Rockwell ROA 117 2247*1 Specifications

LBI-39149
Maintenance Manual

EDACS COMPACT
VERTICAL VOTER
TABLE OF CONTENTS
SYSTEM INSTALLATION AND SERVICE................ LBI-39153
DIGITAL VOTER SHELF............................................. LBI-39150
DIGITAL RECEIVER & SELECTOR........................... LBI-39151
ROCKWELL MODEM & RS-232 INTFC CARD ........ LBI-39152
INTERFACE PANEL..................................................... LBI-39075
VOTER CROSS-CONNECT INTFC............................. LBI-39142
ANALOG VOTER ......................................................... LBI-38676
REDUNDANT POWER SUPPLY SYSTEM ................ LBI-39038
POWER DISTRIBUTION PANEL................................ LBI-39158
AC OUTLET STRIP ...................................................... LBI-4841
CABINET FAN ASSEMBLY ........................................ LBI-4842
ericssonz
LBI-39149
NOTICE!
This manual covers Ericsson and General Electric products manufactured and sold by Ericsson Inc.
NOTICE!
Repairs to this equipment should be made only by an authorized service technician or facility designated by the supplier. Any
repairs, alterations or substitution of recommended parts made by the user to this equipment not approved by the
manufacturer could void the user's authority to operate the equipment in addition to the manufacturer's warranty.
NOTICE!
The software contained in this device is copyrighted by Ericsson Inc. Unpublished rights are reserved under the copyright
laws of the United States.
This manual is published by Ericsson Inc., without any warranty. Improvements and changes to this manual necessitated by
typographical errors, inaccuracies of current information, or improvements to programs and/or equipment, may be made by
Ericsson Inc., at any time and without notice. Such changes will be incorporated into new editions of this manual. No part
of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including
photocopying and recording, for any purpose, without the express written permission of Ericsson Inc.
EDACS and MASTR are registered trademarks of Ericsson Inc.
Copyright February 1996, Ericsson, Inc.
2
LBI-39149
TABLE OF CONTENTS
Section/Paragraph
Page
TABLE OF CONTENTS................................................................................................................................ 3
LIST OF ILLUSTRATIONS ......................................................................................................................... 4
IMPORTANT SAFETY INFORMATION................................................................................................... 5
VOTER SPECIFICATIONS.......................................................................................................................... 6
INTRODUCTION........................................................................................................................................... 7
DESCRIPTION ............................................................................................................................................... 7
VOTER SYSTEM ..................................................................................................................................... 7
SIMULCAST SYSTEM ............................................................................................................................ 8
Control Point....................................................................................................................................... 8
RF Sites............................................................................................................................................... 8
CONSOLE OPERATION.......................................................................................................................... 8
VOTER EQUIPMENT ................................................................................................................................... 9
POWER DISTRIBUTION PANELS......................................................................................................... 9
POWER SUPPLIES .................................................................................................................................. 9
VOTER UNIT ........................................................................................................................................... 10
Digital Voter Shelf.............................................................................................................................. 12
Analog Voter Shelf ............................................................................................................................. 13
EDACS Interface Panel ...................................................................................................................... 14
CONTROLS AND INDICATORS ................................................................................................................ 15
DIGITAL VOTER SHELF........................................................................................................................ 15
Selector ............................................................................................................................................... 15
Digital Receiver .................................................................................................................................. 16
Rockwell Modem Interface Card ........................................................................................................ 17
ANALOG VOTER SHELF ....................................................................................................................... 18
Analog Receiver ................................................................................................................................. 18
Audio Module..................................................................................................................................... 19
GETC INDICATORS................................................................................................................................ 20
Main (Control) Site GETC ................................................................................................................. 20
Satellite Site GETC............................................................................................................................. 20
SYSTEM OPERATION ................................................................................................................................. 21
VOTER SYSTEM ..................................................................................................................................... 21
Analog Voting..................................................................................................................................... 21
Digital Voting ..................................................................................................................................... 21
Dispatch Console Interface ................................................................................................................. 23
SIMULCAST SYSTEM ............................................................................................................................ 23
Control Point....................................................................................................................................... 23
