[Collins] http://en.wikipedia.org/wiki/Rockwell_Collins

[Dr. Gerald N. Johnson]

On Wed, 2007-05-30 at 21:06 -0400, kiyoinc at attglobal.net wrote:
> There's a Collins Radio article on Wikipedia (I mentioned the Signal/One 
> article on the Signal/One list.)
> 
> http://en.wikipedia.org/wiki/Rockwell_Collins
> 
> Check out the Collins article and consider improvements to it.   I 
> thought it was pretty good.
> 
> The article says that 54,000 R-390A's were made.  Seems like a large 
> number and unless many were destroyed, suggests that an R-390A should 
> be, what, $50?

There should be contracts known to the 390A crowd to justify some
production number. Most were not built by Collins and the contractors
often didn't build the PTO or mechanical filters to Collins drawings
which probably saved them paying for Collins patent rights. And many
were destroyed.
> 
> Rod Blocksome reports 26,000 KWM-2 and 2A.  While many were abandoned 
> and destroyed in Vietnam, this seems like a large number too.

Could be but Rod has closer chances at finding official records than
most of us. S lines went past the first ground of 100,000 randomized
serial number labels.
> 
> I'm not sure where I'm going with this but production should have some 
> bearing on collector valuation.
> 
> As I own 75S-1 serial number 55, I'm sensitive to this issue.

For those of us with radios made a year or two after that one, we can't
hang age on serial number because Art decreed that the serial numbers
would be issued in random order. He neglected to stop model changes and
MCN numbers being sequential to say nothing of company style (winged to
meatball) changes during a model's lifetime. I don't know how many were
made before the random serial numbers though. I did check out the
component specification for the serial number tags sometime probably in
1963 and it sure did say "random order."

This randomness came from the 75A4 where even dealers in new ones varied
the price according to the serial number, the bit later ones having
upgrades in circuitry considered quite beneficial to their operation.
Art didn't appreciate that.

A serial number 55 radio probably was not standard production but an
engineering prototype. Collins practice was to reserve the first 100
serial numbers for engineering models and prototypes and to begin
production with sn 101. And it might one assembled by a Collins employee
from parts purchased from the engineering parts crib and the surplus
store with that relatively unusual serial number. Long about the
beginning of 1964 a new policy prohibited selling the PTO as a spare
part so if the home project needed one it had to be by buying a 312
external PTO. That seemed to slow the building of S-line from parts
around Cedar Rapids.

One would need a log of prototype serial numbers to be sure what your
radio is.
> 
> de ah6gi/4

-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer