[ARC5] ARC-5 with Upper and Lower Sideband switch?

[D C Macdonald]

Thinking further on the matter, I believe I would
probably move the BFO to at least 3, maybe as
much as 5 kHz to each side of the IF center freq.
A BC-454 or equivalent would require proportionally
less offset due to its inherently tighter selectivity.
Basically the bandwidth remains a percentage of
the IF frequency when strictly LC circuitry is used
in the IF stages if Q remains comparable.

Many years ago (late 1950s) I used the 1.5-3.0
receiver as the IF for a Morrow 5BR-1 converter
as my primary station receiver.  It was a big plus
when compared to either my S-20R or S-40A.
I still had that 1.5-3.0 when the tornado hit in
May of 1999.

73  ---  Mac, K2GKK/5


----Original Message Follows----
From: "Tom Bridgers" <Tarheel6 at msn.com>
To: "D C Macdonald" <k2gkk at hotmail.com>
Subject: Re: [ARC5] ARC-5 with Upper and Lower Sideband switch?
Date: Tue, 8 Jun 2004 22:34:05 -0400

Thanks, DC...  I'm thinking of doing this myself, and your reply is very
helpful.
thanks again,
-tom

----- Original Message -----
From: "D C Macdonald" <k2gkk at hotmail.com>
To: <Tarheel6 at msn.com>; <arc5 at mailman.qth.net>
Sent: Tuesday, June 08, 2004 8:41 PM
Subject: RE: [ARC5] ARC-5 with Upper and Lower Sideband switch?

 > I'd say it would be pretty simple.  Position the BFO off
 > center from the IF (say 1.5 kHz) then switch in (or out)
 > a small capacitance that would put the BFO 1.5 kHz to
 > the other side of IF center frequency.
 >
 > As broad as the IF of a BC-455 is, I'd say that unwanted
 > sideband rejection would be pretty poor, but it would
 > be noticeable.
 >
 >
 > ----Original Message Follows----
 > From: "Tom Bridgers" <Tarheel6 at msn.com>
 > To: <arc5 at mailman.qth.net>
 > Subject: [ARC5] ARC-5 with Upper and Lower Sideband switch?
 > Date: Tue, 8 Jun 2004 19:15:45 -0400
 >
 > There's a BC-455 over on the Bay side (# 5702924629) that claims to have
 > upper or lower sideband selectable with a switch.  I've seen this done
 > primarily with crystals on either side of the IF freq., but how would you
 > accomplish switch selectable upper or lower sideband on an ARC-5 if you
 > didn't use crystals?  (My assumption is the one on the Bay doesn't use
 > crystals...)
 > Thanks in advance for your thoughts,
 > -tom