Transmit Sites ..................................................................................................................................... 24
Satellite Receiver Site ......................................................................................................................... 24
Voted Digital Interconnect (Simulcast)............................................................................................... 26
EDACS (NON-SIMULCAST) VOTER SYSTEM.................................................................................... 28
Main Site............................................................................................................................................. 28
Satellite Site ........................................................................................................................................ 30
Voted Digital Interconnect (Non-Simulcast) ...................................................................................... 31
RELATED PUBLICATIONS ........................................................................................................................ 33
GLOSSARY..................................................................................................................................................... 34
3
LBI-39149
LIST OF ILLUSTRATIONS
Figure
Title
Page
Figure 1 - Typical Voter System (non-Simulcast) .............................................................................................7
Figure 2 - Typical Simulcast System .................................................................................................................8
Figure 3 - Console with CEC/IMC in Multisite Network ..................................................................................9
Figure 4 - Typical Power Distribution Panel (24 Volt model shown) ...............................................................9
Figure 5 - Typical +5/±12 Volt Redundant Power Supply System....................................................................10
Figure 6 - Typical 83-Inch Cabinet with Power Supplies..................................................................................11
Figure 7 - Digital Voter Shelf............................................................................................................................12
Figure 8 - Analog Voter Shelf ...........................................................................................................................13
Figure 9 - Typical CV2 Interface Panel Configured for Simulcast Two (2) Channels per Shelf .......................14
Figure 10 - Typical CV2 Interface Panel Configured for Simulcast One (1) Channel per Shelf........................14
Figure 11 - CV2 Selector....................................................................................................................................15
Figure 12 - CV2 Digital Receiver ......................................................................................................................16
Figure 13 - CV2 Rockwell Modem Interface Card ............................................................................................17
Figure 14 - Analog Voter Receiver ...................................................................................................................18
Figure 15 - Audio Module.................................................................................................................................19
Figure 16 - Simplified Voter Block Diagram ....................................................................................................22
Figure 17 - Simplified CEC/IMC To Voter Block Diagram .............................................................................23
Figure 18 - Simplified Voter Signal Flow (Simulcast System) Diagram ...........................................................25
Figure 19 - Typical Satellite Receiver Site Block Diagram...............................................................................26
Figure 20 - Simplified Voter Signal Flow (Simulcast System with Digital Dispatch & VDI) Diagram ............27
Figure 21 - Main-Site Equipment (Single Channel) ..........................................................................................28
Figure 22 - Simplified Voter Signal Flow (EDACS Non-Simulcast System) Diagram .....................................29
Figure 23 - Typical Main Site (Non-Simulcast ) Voted Digital Interconnect Block Diagram...........................31
Figure 24 - Simplified Voter Signal Flow (EDACS Non-Simulcast System With VDI Option) Diagram ........32
Table 1 - Selector Indicators .............................................................................................................................15
Table 2 - Selector Controls and Connectors ......................................................................................................15
Table 3 - Digital Receiver Indicators ................................................................................................................16
Table 4 - Digital Receiver Controls and Connectors .........................................................................................16
Table 5 - Rockwell Modem Interface Card Indicators ......................................................................................17
Table 6 - Analog Receiver Indicators and Controls ..........................................................................................18
Table 7 - Audio Module Indicators and Controls..............................................................................................19
Table 8 - Main (Control) Site GETC Indicators................................................................................................20
Table 9 - Satellite Receiver & Simulcast TX Site GETC Indicators .................................................................20
4
IMPORTANT SAFETY INFORMATION
LBI-39149
IMPORTANT SAFETY
INFORMATION
result in a risk of fire and electric shock. If an extension
cord must be used, ensure:
The following general safety precautions must be
observed during all phases of operation, service, and repair
of this product. Failure to comply with these precautions or
with specific warnings elsewhere in this manual violates
safety standards of design, manufacture, and intended use of
the product. Ericsson, Inc. assumes no liability for the
customer's failure to comply with these standards.
a. The pins on the plug of the extension cord are the
same number, size, and shape as those of the plug
on the power supply.
1.
2.
3.
4.
SAVE THIS MANUAL - It contains important safety
and operating instructions.
Before using this equipment, please follow and adhere
to all warnings, safety and operating instructions located
on the product and in the manual.
DO NOT expose equipment to rain, snow or other type
of moisture.
Care should be taken so objects do not fall or liquids do
not spill into the equipment.
5.
DO NOT expose equipment to extreme temperatures.
6.
DO NOT use auxiliary equipment not recommended or
sold by Ericsson, Inc. To do so may result in a risk of
fire, electric shock or injury to persons.
7
GROUND THE EQUIPMENT-To minimize shock
hazard, the equipment cabinet(s) must be connected to a
good earth or building ground which eventually goes to
earth.
