Amtronics Velocity Microphone

This is a strange looking microphone created, no doubt, to resemble the classic RCA model 77.  It is a ribbon velocity type and from the materials used in its construction, I would guess that it dates to the 1950's.  Other than the manufacturer and serial number on the name plate, there is no other information on the mike itself, and I know nothing more about it.  The former owner was a ham, so it is quite possible that it was marketed strictly within that market.  

The construction is crude, but interesting.  The aluminum castings used for the bottom section and the top cap are identical to those used by RCA for their model MI-6206 "Aeropressure" mike, except that they lack the cast-in RCA logo.  The center section consists of a piece of perforated sheet steel bent into a cylinder and welded at the seam.  Threaded brass adapters mate this piece to the aluminum castings.  The center section was painted an unfortunate shade of beige, the aluminum parts had a clear coat of lacquer, and the openings were covered by red silk.