from TM 9-1400-250-10/2 - page 47

25 (U). LOPAR Antenna-Receiver-Transmitter Group
Note. The key numbers shown in parentheses in a through f below refer to figure 27.
a. General. The LOPAR antenna-receiver-transmitter group (fig. 27) consists of the antenna and the receiving and transmitting equipment for the low power acquisition radar (LOPAR) system. The group consists of the acquisition antenna (2), acquisition antenna pedestal (5), acquisition receiver-transmitter (3), the acquisition modulator (4), and an auxiliary antenna (1). The pedestal, receiver-transmitter, and modulator are cylindrical tubs stacked one on the other. The auxiliary antenna is mounted on the acquisition antenna. The entire group is supported by a tripod secured to the pedestal at the top and to leveling jacks at the bottom.
b. Acquisition Antenna. The acquisition antenna (2) is mounted on the acquisition antenna pedestal (5) and rotates continuously in azimuth during operation. The elevation scan of the antenna reflector is variable within the range from 0 to - 391 mils. A protective Fiberglas radome encloses the antenna reflector. Selective identification feature /identification friend or foe (SIF/IFF) equipment is attached to a holding bar mounted on the lower portion of the antenna.
c. Acquisition Antenna Pedestal. The acquisition antenna pedestal (5) supports the acquisition antenna (2). The pedestal contains the antenna drive equipment and the equipment that electrically couples the antenna, the acquisition receiver-transmitter (3), and the acquisition modulator (4).
d. Acquisition Receiver-Transmitter. The acquisition receiver-transmitter (3) contains receiving and transmitting equipment associated with the LOPAR system. Built-in test equipment is incorporated in the acquisition receiver-transmitter to facilitate maintenance.
e. Acquisition Modulator. The acquisition modulator (4) contains the high voltage and pulse generating equipment for the transmitting system of the LOPAR system.
f. Auxiliary Antenna. The auxiliary antenna (1) is mounted on top of the main acquisition antenna and rotates in synchronism with it.