The equipment supplied is equipped with threeconductor AC power cords. These power cords must be
plugged into approved three-contact electrical outlets
with the grounding wires firmly connected to an
electrical ground (safety ground) at the power outlet.
The power cords must also meet International
Electrotechnical Commission (IEC) safety standards.
8.
To reduce risk of damage to electrical cords, pull by
plug rather than cord when disconnecting a unit.
9.
Make sure all power cords are located so they will not
be stepped on, tripped over or otherwise subjected to
damage or stress.
b. The extension cord is properly wired, in good
condition, and
c. The wire size is large enough for the AC ampere
rating of unit.
11. DO NOT operate equipment with damaged power
cords or plugs - replace them immediately.
12. DO NOT operate this product in an explosive
atmosphere unless it has been specifically certified for
such operation.
13. To reduce risk of electric shock, unplug unit from outlet
before attempting any maintenance or cleaning.
14. Use only fuses of the correct type, voltage rating and
current rating as specified in the parts list. Failure to do
so can result in fire hazard.
15. GROUNDING AND AC POWER CORD
CONNECTION - To reduce risk of electrical shock
use only a properly grounded outlet. The system
components are equipped with electric cords having an
equipment grounding conductor and a grounding plug.
Be sure all outlets are properly installed and grounded
in accordance with all local codes and ordinances.
16. DANGER - Never alter the AC cord or plug. Plug into
an outlet properly wired by a qualified electrician.
Improper connection or loss of ground connection can
result in risk of an electrical shock.
17 ELECTROSTATIC DISCHARGE SENSITIVE
COMPONENTS - This station contains CMOS and
other circuit components which may be damaged by
electrostatic discharge. Proper precaution must be
taken when handling circuit modules. As a minimum,
grounded wrist straps should be used at all times when
handling circuit modules.
10. An extension cord should not be used unless absolutely
necessary. Use of an improper extension cord could
5
LBI-39149
VOTER SPECIFICATIONS
VOTER SPECIFICATIONS
(Refer to individual equipment manuals for complete specifications and LBI-39153 for rack-up configuration.)
DIGITAL VOTER SHELF
Size: (Height x Width x Depth)
13.3 cm (5.22 in.) x 48.26 cm (19.00 in.) x 24.03 cm (0.5 in.)
Power Requirements:
+ 5 Vdc @ up to 12.5 Amps (max.)
+12 Vdc @ up to 800 mA (max.)
-12 Vdc @ up to 630 mA (max.)
Weight:
12 kg (26.5 lbs.) maximum
ANALOG VOTER SHELF
Size: (Height x Width x Depth)
17.78 cm (7 in.) x 48.26 cm (19.00 in.) x 24.13 cm (9.5 in.)
Power Requirements:
24 Vdc ±5% @ up to 600 mA (typ.)
Weight:
30 kg (46.3 lbs.) maximum
POWER SUPPLY
Size:
(Height, Width)
(Depth)
Power Requirements:
13.34 cm (5.25 in.), 48.26 cm (19.00 in.)
350A1441P1 - 47 cm (18.5 in.),
350A1441P2 - 41.3 cm (16.25 in.)
110 - 120/220-230 Vac 50/60 Hz @ 6.0/3.0 Amps (max.).
Weight:
11 kg (24.3 lbs.) maximum
POWER DISTRIBUTION PANEL
Size:
(Height x Width x Depth)
Weight:
8.9 cm (3.5 in.) x 48.26 cm (19.00 in.) x 7 cm (2.75 in.)
3.1 kg (6.83 lbs.) maximum
ENVIRONMENT
Humidity (EIA):
90% at 50°C (122°F) non-condensing
Temperature:
Operating:
Storage:
0° C to 40° C (32° F to 104° F)
-20° C to 85° C (-4° F to 185° F)
Altitude:
Operating:
Storage:
up to 4,570 m (15,000 ft.)
to 15,250 m (50,000 ft.)
83-inch DEEP CABINET (Empty)
Size:
(Height x Width x Depth)
Power Requirements:
211 cm (83.06 in.) x 58.42 cm (23.0 in.) x 58.42 cm (23.0 in.)
110 - 120/220 - 230 Vac 50/60 Hz @ 0.5 Amps (max.).
Weight:
approximately 56.7 kg (125 lbs.)
69-inch OPEN RACK (Empty)
Size:
Height
Base (Width x Depth)
Power Requirements:
217.17 cm (85.5 in.)
52.07 cm (20.5 in.) x 32.0 cm (12.6 in.)
110 - 120/220 - 230 Vac 50/60 Hz @ 0.5 Amps (max.).
