BFO test frequency out of range

[Craig Marscin]

Hi everyone!

I have been building SN 4078, and all has gone smoothly so far.  The
radio is finished and works (except for the problem below) as do the SSB
and DSP options.  I have been chasing one problem for a while however.  
When I did the BFO test the BFO Low Freq came in as 4911.23 which is
ok.  The high freq was only 4915.77, a bit short from the 4916.3 it is
supposed to be.  I have replaced C173 and C174 with diffrent caps (same
value), confermed L33 is working properly and isn't shorted to
anything.  I even removed it from its spot (kept it hooked up) and it
didn't make a sizeable change.  The voltages at U11 pin six was 5.89 and
pin seven was 5.3 which are within tolerance.  The DC voltages
everywhere else seem reasonable.  The AC voltages anywhere I could
measure seemed reasonable.  One intresting thing to note is the BFO
chrystals seem to be the wrong frequency.  They are labled ECS V
4.9136-S Korea G3.  This is diffrent then what the instruction manual
states they should be labled.  The remaining chrystals on the board,
except the VFO, are ECS V 4.9136 -S Korea J3.  A little diffrent labling
but same frequency.  I have confirmed the rest of the chrystals on the
board are correct.  I could be totally off track with the chrystal
idea...  Can anyone confirm it or give me ideas as to what I might have
done wrong?

I love this radio, but when I transmit on the upper sideband it doesn't
suppress the carrier at all (lower sideband is fine).  I believe this
problem is the result of the problem above since I couldn't set the USB
filters correctly.

Thanks
Craig
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[Craig Marscin]

Hi All,

I finally was able to get this problem corrected!  A couple emails back
and fourth with Elecraft's parts department and they were able to
conferm that I was shipped the wrong BFO crystals.  Apparently, a very
small number of K2s around my serial number 4078 had this same
affliction.  A quick swap and I was finally able to meet the max and min
for the BFO test.  As a result now when I transmit on the USB the
carrier is properly filtered out.  It has also really helped the audio
quality now that I am able to do CAL FIL properly.

Thanks to everyone that helped!   Especially Gary KI4GGX and Jim W4ATK.

73, Craig KC9GUS
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