Tyco Mastr III, Руководство по установке

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LBI-38636S
19
Telephone Company Ordering Information
When ordering a telephone line, the following must
be considered:
1. Type of circuit:
Voice grade, 2-wire termination, for radio
control, and tone remote system - send/
receive; voting system - receive only.
2. DC continuity not required
3. Impedance: 600 ohms 20%
4. Line Loss:
Tone remote system:
Sends 2175 Hz tone for 125 milliseconds, and
it must arrive at the base station at no less than
-20 dBm including long-term variation.
Average voice is 10 dB below the 2175 Hz
tone burst.
Voting system:
Sends a continuous 1950 Hz tone when the
receiver is squelched, and it must arrive at the
voting selector at no less than -30 dBm
including the long-term variation.
5. C-1 conditioning if necessary. (If two phone
lines are to be tied in tandem, it is usually proper
to specify C-1 conditioning.)
6. If more than one phone line is to be used, a block
diagram showing locations and type of
equipment to be used should be provided the
telephone company.
TELEPHONE LINE INSTALLATION
DC Remote Installation
Two-Wire Operation
For two-wire operation, connect the pair to TB101-3
and -4. If the remote control unit at the other end is an
RCN 1000, use J3-3 (red) and -4 (green). Refer to
Methods 1 and 2 in Table 1 and associated illustration for
examples (Figures 8 & 9). Jumpers should be placed on
P104-1 to P104-2 and P105-1 to P105-2 on the Interface
Board. Figures 15 & 17 shows the location of Interface
Board connectors and jumpers.
NOTE
Polarity must be maintained, if the
metallic control pair is being used for DC
control.
Four-Wire Operation
For examples, refer to Methods 3 and 4 in Table 1,
and the associated illustrations showing the different
methods (Figures 10 & 11). Jumpers should be installed
on P104-2 to P104-3 and P105-2 to P105-3 on the
Interface Board.
E & M Signaling
E & M lead signaling systems derive their name from
certain historical designations of the signaling leads on
circuit drawings. An "
M " lead is associated with the
trans M it function or M outh, while the " E " lead is
associated with the rec E ive function or E ar. In two-way
radio systems with remote control, E & M Signaling can
be the only type of control offered by the available carrier
circuits.
Generally, both 4-Wire Audio and E & M Signaling
options are used to interface between the radio and carrier
systems. However, 2-Wire Audio can be used in the two-
way radio portion of the control system if hybrids are
installed to provide transition between the 2-Wire and 4-
Wire connections. Usually the E & M Signaling is
separated from the audio (separate line) in both 2-Wire
and 4-Wire installations.
Figure 7 illustrates a typical interface between a two-
way radio system and a multiplex/microwave system. The
Remote Control Console and Base Station are equipped
with the E & M Signaling Option and the 4-Wire Audio
Option. The console provides a regulated -48 Vdc output
(or -24 Vdc with minor modifications) to the "
M " lead
when the TRANSMIT switch is pressed. This -48 Vdc
activates a tone encoder (usually 3825 Hz) in the
multiplex rack. The tone encoder modulates the carrier
frequency, which is transmitted over the microwave link.
At the station end of the microwave link, the signal is
demodulated and the 3825 Hz tone operates a tone
decoder in the multiplex rack. The output of the decoder
results in a contact closure, which a48 Vdc (or
+24 Vdc) to the control shelf. This voltage should be
connected between TB101-1 and TB101-6 on the
Interface board. Jumpers on P104 and P105 of the
Interface Board should also be removed. If +48 Vdc is
being used, resistors R116 and R118 on the Interface
Board should also be removed.
When the system is configured in this manner,
approxi8 milliamperes flows through the DC
control decode circuitry on the backplane. This will cause
the T/R Shelf to decode a +6mA control current to key the
transmitter and route line audio to the transmitter.