[Collins] R-388 and CE Sideband Slicers for improved SSB reception

[Park, Ted]

Team

This is not strictly speaking a "plug in" solution as some assembly and =
minor modification is required :-) but I have retuned two Central =
Electronics  "SIDEBAND SLICER" models..the Model A and the improved =
Model B (with added Q Multiplier and variable null and peak tuning) to =
work with my R-388. The operator's manual shows how these can be hooked =
up to a 75A-2 but there is/was nothing I could find describing how to =
use them with an R-388. Basically I retuned the SIDEBAND SLICER for a =
500 KHz if frequency and adapted the 75A-2 minor circuit modification =
information from the description in the Central Electronics operating =
manual. These use a "phasing" method of exalted carrier demodulation as =
originally described in QST for April 1948, page 19, June 1948 page 11 =
and July 1948 page11.

These are no longer manufactured and were a "niche" product offered in =
the early-50s during the major communications paradigm transition from =
AM equipment to SSB equipment so that receivers designed primarily for =
AM could be used more effectively for SSB reception. These still show up =
periodically and fairly often on E-Bay. I was able to get  my A model =
for $75 on E-Bay a few years ago and I paid  $125 (plus shipping costs) =
a year ago for my B model because it was just like new, had *all* the =
options and updates and documentation and was a 10 out of 10 =
cosmetically and functionally. Expect to recap any of these that you get =
unless someone else has already gone through them.  I am using the B =
model now with my R-388 and I am using the A model with my Hallicrafters =
SX-71 (after retuning the model A IF back to  455 KHz from 500 KHz).

Perhaps others have had similar experiences. Overall I am *very* pleased =
with the operation of the old Central Electronics "SIDEBAND SLICER"s and =
I like the fact that they use tubes and are of the same era as the R-388 =
and 75A-2... (my Model B documentation is dated January 1 through =
October 12, 1953).=20

I recommend that if you get one get the "B" model and also get the =
additional outboard model AP-1 IF option if possible. The A model will =
provide the SSB improvement but I *really* like the additional features =
the B model provides for working CW with the R-388....(variable IF =
tuning and selectivity with the Q multiplier)............or listening to =
AM with carriers present (the null filter is pretty effective to take =
out unwanted carriers).=20

73, Ted, K6XN

ps The knobs on the Sideband Slicers and the paint color are very =
similar (identical?) to that of the Collins 75A-2.

pps These also work great with a Hammarlund SP-600.

ppps These are pretty easy to recap and the documentation is sufficient =
to do a competent job without "guessing".

-----Original Message-----
From: collins-bounces at mailman.qth.net =
[mailto:collins-bounces at mailman.qth.net]On Behalf Of Phil LaMarche
Sent: Friday, October 15, 2004 8:41 AM
To: collins at mailman.qth.net
Subject: [Collins] R-388


Hey Guys,

Does anyone have a plug in product detector for the R-388 that I could
purchase?

Phil

Philip LaMarche
LaMarche Enterprises, Inc.
www.instantgourmetspices.com=20
727-944-3226
(800) 395-7795 pin 02
Cell 727-510-5038
N.A.S.F.T # 30210
W9DVM
=20
=20
=20
=20

--=20
Outgoing mail is certified Virus Free.
Checked by AVG Anti-Virus (http://www.grisoft.com).
Version: 7.0.280 / Virus Database: 264.11.1 - Release Date: 10/15/2004
=20

______________________________________________________________
Collins mailing list
Home: http://mailman.qth.net/mailman/listinfo/collins
Help: http://mailman.qth.net/mmfaq.html
Post: mailto:Collins at mailman.qth.net