Nope. I recall looking at it when I owned one, and
being sad that it couldn't be converted to a
superhet--so it stands out in my mind. The band is
first down converted to 5-5.5MHz, and then the PTO
output is used to drive a second mixer. Opposite of
"traditional" superhet method.
Today, though, you could use a KK7B R2 (or similar)
setup, at the 5-5.5MHz IF. That would work pretty
good.
Shawn KB1CKT
--- jones_winston@bellsouth.net wrote:
> >
> I sold my Century 22 not long ago, so I don't have a
> manual for reference. However, I recall the Century
> 22 was often called a "double direct conversion"
> rig. It has a PTO which tunes the same range of
> frequencies for all bands (can't remember the freq.
> range). The PTO signal is then mixed with a crystal
> oscillator, with various crystal frequencies, to
> bring it up (or down?) to the operating frequency,
> as
> required by a direct conversion receiver. The signal
> tunes on both sides of zero beat, like other direct
> conversion receivers.
>
> So, by hooking the freq. counter up to output of the
> crystal conversion mixer, going to the detector, the
>
> counter would read the correct frequency, without
> any offsets, as required by superhet receivers.
>
> The Triton IV is a superhet, so you have to program
> in the IF offset to the counter so it will read the
> correct operating frequency. This is not needed in a
> direct conversion receiver like the Century 22.
>
> 73, Winston K4CWQ
>
>
>
> > From: "Harry N. Coates" <WA8HC@charter.net>
> > Date: 2006/09/07 Thu AM 11:21:28 EDT
> > To: <tentec@contesting.com>
> > Subject: [TenTec] Century 22 Question
> >
> > Don,
> >
> > I've never owned a Century 22, but, I think TT
> used the same PTO mixer scheme in most of thier
> radios..
> >
> > You can probably tap off the PTO.. But, the PTO
> output is probably 5.0-5.5 Mhz not the final freq..
> You
> will have to adjust for the LO
> > freq used at the mixer to display the true final
> > output.. I did this for my Triton IV..
> >
> > GL,
> >
> > Harry
> >
> >
> > Harry N. Coates
> > Comstock Park, MI
> > WA8HC@charter.net
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> >
> http://lists.contesting.com/mailman/listinfo/tentec
> >
>
> _______________________________________________
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> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
Shawn Upton, KB1CKT
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