[Collins] Winged versus Round Emblems

[Gerald]

On Mon, 2005-07-04 at 13:06 -0400, ERogerWms at aol.com wrote:
> Hello: My only Collins radio is my cherished winged 51S-1, but I am 
> considering a 75S-3C. I am confused by the relationship ship between the various emblems 
> (ie, winged, small round, large round, Rockwell, etc) and age. My 
> understanding is that winged units are older than round units, and, of course 75S-3Bs 
> are older than 3Cs.

Nope.

> Yet, there are winged 3Cs and round 3Bs. Were 3Bs and 
> 3Cs manufactured simultaneously for several years? 

All their production life, 3Bs and 3Cs were manufactured together. There
may have been a period very near the end of production that only 3C were
made.

> 
> I would appreciate any information on this matter, ie age and emblems. Please 
> feel free to reply off-net directly to me.
> 
> Thanks, Roger KB4THL

These models were made together:
KWM-2 and KWM-2A
75S-1 and 75S-2
75S-3 and 75S-3A
75S-3B and 75S-3C
32S-1 and 32S-2
32S-3 and 32S-3A

In every case the difference was that the second model in each line had
the optional second crystal board kit installed, generally at the
factory. Otherwise there is NO circuit difference between radios made at
the same time. Radios in each line above were made together at the same
time for the total same time period. The left column was NEVER earlier
than the right column.

You also can't go by serial numbers as Art was annoyed that various
versions of the 75A4 sold (even new) for different prices so he decreed
that the S-Line serial numbers had to be issued in random order. I've
read the component specification for the serial number tags and it
definitely called for the serial numbers to be in random order. At least
when I read it in 1963 or 1964.

Long about 1964, Collins Radio stylists came up with the new image,
scrapping the winged emblem and going to the round emblem and terra
cotta colored trim for everything. Which thoroughly destroyed Art's wish
for age to not be a factor in sales (new or used) prices.

Radios made in the late Collins round emblem and Rockwell era sold for a
great deal more than the late winged emblem radios and save for the
emblem and minor circuit changes (covered in service bulletins that are
available) were identical in circuits and performance.

The only ways to tell age within a model pair is by date codes on
original parts such as crystals, electrolytic capacitors and tubes plus
any MCN tags or stamps. Though the change of emblems from winged to
round to Rockwell round do set date ranges for the S-3B/C. Serial
numbers don't help. Even then those purchased parts can have a spread of
a few months to a year depending on when they were purchased in
anticipation of production and all are replaceable and interchangeable
from various vintages.  If one is very lucky, the dates on crystals,
tubes, and electrolytics will have a narrow distribution setting the
earliest date the receiver might have been made. If the electrolytics
are original, they are in need of being replaced before they fail
catastrophically filling the radio with shredded foil and crepe paper
filled with conductive electrolyte.

Back in the spring of 1964 while TDY at Richardson, my boss Lloyd Winter
caught me in the lab drooling over a 51S-1. His advice (and he'd been in
charge of the 51S-1 and 75S developments) was that the 75S-3B/C was a
superior receiver and with a crystal pack would cover the same range as
the 51S-1.
-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer