Specifications

4. Check CEC/IMC Switch Audio connections.
• This refers to audio connections between the
CEC/IMC Switch and the CNI GETC or
Repeater. Refer to CEC/IMC manual
LBI-38662.
If the problem is isolated to the CNI GETC, refer to the
GETC Maintenance Manual LBI-38894 for detailed board
level test procedures.
CNI INTERFACE REQUIREMENTS
Refer to Figure 15 for the required connections between
the CNI and a repeater, when using a repeater other than
EGE’s MASTR II (IIe) or MASTR III stations.
The CNI GETC requires the following voltages and
signals:
POWER (J10-1)
(Ground, J10-2)
+13.8 Vdc, 2A
VOL\SQ HI (J7-2)
(Vol/Sq LO, J7-1)
Unfiltered receiver audio,
including Voice and Channel
Guard tone.
Once in the GETC, this signal is
routed to the Low Speed Data
Filter where it is checked for the
presence of a Channel Guard
tone.
Typically, the repeater is set up
for a 1 V rms output when an
“on channel” RF signal
modulated with a 1000 Hz tone
at 3 kHz deviation is applied.
Carrier Activated SQ.
(RUS IN) (J7-14)
Input line should be set high (5
Vdc) when the receiver is
unsquelched by an “on channel”
carrier.
The line is low when the receiver
is squelched.
E & M Signalling
voltage or Secur-it tone
hold detect
(Remote PTT IN, J7-9)
A ground (active low) needs to
be applied to the GETC when
the repeater decodes a 2175 Hz
tone or E & M contact closure is
used.
This signal (low) alerts the
GETC to the presence of a call
from a remote source
(CEC/IMC) for the duration of
the low condition.
The CNI GETC provides the following output signals:
Channel Guard tone
(J19-5)
GETC outputs a 3 Vpp, EIA
RS-220A Channel Guard tone
(67 Hz to 192.8 Hz) to the
repeater.
Signal is sent for transmission
with voice as an indicator of
valid channel activity or to pass
on priority scan information.
Delay PTT (J6-1) This line is pulled low (4 mA
O/C output) when the GETC
wants to key the repeater’s
transmitter for any reason.
REPEAT/REMOTE
REM PTT OUT (J6-16)
Output is High (5 Vdc) for
Repeat Audio.
Output is Low (0 Vdc) for
Remote Audio.
CEC/IMC Switch levels:
Remote Audio Level
(In & Out)
0 dBm, 0 Vdc offset
Impedance 600 ohms
E & M Signalling
voltage or 2175 Hz tone
-20 dBm
LBI-38986
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