[ARC5] Stromberg-Carlson Model D Aircraft Receiver (RFL, ARC, BRC)

[Mike Morrow]

Michael wrote:

>The original path was: Designed by RFL, built by S-C, then installed
>and maintained by A.R.C..   The Model B was an RFL design as was the
>initial work on the Model D.  With the transfer of engineering staff
>from RFL to A.R.C., which was a done deal by 1934, the design effort
>moved placing the entire effort in A.R.C.'s lap.

It would be interesting to see a chronology and outline of the relationships between Radio Frequency Laboratories, Aircraft Radio Corporation, and Boonton Radio Corporation, all located in Boonton, NJ.

I have an RFL Type B-3 aircraft range receiver, serial 218.  I don't know when it was made, but I'd guess in the mid-1930s.  I also have a Boonton Radio Corp. Type 185 aircraft range receiver, serial 33, made for the USN [NOa(s) 2876], of WWII vintage.  Size, parts, and construction style of the Type 185 are vaguely similar to the earlier RFL unit.

The RFL Type B-3 utilizes a brass seal (pin) to prevent outer case removal without breaking seal.  A plate around this seal says:

             WARNING
   DO NOT BREAK THIS SEAL UNDER
          ANY CONDITION
IF FAILURE SHOULD OCCUR WIRE TYPE AND
SERIAL NUMBER IMMEDIATELY TO THE MAN-
UFACTURERS AND RETURN THE UNIT TO THEM
AS SOON AS POSSIBLE.  A NEW UNIT WILL BE
SHIPPED PREPAID ON RECEIPT OF WIRE
UNDER CONDITIONS OF GUARANTEE.

RFL's unit must have been considered a pretty high-tech, state-of-the-art unit.  I guess they didn't want anyone messing with the hardware except them, even for simple tube replacement.  That sounds like old telephone company policy!  I wonder how long such requirements were issued or observed.

>The Type K was completely an A.R.C. project with
>RFL uninvolved with the design at all.

I've seen picures of the Type K receivers that Mike Hanz uncovered, and the system diagram on Mike's website.  It would be interesting if any components of the Type K transmitter system still survive anywhere.

Mike / KK5F