Codan Radio Communications VT-3H040-S-HSO User Manual

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Paging Modulator Instruction Manual
IM55-CIPM3
1
Introduction
The CI-PM-3 Paging Modulator module is an 
optional plug-in component of the MT-3 Radio 
Repeater System. This module provides digital 
and/or analog paging capability for Daniels MT-3 
transmitters in all supported frequency bands.
The CI-PM-3 is designed for low power 
consumption, typically drawing less than 250 mA 
in steady state. In its standard confi guration, the 
CI-PM-3 uses an on-board frequency reference 
source consisting of a 10 MHz OCXO with a 
standard stability of 0.03 PPM. 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. To ensure that paging signals are the 
same relative to each transmitter, the CI-PM-3 
also incorporates a limited delay compensation 
for the different link propagation paths between 
transmitters.
The CI-PM-3 Paging Modulator supports both 
analog and digital paging formats, and can 
transmit POCSAG and other 2-level modulation 
schemes at data 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 1600 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.
Setup conditions are established via front panel 
switch settings, while internal jumper settings 
and setup adjustments are easily accessible 
using the EC-96, 96 Pin Extender Card.
The CI-PM-3 Paging Modulator includes the 
following standard features:
 
• low power analog and CMOS control  
 circuitry.
• extended operating temperature range;
• jumper selectable Repeater/paging  
 transmitter confi guration;
• on-board +/-0.03 PPM 10 MHz OCXO;
• front panel selection of PLL OCXO using  
  external high stability frequency reference;
• jumper and line selectable analog/digital               
 paging confi guration;
• connection for optional CTCSS encoder/ 
 decoder;
• balanced 600 
Ω/single-ended microphone  
 input;
• selectable digital delay for Simulcast  
 operation
GENERAL 
INFORMATION