Some Test Mast Information

from TM 9-1400-250-10/2 starting page 48
27 (U). Radar Test Set Group
The radar test set group (fig. 29) consists of the radar test set (2, fig. 29), the RF detector (3, fig. 29), and the antenna assembly-mast group (1, fig. 29).
The radar test set group is used to aline and test the target tracking, target ranging, and missile tracking radar systems. The target track and missile track antenna reflectors are alined optically by sighting and alining the axis of the antenna reflector with a point on the graduated arms at the top of the antenna assemhly-mast group (l, fig. 29).
The target range antenna reflector is alined and corrected for parallax by radiating rf energy from the target range antenna-receiver-transmitter group to a feedhorn at the top of the antenna assembly-mast group.
The rf energy received from the feedhorn is converted to a dc voltage by the RF detector (3, fig. 29) to produce an indication of the alinement of the antenna reflector. The radar test set (2, fig. 29) generates rf test signals that are radiated from the feedhorn at the top of the antenna assembly-mast group.
These signals simulate missile transmitted signals or target return signals and are used in checks and adjustments of the missile and target tracking radar systems.

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