Weight:
approximately 34.0 kg (75 lbs.)
6
INTRODUCTION
INTRODUCTION

This manual provides an overview of the EDACS
(Enhanced Digital Access Communication System) Compact
Vertical Voter. Additional information for the installation,
setup, and repair of the voter system and individual voter
subassemblies may be found in the maintenance manuals
listed on the front page.
The Compact Vertical Voter (CV2) system is an integral
part of a Voted or Simulcast radio system.
Although functionally equivalent to the older horizontal
voter, the CV2 system’s modular design (a three to one size
reduction) conserves valuable floor space and increases
system reliability.
DESCRIPTION
Voting is a technique for balancing the talk-back range
of portable radios with the talk-out range of high power
transmitters.
Typically, base stations use 100-watt
transmitters that can broadcast their signals much further
than 3 to 5-watt portables. By adding a number of
geographically dispersed satellite receiver sites to the
communication system, the portable radio user can be
confident that if he hears the dispatcher, the dispatcher will
hear him.
The satellite receivers receive audio and digital signals
transmitted by the portables and route the signals to the
centrally located Voter system. The Voter monitors the
SATELLITE
RX SITE
LBI-39149
signals from all receivers including the main site’s receiver
and selects the receiver with the best signals. This process is
referred to as voting. After voting on the best signal, the
Voter routes the voted signals to the main site (Control Point
for Simulcast systems) or to the Dispatcher (see Console
operation). This process ensures that the best signal is
always re-transmitted and/or routed to the dispatcher.
VOTER SYSTEM
A typical (Non-Simulcast) Voter system, as shown in
Figure 1, includes a main transmit/receive site, a number of
receive-only satellite sites, and a centrally located Voter.
The Main Site and Satellite Site receivers receive audio
or digital signals from the portable radios. These received
signals are then sent to the Voter for processing via direct
connection, telephone lines, or microwave links.
At the Voter, the Digital and Analog Voters select (vote
on) the best analog and digital signals. Analog voting
evaluates and selects the site receiving the best Clear Voice
audio transmission. Digital voting selects the site receiving
the best digital signal. Digital signals include Digital Voice,
Data, and Digital messaging (Control Channel signaling).
The Voter continuously compares the analog and digital
signals, selects the receivers with the best signals, and relays
voted digital messages to the main site GETC. It also
directs the Analog Voter to relay voted audio to the main
site and when available to a dispatch Console.
MAIN SITE
SATELLITE
RX SITE
GETC Shelf
Aux RCVR
Shelf
Voted Data
Receiver
GETC Shelf
Control Ch.
Monitor
Transmitter
GETC Shelf
Rec’d Data
Control Ch.
Monitor
Rec’d Audio
Voted Audio
Rec’d Audio
Aux RCVR
Shelf
VOTER
Rec’d Data
Rec’d Data
Rec’d Audio
Figure 1 - Typical Voter System (non-Simulcast)
7
LBI-39149
DESCRIPTION
SIMULCAST SYSTEM
RF Sites
The most common use of the Voter is as part of a
Simulcast system. Simulcast is an EDACS system that
simultaneously broadcasts the same information across a
wide area using a single set of frequencies.
Simulcast systems also include of two or more RF sites.
An RF site may be either a transmit site or a receive only
(Satellite Receiver) site. A transmit site includes both a
transmitter and receiver for each channel as well as common
equipment required for simulcast operation. Receive-only
sites include a receiver for each channel. These sites
enhance portable talk-back coverage. The RF sites are
connected to the Control Point by microwave or fiber optic
links.
A typical Simulcast system, as shown in Figure 2,
consists of:
•
Control Point Equipment
•
Transmit Site Equipment
•
Receive-only Equipment
CONSOLE OPERATION
Consoles allow dispatchers to communicate with field
radios and vice versa. In a Voted or Simulcast system,
multiple consoles may be connected to the system via the
CEC/IMC switch. The switch interfaces with the Voter
through a Voter Digital Relay Board (VDRB) which is
controlled by the CEC/IMC switch or CV2 Selector.
Control Point
The Control Point coordinates the activities of the RF
sites and employs special circuitry for precise control of the
amplitude and phase of each signal. It also routes digital
messages to the Site Controller, Master Alarm system, and
the Console Electronics Controller (CEC) or Integrated
Multisite and Console Controller (IMC) when using Digital
Dispatch.
