2nd Bn, 56th Arty, 1966-68 (Source: Richard Tracy) The exterior of the AN/MSQ-18 Operations Central: the van's large air conditioning unit -- for the "comfort" of the electronics, not the operators! -- is apparent, as are the two panels on the side of the van, where a multitude of incoming/outgoing ADL/voice transmission lines were connected; you can also see the cables carrying radar video from the AN/GSS-1 Electronic Search Central (to the left) directly into the OC van. [Also a good shot of the structure of the BOC radar tower.]