This postcard was in pictures at my parent's place in Indiana. It was sent to my Gumpy, Keith D Jones, on 8 July 1957. I don't know who sent it, but I'm glad they did (and that it was kept all these years). It looks like the postcard was sent to Gumpy's work address, at the US Naval Avionics Facility, Department 225, at 21st & Arlington Streets in Indianapolis, Indiana.
information on the Naval Avionics Facility [pdf link] in Indianapolis. Apparently the US Government commissioned the plant in May 1942 to produce a top secret bombsight.
The facility was located at 6000 East 21st Street, Indianapolis. The Naval Avionics Center, Indianapolis (NACI) was closed with the Base Realignment and Closure (BRAC) process. It was featured in the December 1968 issue of Naval Aviation News (available online at http://www.history.navy.mil/nan/backissues/1960s/1968/dec68.pdf).