Section Ill TECHNICAL PRINCIPLES OF OPERATION

TM 11-6625-2975-12

Section Ill TECHNICAL PRINCIPLES OF OPERATION

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Subject

Para

GeneraI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Test Set Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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1-12. GENERAL.

The test set is a microprocessor-controlled signal generator that produces audio-modulated rf sig-

nals. Modulated rf signals simulate VOR, Iocalizer, glideslope, and marker beacon ground station

signals. Simulated ground station signals are used to test and troubleshoot VOR, Iocalizer,

glideslope, and marker beacon receivers. Front panel mounted keys allow an operator to select

ground signal to be simulated. Selection of desired rf (carrier) frequency places signal generator in

correct mode of operation and preset condition for mode of operation.

VOR, Iocalizer, glideslope, or marker beacon receivers under test are connected to RF OUT connec-

tor on test set front panel. Simulated ground station signal produced by test set is applied through RF

OUT connector to receiver under test.

1-13. TEST SET OPERATION.

INITIAL POWER-ON/MEMORY CHECK

During initial power on, test set automatically checks Its memory for any incorrect outputs. Displays,

keys, and indicators will go dark for a short time until check Is complete, Results of the check areas

follows:

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