Paging system operation – Codan Radio MT-4E Analog and P25 Digital - User Guide User Manual
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MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | USER GUIDE
Chapter 3: MT-4E Radio System Confi gurations Page 17
PAGING SYSTEM OPERATION
The MT-4E modules may be confi gured to operate in digital and/or analog paging confi gurations, such
as base station paging, remote paging or simulcast paging using the CI-PM-3 paging modulator. The
CI-PM-3 is confi gured via the front panel switches and internal jumper settings.
The CI-PM-3 paging modulator supports both analog and digital paging formats, and can transmit
POCSAG and other 2-level modulation schemes at transfer rates of 512, 1200 and 2400 baud. It can
also be confi gured for use as a data repeater, whereby 2-level paging data is recovered, re-shaped and
then re-transmitted to an additional repeater/paging transmitter.
The CI-PM-3 supports 4-level modulation formats at data transfer rates up to 6400 bps. Each of the
four modulation deviation levels can be independently set, making the CI-PM-3 suitable for use in such
pager signaling schemes as Motorola’s FLEX™ paging protocol.
The receiver, transmitter and CI-PM-3 paging modulator are shown in Figure 3-5.
Figure 3-5: MT-4E Analog / Digital Paging System shown with one pair of transceivers
The CI-PM-3 uses an on-board frequency reference source consisting of a 10 MHz OCXO with
a frequency stability of +/- 0.35 ppm from -30 C to +60 C. For high stability applications (such as
Simulcast), the CI-PM-3 paging modulator may be confi gured to use an external high stability reference
source (i.e. rubidium, GPS or WWV) with a standard stability greater than or equal to 0.002 ppm, to
discipline the on-board phase-locked loop OCXO oscillator.
The CI-PM-3 has a current draw of less than 250 mA.
SET
DEV
4 LEVEL
SETUP
MODE
DATA
MODE
A
D
2 LEVEL
SET
MOD
NORM
REF IN
REF OUT
PAGING
MODULATOR
DATA
INT
FREQ
REF
EXT
DATA / CTRL
PORT
PULL DOWN
TO REMOVE
TRANSMITTER
CNTL
BUS
MIC
RF OUT
A D
ANALOG
DIGITAL
NORM
OFF
KEY TX
MIC MODE
REF
IN
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
RECEIVER
NORM
SQ. DISABLE
OFF
CNTL
BUS
A D
RF N
I
REF
IN
USB
FREQUENCY (MHz)
MADE IN CANADA
MODEL # CODE
VOL
SYSTEM REGULATOR
METER
+
-
MADE IN CANADA
ON
OFF
SPKR
INT
EXT
EXT
SPKR
OFF
POWER
ON
2
1
5
4
3
6
7
8
11
10
9
FUNCTION
12