[Hallicrafters] RE: I Need SSB Mod for Hallicrafters S-40A

[Ian Webb]

Well, compared to a PTO based receiver of the era, the drift even with a
damp
chaser on an SX-101 was reduced but still annoying.  No matter that the
critical stages were constantly heated by filaments as well.

I know from using one for a couple of years at W9BGX, Northwestern
University,
in the 1959 and 1960 school years.  Not too bad on 20 meters but not
much fun in
my experience on 10 and 15.

Ian, K6SDE


rbethman wrote:

> The drifting could well be reduced with the solution used in the SX-101s.
> The "damp Chaser".  It not only reduced the "supposed" moisture, but
> provided a constantly heated VFO/BFO that made drift insignificant.
>
> Bob - N0DGN
> ----- Original Message -----
> From: "Ian Webb" <ianwebb5 at attbi.com>
> To: <hallicrafters at mailman.qth.net>
> Sent: Tuesday, December 03, 2002 9:30 PM
> Subject: Re: [Hallicrafters] Fw: I Need SSB Mod for Hallicrafters S-40A
>
> > I pointed out to the poster in a private e-mail, unless you're doing
> > this for the "fun of it" you're not going to create a receiver that is
> > much fun to use on SSB.  I know from experience when the S-40B was still
> > a popular receiver during the transition from AM to SSB that other than
> > 40 meters and lower in frequency the drift is intolerable for
> > comfortable SSB reception.
> >
> > I personally wouldn't bother doing anything but receiving SSB with the
> > RF way down and the BFO on and AVC off.  The tuning rate and drift
> > combine to make it a full time job to try to follow a SSB signal.  With
> > CW the problem is the same but there at least you don't get a garbled
> > voice just a CW note that is changing pitch constantly.
> >
> > Ian, K6SDE
> >
> >
> > Glen Zook wrote:
> >
> > > There were some modifications that would work with the
> > > S-40A in the first couple of editions of the ARRL SSB
> > > manual.
> > >
> > > Frankly, it is probably easier to "tap off" of the 455
> > > KHz i.f. and build a separate circuit that includes a
> > > good filter.  The S-40A is "way" to wide for decent
> > > SSB operation.
> > >
> > > Of course, you can use the old turn off the AVC, run
> > > the audio gain wide open, and use the r.f. gain as the
> > > volume control.  That does work fairly well.
> > >
> > > Glen, K9STH
> > >
> > > --- Andrisin <andrisin at verizon.net> wrote:
> > >
> > > I am looking for a SSB mod for the Hallicrafters
> > > S-40A,eg product detector mod. Can anyone provide a
> > > copy of this mod or refer me to a website that has
> > > such a mod?
> > >
> > > =====
> > > Glen, K9STH