User's Guide

DANIELS
ELECTRONICS LTD
TM
CI-PM-3 Paging Modulator Instruction Manual 1-1
1 GENERAL
1.1 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 configuration, 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 configured 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 configured 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 in non-repeater mode (i.e. in a base station paging transmitter
application only) 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 configuration;
- 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 configuration;
- connection for optional CTCSS encoder / decoder;
- balanced 600 Ω / single-ended microphone input;
- selectable digital delay for Simulcast operation