SYSTEM THEORY OF OPERATION

CE-1008

Use of one cable-wrap meter for indicating cable wrap on the antenna reduces cable conductor

requirements, permits mounting the meter on the same panel with the antenna indicators, and simplifies operator

functions.

NOTE

Reference phase current for all synchros must be supplied from a common phase source.

SYSTEM THEORY OF OPERATION

GENERAL (See Figure 1-2) - The Antenna System is installed in an inflatable radome and has azimuth and

elevation rotation capabilities. The Antenna System and associated control units allow an area in space to be searched

for a point or points of UHF or microwave radiation throughout the frequency range of from 1 to 12 GHz.

(1) Operation of the Antenna System is possible in three modes - manual, slave or scan. In either of the

three modes, positioning of the antenna is controlled by two identical channels, an azimuth channel and an elevation

channel, each of which is capable of receiving control voltages from a local or remote source and converting these

voltages into azimuth and elevation positioning data. In addition, the azimuth channel may be controlled by voltages

originating in a scan generator in the Control Indicator. In the manual mode of operation, the antenna is positioned by a

60-cps control voltage generated by handwheel-driven synchros. In the slave mode of operation, the antenna and

counters on the Control Indicator are positioned by a 60-cps control voltage from a remote source. In the scan mode of

operation, the antenna scans a predetermined sector in azimuth in response to control voltages generated by the scan

generator. In this mode, the elevation positioning circuit functions as in the manual mode.

(2) Synchro outputs, which are proportional to the azimuth and elevation angles of the antenna, with respect

to zero-degree azimuth and elevation reference points, are provided by the Antenna System.

(3) The direction of true heading is relative to a furnished reference line and earth stable coordinates. The

azimuth orient controls on the Antenna Position Power Supply allow a compensation factor to be set into the system for

misorientation of a system to the established references.

(4) Figure 1-2 is an overall block diagram of the QRC-280(A) Antenna System which indicates the major

functional components of the Antenna System and the relationship of these components to the control units. The

Antenna Control Power Supply provides operating power, servo excitation, and azimuth

Revised January 22, 1968

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