Types of Operation - TM-11-5895-217-120026

Control

Function

Microphone switch ---------

Normally, a two-position switch. In one position, energizes the transmission cir-

cuits; in the other, deenergizes the transmission circuits.

Light control - - - - - - - - - - - - -

Varies the brilliance of the panel lamps on the control unit.

19. Types of Operation

a. The transponder set is operated re-

(2) P l a c e the master control in the

motely from the aircraft cockpit through

STBY position. The pilot light

the use of the control unit. Depending on

should light.

the settings of the various controls, the

Note: If the pilot light does not light,

press the test button. If the pilot light still

transponder set can be operated to reply

fails to light, either the light is burned out

to interrogation signals with normal, sif,

or power is not reaching the transponder

or civil pulse codes; to provide identifi-

set.

c a t i o n - p o s i t i o n reply codes; to transmit

(3) Adjust the pilot light to the desired

automatically, emergency reply codes; and

brilliance by opening or closing

to provide personal identification (MODE

the lens shutter.

(4) Allow the transponder set to warm

2) or flight leader identification (MODE

up from 3 to 5 minutes.

3).

(5) F o l l o w the procedures in para-

b. T O operate the equipment for any par-

ticular type of operation, perform the fol-

graphs 22 through 27 for the de-

l o w i n g procedures:

sired type of operation.

(1) `Starting procedure (para 20).

Note: The control unit is provided with

illumination from the rear of the front panel.

(2) Procedure for desired type of op-

This light and the pilot light, are not go-

eration (para 22 through 27).

no-go indicators of the receiver-transmitter

but only indicate that power is reaching

(3) Stopping procedure (para 28).

the equipment.

20. Starting Procedure

21. Reply CodI ng By Assigned

(fig. 6)

CodeNumber

Caution: Be careful when rotating the

s e c o n d digit selectors on MODE 1 and

For tactical purposes, IFF code assign-

MODE 3 controls to their extreme clock-

ments are continuously being changed. The

wise and counterclockwise positions. Use

c o d e s consist of two- or four-digit num-

o f excessive force can cause damage to

bers which indicate the correct settings of

the switching mechanism.

c o d e controls or switches. The trans-

a. Preliminary. Set the various controls

ponder set converts this code to a coded

as follows:

pulse train. For modes 1 and 3, the as-

signed code numbers are two-digit num-

Control

Position

b e r s which are n o r m a l l y set up by the

p i l o t with visual control indicators. For

Master control -------------

OFF.

AUDIO switch --------------

OFF.

m o d e 2, the assigned code number is a

I/P switch -----------------

OFF.

four-digit number which is preset b e f o r e

MODE 2 switch -------------------

OFF.

MODE 3 switch --------------------

f l i g h t . This is n o r m a l l y done by the or-

OFF.

MODE 1 code control -------

To read 00.

ganizational repairman or crew chief.

MODE 3 code control -------

To read 00.

NORMAL.

Function control ----------------

Master power on-off switch --

Off.

22. Normal Operation

AN/APX-44 circuit breaker--

Off.

(fig. 6 )

b. Starting.

Note: When the function control is set in the NOR-

MAL position, all preset code combinations will be

(1) Place the master power on-off con-

disabled on all modes and a standardized reply will

t r o l to on and energize the AN/

be automatically transmitted by the transponder set

A P X - 4 4 circuit breaker.

when interrogated.