Well you can see by the nameplate that it is part of AN/FGC-6, whatever that was. Google doesn't seem to be any help. So I guess we need a military comms expert to identify it. --- "Ya can argue all ya wanna, but it's dif'rent than it was." "No it ain't! No it ain't! But ya gotta know the territory." Meredith Willson, The Music Man