I have a 580 Delta. It is definitely double conversion just as Walt states.
Carl Moreschi N4PY
cjm@qvssoftware.com
----- Original Message -----
From: "Steve Ellington" <N4LQ@iglou.com>
To: <WA4VEC@aol.com>; <tentec@contesting.com>
Sent: Tuesday, May 02, 2000 9:11 PM
Subject: Re: [TenTec] Re: 580 Delta-was Receiver Lineage
>
> Better look again. I believe the first beating occurs within the vfo to
> produce the correct oscillator frequency for each band. The Triton and
Omni
> series worked the same way, the only difference being the 9mc vs 6.3mc IF.
>
> Note I am anti Hertz when it comes to cycles!
>
> Steve
> N4LQ
> ----- Original Message -----
> From: <WA4VEC@aol.com>
> To: <tentec@contesting.com>
> Sent: Tuesday, May 02, 2000 7:11 PM
> Subject: [TenTec] Re: 580 Delta-was Receiver Lineage
>
>
> >
> > In a message dated 00-05-01 22:51:52 EDT, N4NT wrote:
> >
> > <<
> > Well, I was apparently mistaken about the 580 Delta's IF scheme. I had
> > thought it the same as the Corsairs -- knew it took different filters
> from
> > the older Omni's, but was designed to work the WARC bands without the
18
> MHz
> > spur.
> >
> > I may be mistaken about this, too, but thought the rebuild kits for the
> > PTO's of the 580 Delta and the Corsairs were the same. Thought the
> Tritons,
> > older Omni's and Argosies were alike.
> > >>
> >
> >
> > I just looked at the manual for the Delta and technically it actually is
> > double conversion. It mixes the input signal with output from a band
> crystal
> > to generate an 11.0 - 11.5 Mhz signal which is then beat against the PTO
> > which goes from 5.2 to 4.7 Mhz to get the 6.3 Mhz final IF.
> >
> > You are correct in that the rebuild kits for the PTOs are the same since
> they
> > all use the same set of parts that come in the kit. The drive rod for
the
> > Delta is left threaded so that the frequency varies in the opposite
> direction
> > from the one in the Omni's. This is due to the 'upside down' mixing
> scheme.
> > Remember some of the old rigs where you tuned the dial one way on say 80
> and
> > in the other direction on say 20? This was due to the economy of using
a
> > single band crystal for both bands and adding it in one case while
> > subtracting in the other.
> >
> > I agree that the other you mentioned are pretty much alike. I did not
> like
> > the inaccuray of the digital readout when I had my first Delta, but
these
> > days it doe not seem to matter for some reason.
> >
> > Walt
--
FAQ on WWW: http://www.contesting.com/tentecfaq.htm
Submissions: tentec@contesting.com
Administrative requests: tentec-REQUEST@contesting.com
Problems: owner-tentec@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|