[ARC5] T-44-B Microphone? OBG-1?

[Don Merz]

What's a T-44-B microphone? It has a bizarre PL-179 connector on the end and the cord includes a JK-26 jack presumably for headphones. 
And while I have yinz (that's Pittsburghese--widely spoken in the new home of the Stanley Cup) on the line....
where was the OBG-1 Sonar Echo Ranging Equipment used? This thing says Type CFF-43058 Driver-Receiver with a contract date of 8-44. Made by Freed. The power was apparently supplied by internal batteries!
73 Don Merz, N3RHT
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/arc5/attachments/20160614/73da8ddf/attachment.html>