[TenTec] Corsair II Double Side Band Board (BFO) Problem

[David and Dianne on Comcast]

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