GB> Misc Crystals
bcarling at CFL.RR.COM
Thu Oct 13 15:34:37 EDT 2005
Well if anyone out there really IS brave enough or has the time to
build converters for their Q5ers these days, I have a great supply
of converter crystals (while they last) - with many new listings at:
73 & thanks for looking - Bry, AF4K
On 13 Oct 2005 at 8:22, n2ey at aol.com wrote:
> The BC-453/converter idea is one that somehow never got the ink it deserved.It appeared in
> QST several times, starting as early as 1948and as late as 1966. It also appeared in CQ about
> 1956, in an article by W6SAI IIRC.
> I wonder sometimes if there was some sort of bias against that setup, because it cost less than
> most beginner receivers and outperformed both homebrew and manufactured receivers costing
> much more. With the slugs in the '453 pulled up and a decent alignment, the bandwidth is about
> 1.5 kc at 3 dB down, and there's a pronounced single-signal effect. Almost too sharp for SSB,
> and you copy AM by the one-sideband-and-carrier method. It's not as sharp as I like for CW but
> it's a heck of a lot better than any other simple CW rx of the time.
> I struggled with simple regens, a BC-454, Heath AR-2, and even an SX-99 for a total of about
> four years as a hamuntil I came upon that idea, which blew them all right out of the water. Of
> course the idea really only works well up to about 10 Mc because of images, although there was
> at least one article about a 20 meter converter for the '453 that used two RF stages and double-
> tuned coupling between stages to keep the images under control.
> Back in the bad old days, one could obtain a good Q5er for five to fifteen dollars, the crystals for
> less than a dollar apiece, and the rest of the parts for ten to twenty dollars - or nothing, if you
> could find some old BC sets for parts.
> The first incarnation of the idea that I built used the chassis and tuning cap of an old AA5 rx, with
> the cap from another AA5 added. Tubes were 12BA6 RF, 12BE6 mixer and 12AV6 oscillator, all
> from the AA5s too. Power supply was from an old TV set, which was way overkill but the price
> was right. Coils were wound on pill bottles, RF chokes were TV peaking coils and the only parts
> actually bought were the xtals. Other xtals permitted listening to other bands, like 49 meter
> SWBC. If you use 365 uuf variables without the trimmers and carefully adjust the turns on the
> coils, one coil can cover 160 through 40 meters. It's no trick at all to cover 3 to 8 Mc. if you're not
> interested in 160.
> If you come across a BC-453 for cheap, it's a really neat project.
> 73 de Jim, N2EY
> -----Original Message-----
> From: bcarling at cfl.rr.com
> To: glowbugs at piobaire.mines.uidaho.edu
> Sent: Wed, 12 Oct 2005 18:50:09 -0400
> Subject: Re: GB> Misc Crystals
> On 12 Oct 2005 at 14:20, n2ey at aol.com wrote:
> > If you have a BC-453 (Q5er) and put a crystal-controlled converter in front of
> it, it makes a really decent receiver for 80, 40 and possibly 30 and 20 meters.
> > Q5er tunes 190-550 kc, so a 7550 xtal is perfect for 40 meters if you want
> 7000 to be at the 550 end of the dial. A 6750 xtal will put 7000 at 250 on the
> > and 7300 at 550 on the dial.
> BUT it seems like VERY few people are building HF converters
> these days.
> I have had those same crystals on offer for a couple of years and
> no takers.
This list is a public service of the City of Tempe, Arizona
Subscription control - http://www.tempe.gov/lists/control.asp?list=BOATANCHORS
To post - BOATANCHORS at LISTSERV.TEMPE.GOV
Archives - http://listserv.tempe.gov/archives/BOATANCHORS.html
More information about the Boatanchors