Connections for Operation in FADAC Systern (TT-537/G)

TM 11-5815-206-12 /TO 31W4-2PGC1-61

2-14. Connections for Operation in FADAC Sys-

metallic path between two stations; the earth is

tern (TT-537/G)

used as the return path to complete the circuit.

Establish a ground-return signal circuit as foIlows

at each station:

Turn off all equipment. Insert the telephone-type

a. Establish a good ground connection point as

plug at the end of the line cable (fig. 1-6) into the

mating connector on the front panel (fig. 3-1.1

)described in Paragraph 2-7b (2).

or behind the hole in the left Side of he-TT.

b. Connect an insulated wire from the ground

connection point to one of the two line terminal

537/G dust cover (fig. 1-8). Connect the 55-pin

board terminals that are associated with the signal

connector of the line cable to the mating connector

circuit.

o f the computer. If the telephone-type plug is

c. Connect the signal line to the other terminal

damaged, connect the signal lines directly to line

associated with the signal circuit.

terminals 3 () and 4 (+).

2-17. Line Current Adjustment (TT-4(*)/TG

2-15. Connections for Full-Duplex Operation

and TT-335/TG)

a. High Level Units (B, fig. 2-8).

For circuit line-up purposes, one of the stations

(1) Loosen the nuts of terminals 1 through 6

( n o r m a l l y the station of highest authority) is

of the line terminal board (B, fig. 2-6) and move

designated the control station and the others are

both shorting bars on the line terminal board to

designated noncontrol stations. Be sure the LINE

the vertical position (lower end of bars not in

INCREASE knob (fig. 3-1) is fully counter-

contact with any lower terminal).

clockwise at the control station and fully clock-

(2) Connect one of the two receive signal lines to

wise at all noncontrol stations before beginning the

terminal 3; connect the other signal line to ter-

l i n e current adjustment procedure during in-

minal 4. If the pointer of the D.C. MILLIAM-

stallation of the teletypewriter.

PERES meter (A, fig. 3-1) does not move to the

a. Half-Duplex Operation (De System) (A, fig.

right, reverse the connections to terminals 3 and 4.

2-7).

(3) Connect either of the send signal lines to

(1) The operator at the control station must

terminal 1; connect the other signal line to ter-

slowly turn the LINE INCREASE knob clockwise

minal 2.

u n t i l the pointer of the D.C. MILLIAMPERES

( 4 ) Connect the two leads of Power Cable

meter (fig. 3-1) indicates 75 on the meter scale.

Assembly CX-1202/1U (fig. 1-5) to terminals 5 and

(2) If only one station is connected to the

6. Connect the plug on the other end of the CX-

control station teletypewriter, the operator at the

1202/U to a 105-125-volt, dc power source.

n o n c o n t r o l station must slowly turn the LINE

NOTE

INCREASE knob counterclockwise until the

When connected for full-duplex operation

pointer of his meter indicates 60 on the meter

( (1) through (4) above), each station

scale. If more than one noncontrol station is in the

normally provides power only for the signal

circuit, the operator at each noncontrol station, in

circuit connected to its SEND terminals

turn, must turn his LINE INCREASE knob

(send circuit). T o p r o v i d e p o w e r a t a

c o u n t e r c l o c k w i s e slowly to decrease the meter

station for the receive circuit also, connect

reading in equal amounts until the meter indicates

one of the receive signal lines to terminal 6

60 (for example, in a three-station circuit, each of

(instead of terminal 3 ((2) above) connect a

the two noncontrol stations would decrease the

jumper from terminal 3 to terminal 5, and

current reading approximately 7 ma).

m a k e all other connections exactly as

b. Half-Duplex

Operation

(Voice-Frequency

described in ((1) through (4) above. See

System ) (B, fig. 2-7). Turn the LINE INCREASE

caution, paragraph 2-11 b.

knob clockwise slowly until the pointer indicates 20

b. Low Level Units (TT-698(*)/TG ) (C, fig. 2-

milliamperes on the meter scale,

8).

c. Full-Duplex Operation (B, fig. 2-8). Turn the

(1) Connect the two send signal lines to the

LINE INCREASE knob clockwise slowly until the

XMIT OUT terminals of A1TB1.

pointer indicates 60 milliamperes on the meter

(2) Connect the two receive signal lines to the

scale.

RCVR IN terminals of A1TB1,

NOTE

(3) Connect signal lines ground shields to the

When a TT-4(*)/TG is installed for full-

GRD terminal of A1TB1.

duplex operation (B, fig. 2-8), the LINE

2-16. Connections for Ground-Return Signal

I N C R E A S E knob is used to adjust the

Circuit

value of current in the receive circuit only

A ground-return signal circuit includes only one

Change 1

2-11