From: jwl@sedist.cray.com (Jim Lynch)
Subject: Re: Info on Collins models wanted.
Organization: Cray Research, Inc.
Date: 31 Jul 92 09:55:10 CDT

In article <110@microm.UUCP>, brad@microm.UUCP (Bradley W. Fisher) writes:
|> I'm interested in learning more about the Collins line of ham gear.
|> Can anyone point me to (or summarize here) some documentation on 
|> the various models and their features. I keep hearing of references
|> to "s-line" , or "KWM-2A" and such but really have no idea as to the 
|> type or vintage of these rigs. Did Collins survive until the digital
|> age?

I am not an expert on Collins gear, but I've been the proud owner of a fair amount of it, so I'll take a shot.  The earliest Collins equpiment that I remember was the 32v? and 75a? where the ? is a single digit in the range of 1-4.  I don't remember a 32v4, but there might have been one.  These were built in the early 50's (and probably in the 40's too).  The 32v3 (for instance) was an am and cw transmitter.  It was a real work horse.  The 75a4 was the last of the "a" series receivers.  It was one of the b


est for its time.  I think  the first ssb transmitter that Collins marketed in the 50's (if not the first, one of the first) was the kws-1.  It was a kilowatt ssb transmitter.  It was primarily a companion to the 75a4.  In about '58 Collins designed the s-line series of transmitters/receivers starting with the 75s-1 and the 32s-1.  These rigs were designed as ssb/cw radios.  They used mechanical filters to provide the best (for the time) bandpass filters available.  Compared to the older Collins gear these


 were lightweight, compact and efficient radios.  They were amateur band only, but by replacing the (plug-in) crystals in the radios you could cover almost the entire 3-30 megacycle band (no hz in those days 8^).  Another feature that I think was a first, was that they could be interconnected so that they would transceive.  The transmitter was controlled by the receiver's pto (vfo, in generic terms).  That way you didn't have to "zero beat" your transmitter to your receive frequency before transmitting.  T


he 32s-1 had a pair of 6146 tubes in the final and would put out about 100 watts.

In later years Collins updated the s-line series to include a 75s-3 and 32s-3.  The 75s-3 seemed to be more popular.  I guess they must not have made as many improvements.  I just remember a lot of people running a 75s-3 and 32s-1 together. 

The kwm-2 was a design that was a marriage of the s-line equipment.  It was built in the same style of the s-line.  The cabinet was just a bit larger (deeper) than the s-line units. (The 32s-1 and 75s-1 shared the same cabinet design.  Their skins were interchangable)  It was a true transceiver as we know them today.  Like the 32-s1, it had a pair of 6146's and ran about 100 watts output.  It was generally promoted as a mobile radio and there was a mobile power supply that bolted to the back of the radio. 


 These were all tube radios and needed 800 and 300 volts, in addition to the 12 volts from the car to run.

The kwm-1 was a predecessor to the kwm-2 and, maybe, the s-line.  It was a 20-15-10 meter band mobile rig.  I don't remember much about them, except that they were not as popular as the "m-2", as the kwm-2 was generally known.

The 30s-1 and 30l-1 were two linear amplifiers in the s-line family.  The 30s-1 was a real brute and could put out well over the legal limit.  It had a floor mounted cabinet that contained the power supply.  The amp itself usually sat on top of it.  The 30l-1 was a smaller linear that used a pair of 811(A) tubes.  It was rated at something less than a kw, but I don't remember the exact specs.  It was a desktop unit that looked a lot like the 32s-1.  It may have had the same skins, but my memory is hazy.  I


t was a lightweight, but rugged (not physically, but electrically) linear.  In later years, I have heard of people putting 572b tubes in the L-1 and getting a solid kw (input).

The first solid-state radio that Collins put out was the KWM-380 (at least that was generally used by hams).  I believe that this came out in the mid-70's.  The price tag was about $3500 at the time, and it was generally believed that the radio was not as good as the kwm-2a.  I think it was improved over the years, but due to that preception and the high price tag, Collins never had the success with the kwm-380 that they did with their s-line and m-2 lines.  About that time, I think Collins was having trou


bles and seemed to abandon the amateur market.  Rockwell bought them out sometime after the introduction of the kwm-380 and it seemed like they gave up on amateur radio.  These are just my perceptions, I had moved from Iowa by then and lost my contacts in Cedar Rapids.

Another less popular member of the s-line family was the 51s-1.  This was a general coverage receiver.  It looked a lot like the 75s-1, but was a little different interally.

Also available were accessories such as the 312b-1 (right number?) console 
that had a watt meter (forward and reflected power), speaker and phone patch.  The 612s-1 (I know that isn't the right number) transverter that was used to work 6 and 2 meters.  There were some others, but I don't remember them..  I think there was an external vfo for the kwm-2, but I haven't seen one for years.  With that the kwm-2 had most of the functionality of the the separate s-line twins.

I understand that the kwm-380 is still available at a very high price.  I heard $30,000.  And that you have to have one built, they don't stock them.  All of this could be rumor, however.

That is what I remember.  Please don't flame me for a lousy memory!
|> 
|> BTW, I have only been a ham for about 3 months now (General class),
|>
 and operate with a Heathkit SB-102.
|> 
|> -- 
|> -= Brad Fisher =-  (PPSEL)               I'm just    | Micro Maintenance, Inc.
|> usenet: brad@microm.tnet.com                 a       | 2465 W. 12th St. #6
|>  -or-  ...!asuvax!telesys!microm!brad    wanna be    | Tempe, Arizona  85281
|> packet: n7xss@kc7y.az.usa.na            UNIX guru !  | 602/894-5526

-- 
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Jim Lynch, Sales Analyst,  Cray Research, Inc. / ARS: K4GVO
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