K2 VCO Alignment problem

[Robert Greenwalt-2]

Hi

I've worked my way through assembling my k2 and I've reached a problem:
 Everything seems fine until the 4000 kHz, R30 -> 6V alignment of L30.  I
can only reach 5.65V.  I have verified D23-26 are the right part, oriented
correctly.  I have verified D21-22 are the right part and oriented
correctly.  I've counted wires entering the center of T5 (16 and 4).  I have
verified the all the caps in VFO and VFO Range Selection (except C75, which
is missing in my version).

Searching the web I find lots of info about what to do if the voltage
doesn't vary and lots of hints about what to check if the voltage is too
high.  Any suggestions if the left side of R30 varies from 1.87V up to
5.65V?

Oh - and a separate K2 question - my flip-down tilt stand metal piece seems
too wide for the width of the feet: the plastic feet that get bolted to the
base end up 12.7 cm apart but the bent metal piece is about 14 cm wide at
the corresponding part.  I expect some spring, but I'm having trouble
compressing it enough to fit and I wonder if this is normal..

Thanks

Robert (K6RJG)
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[Don Wilhelm-4]

Robert,

Spread or squeeze the turns of T5 and see if the voltage increases by
that means - overshoot the 6 volts a little and do the final adjustment
with L30.  If the problem persists, check the capacitor values in the
VFO Range Select area - see te schematic to identify the capacitors
involved, I do not have the schematics here while on vacation, so I
cannot identiy them for you.

Yes, the tilt bail does need to be compressed when mounting it.  I use a
wood clamp to compress it, but several ther methods can be used - work
safely.  Do not overcompress it to permanently reduce the width or the
bail will be loose after installation.
If you have 2 long  (1 inch) 4-40 screws available, one method that
works is to mount the first foot, and then put the long screws into the
second foot - they will be at an angle, but put nuts on them anyway and
slowly alternate tightening the two screws until they are snug and
straight.  Then remove the long screws one at a time and put in the
normal length screws with the lockwashers.

73,
Don W3FPR

Robert Greenwalt wrote:

> Hi
>
> I've worked my way through assembling my k2 and I've reached a problem:
>  Everything seems fine until the 4000 kHz, R30 -> 6V alignment of L30.  I
> can only reach 5.65V.  I have verified D23-26 are the right part, oriented
> correctly.  I have verified D21-22 are the right part and oriented
> correctly.  I've counted wires entering the center of T5 (16 and 4).  I have
> verified the all the caps in VFO and VFO Range Selection (except C75, which
> is missing in my version).
>
> Searching the web I find lots of info about what to do if the voltage
> doesn't vary and lots of hints about what to check if the voltage is too
> high.  Any suggestions if the left side of R30 varies from 1.87V up to
> 5.65V?
>
> Oh - and a separate K2 question - my flip-down tilt stand metal piece seems
> too wide for the width of the feet: the plastic feet that get bolted to the
> base end up 12.7 cm apart but the bent metal piece is about 14 cm wide at
> the corresponding part.  I expect some spring, but I'm having trouble
> compressing it enough to fit and I wonder if this is normal..
>
> Thanks
>
> Robert (K6RJG)
>  
>

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Please help support this email list: http://www.qsl.net/donate.html