73 Jesse Maher W6JMM


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