Hi Dave,
A good source of an accurate frequency counter is your local hamfests.
I've seen (and bought) HP-5382A frequency counters for $30. If you can
find one with an "Option 1", that has a high stability reference oscillator
in it. Calibrating the 5382A against WWV using the two-generator method
will give you the accuracy you need.
Keep us posted on how you resolve your BFO alignment problem.
73,
ed - k9ew
On Mon, Nov 14, 2011 at 4:02 PM, David and Dianne on Comcast <
dhhdeh@comcast.net> wrote:
> Hi Everyone,
>
> After a 10 year hiatus, my love affair with
> Corsair II has resumed after I recently acquired a
> pristine sample of this transceiver. It came to me
> nearly flawless regarding electronics, mechanics
> (switches and PTO etc.) and cosmetics. This is one
> fine transceiver to use on CW and SSB. My K3 has
> been sitting idle for a while now.
>
> But as received, it was obvious that the BFO
> frequencies were not correct for SSB producing a
> very pinched audio. So I replaced the stock SSB
> filters with INRAD 2.8's with a great improvement
> in SSB fidelity as I had done in my earlier CIIs
> from the mid-1990's
>
> Against my better judgment, I tweaked the trimmers
> on the DSB board tied to the 9.000 MHz crystal and
> of course got things messed up.
>
> The CII manual states that calibration of these
> trimmers (C1, C2 and C3) on the 80980 DSB Board
> requires a frequency counter. This is a piece of
> equipment that I have never owned.
>
> I was able to get SB-N and SB-R spot on by ear by
> zero beating against WWV 10 MHz and using their
> 500 and 600 Hz tones that alternate each minute
> during the hour. (I zero beat WWV in SB-N and SB-R
> against a 500 and 600Hz audio tone generator
> program on my computer). It's easier to do than to
> explain.
>
> Here's the problem. While SB-N, SB-R and my CII
> frequency counter are now spot on against WWV, my
> CW Rx frequency reads 700 Hz low against the CIIs
> frequency counter. I assume that TX frequency is
> also low as I have no trouble getting CW calls to
> respond to me on my frequency.
>
> In SB-N and SB-R it is reading correctly, just not
> so in CW. It's a minor annoyance that I can
> mentally compensate for but I would like to get it
> fixed if I can.
>
> Can anyone recommend a procedure for doing this
> 'by ear' without a frequency counter?
>
> And if in the end I need a counter, can anyone
> recommend one that won't break the bank? I have
> seen many on eBay etc. for relatively modest cost.
> I know that a high quality counter can be expensive.
>
> I have seen several "Leader" Nixie readout
> counters in the used market but know nothing about
> them. I have also seen a mini-counter kit from
> Cumbria Designs in the UK and a Chinese counter,
> the LDB-TFC2700L.
>
> Finally, I fitted Phil's (K4DPK) PTO stabilizer to
> the CII with outstanding results. It makes the PTO
> extremely stable over long periods of time. The
> circuit works as advertised, is an easy install
> and Phil is a great guy to do business with. The
> remote VFO is next.
>
> Thanks any suggestions.
>
> 73 de N1LQ-Dave
>
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