TM 11-5805-424-15/NAVELEX 0967-220-9010/TO 31W2-2G-41
indicate which end of the shield
(5) Connect the corrected timing signal from
should be grounded. Do not ground
terminals 4, 5, and 6 of terminal board TB2 to
the digital data receive equipment.
the shield at both ends of the line.
Each individual ground bus must be
connected
to
the
centralized
Note. If security equipment is used
grounding point through separate
ground leads.
timing signal from terminals 7, 8, and
9 on terminal board TB2 to the
security receive equipment.
(a) Remote.
1. Connect the common shield ground
(6) If the station clock signal is generated by
at terminal 10 of terminal board TB2
another equipment, connect the station clock
to the centralized grounding point.
signal to terminals 7, 8, and 9 of terminal board
2. Connect the common signal ground
TB1.
at terminal 11 of terminal board
TB2, through a separate wire, to the
Note.
The external clock signal
centralized grounding point.
return line should be returned to a
3. Connect the case (ac) ground at
signal ground at the signal source
terminal 5 of terminal board TB4,
end. If it is not, connect the return
through a separate wire, to the
line (terminal 8 of TB1) to the signal
centralized grounding point.
ground at terminal 11 of terminal
(b) Local.
If all the shield grounding
board TB2 of the MD674(P)/G.
(including those recommended for remote
grounding) and signal grounding is to be
made at the MD-674(P)/G, connect a
(7) If external alarm indicators are required,
ground lead between terminal 10 of
connect the alarm output from terminals 13
terminal board TB2 and terminal 5 of
through 18 of terminal board TB1 to the alarm
terminal board TB4 and a separate
indicators.
ground lead between terminal 11 of
(8) If an external order-wire control (in place of
terminal board TB2 and terminal 5 of
TALK REQUEST pushbutton) is to be used,
terminal board TB4.
connect the circuit to terminals 18, 19, and 20 of
c.
Multiplex Terminal Connection.
terminal board TB2.
(9) If an external order-wire control indicator is to be
(1)
Connect one of the MD-674(P)/G's as indicated
used, connect the output from terminals 3, 4,
in b(1) through (13) above.
and 5 of terminal board TB3 to the order-wire
(2)
Connect the remaining MD-674(P)/G's as
control indicator.
indicated in b(1) through (10) and (13) above.
(10) To disable the digital data receive equipment
(3)
Connect parallel connections between terminals
when the carrier signal (vf receive) fails,
12, 13, and 14 of terminal board TB2 on each
connect terminal 20 of terminal board TB1, and
MD-674(P)/ G.
terminals 1 and 2 of terminal board TB3, to the
(4)
Connect parallel connections between terminals
disable (inhibit) circuit of the digital data receive
15, 16, and 17 of terminal board TB2 on each
equipment.
MD-674(P)/G.
(11) Connect the vf output (send side) from terminals
(5)
Operate the INPUT and OUTPUT impedance
12, 13, and 14 of terminal board TB2.
switches (fig. 2-3) on one of the MD-674(P)/G's
(12) Connect the vf input (receive side) to terminals
to 600Ω.
15, 16, and 17 of terminal board TB2.
(6)
Operate the INPUT and OUTPUT impedance
(13) Connect the ground leads to a centralized
switches on the remaining MD674(P)/G's to
grounding point as follows:
50KΩ.
d.
Single-Channel Repeater Connection.
Note. Normally, shield grounds are
(1)
Connect the 115- or 230-volt ac power to
connected at the signal driving end
terminals 3, 4, and 5 of terminal board TB4 on
of the connecting wires.
The
both MD-674(P)/G's.
designations LOCAL SHLD ORD and
REMOTE SHLD GRD, at each
individual input and output line,
Change 5
2-6
