RADAR TEST SET
GENERAL INFORMATION - Continued
communication system for air traffic control. Mode S
interrogators provide surveillance of both ATCRBS
equipped and Mode S equipped aircraft. Mode S
transponders will reply to ATCRBS interrogators. Mode S
interrogations can be directed to specific Mode S equipped
aircraft using a unique 24-bit address assigned to each
A condition that exists when a nearby object(s)
causes a portion of the Test Set radiated signal to
be reflected. This condition may cause erroneous
reply indications. To cure this condition, the Test
Set operator should change position (angle or
distance) from the target and repeat the test.
A term used to describe RF over-the-air testing and does not
refer to harmful radiations. Radiated tests are performed by
free-space coupling between the Test Set and
transponder/interrogator antennas. The Test Set operator
aims the unit at the transponder/interrogator antenna when
performing the test.
A term that refers to modes 1, 2, 3/A, and C.
Technically, mode C is not a SIF mode, but is similar
to the modes 1, 2, and 3/A.
An air-to-air interrogation system that provides traffic
advisories to the flight crew (Traffic Alert Collision
VER BIT 1
Mode 4 Verification bits A1 or B1 produce alternate
END OF WORK PACKAGE
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