[Milsurplus] What was TRC-1 used for?

[Robert Nickels]

Somewhere along the line I picked up this cool yagi in a knock-down 
transit case called AS-20F, which according to the label is for the 
TRC-1.   I'm curious what the TRC-1 was used for, the one French website 
that I found seems to lump it in with microwave relay systems, but the 
TRC-1 (which consists of the R-19 receiver made by Hallicrafters and the 
T-14 transmitter) operated on a single frequency in the 70-100 mc 
range.    There is a chart showing how to adjust the length of the yagi 
elements over this range.   I don't have any docs or cables but there 
are two type N connectors for feedlines, so maybe it ran duplex?

I figure someone here can enlighten me a bit!

73, Bob W9RAN