The VDRB, by default, routes voted audio to the
Control/Main Site and console. When directed, the VDRB
also routes clear voice, data, digitized voice or encrypted
voice calls to and from the CEC/IMC. From the IMC (see
Figure 3), this traffic can be routed to or from other systems
(Multisite) and/or to or from console (dispatch) positions.
The Voter is co-located at the Control Point. It
processes the received audio and digital signals and passes
the best signals on to the Control Point equipment.
SATELLITE
RX SITE
Aux RCVR
Shelf
GETC Shelf
Control Ch.
Monitor
TRANSMIT
SITE
TRANSMIT
SITE
GETC Shelf
GETC Shelf
Rec’d Data
Rec’d Data
Receiver
Receiver
Rec’d Audio
Rec’d Audio
Transmitter
Transmitter
Simulcast
Equipment
Simulcast
Equipment
Control Point
GETC
Voted Data
Rec’d Audio
Rec’d Data
VOTER
Simulcast
Equipment
Voted Audio
Rec’d Audio
Rec’d Data
Figure 2 - Typical Simulcast System
8
VOTER EQUIPMENT
•
Scat Site
CNI Site
Simulcast Site
LBI-39149
Voter Unit(s) (quantity depends on configuration)
In installations using multiple cabinet configurations, up
to three (3) cabinets or racks may be grouped together for
power distribution. The Power Distribution Panels in the
first cabinet in each group distribute the 5, 12, and 24 Volt
power to the other cabinets or racks in the group. The
source of this power may be either external or from the
power supplies installed in the first cabinet.
POWER DISTRIBUTION PANELS
Dispatch Console
CEC/IMC
Jessica
Figure 3 - Console with CEC/IMC in Multisite Network
VOTER EQUIPMENT
The equipment requirements for a CV2 system depends
on the overall system configuration. There are a number of
factors which affect the configuration. These factors include
the number of sites supported, the number of channels, if the
system is Simulcast or non-simulcast, if the system uses
Digital Dispatch or is supporting Voted Digital Interconnect.
Specific configuration details may be found in LBI-39153.
Typically, a CV2 system is installed in either 83-inch
high cabinet or an 86-inch high open rack. The number of
cabinets or racks required to house the equipment depends
on the number of sites and whether the site supplies AC or
DC voltage as the primary power source.
The components installed in a CV2 system cabinet(s) (or
racks) include the following equipment (refer to the example
of an 83-inch cabinet shown in Figure 6):
•
•
•
•
5/12 Volt Power Distribution Panel (1 ea per
cabinet)
24 Volt Power Distribution Panel (1 ea per cabinet)
5/12 Volt Power Supply (up to 2 ea per cabinet
group)
The Power Distribution Panels (PDP), 19C852636P1,
distribute DC power to all Voter equipment installed in the
cabinet or rack. Each cabinet requires two PDPs for power
distribution. One PDP distributes the +5 and ±12 Vdc and
the other distributes the 24 Vdc. Both PDPs are identical,
except for the voltage labeling. A typical PDP is shown in
Figure 4.
Source voltage to the each PDP is supplied by either the
Redundant Power Supply System (RPS) installed in the
Voter cabinets or racks or from an external source provided
by the customer.
Refer to LBI-39153 for Interconnect diagrams showing
the power distribution within each cabinet and power
distribution between multiple cabinets.
Maintenance and accessory information for the PDP is
available in the PDP Maintenance Manual, LBI-39158.
POWER SUPPLIES
The Voter system requires +5, ±12, and +24 Vdc for
operation. This power is either provided from an external
source or by the Redundant Power Supply System (RPS)
installed in the Voter cabinets. A typical RPS, as shown in
Figure 5, includes a chassis and one or two power modules.
When using the RPS as the power source, it is necessary to
install one or two +5 and ±12 Vdc systems and a +24 Vdc
system including the following:
24 Volt Power Supplies (1 ea per cabinet group)
Figure 4 - Typical Power Distribution Panel (24 Volt model shown)
9
LBI-39149
•
•
VOTER EQUIPMENT
±12 Vdc RPS - 350A1441P1 chassis and
+5/±
350A1441P3 (+5/±12 Vdc) Power Modules.
Additional information on the RPS may be found in
LBI-39038.
24 Vdc RPS - 350A1441P2 chassis and
350A1441P5 (+24 Vdc) Power Modules.
VOTER UNIT
Normally the Voter system uses one or two +5/±12 Vdc
RPS system per Cabinet (rack) group, depending on the
number of Voter Units installed, and one 24 Vdc RPS
system per installation.
±12 Vdc RPS operates as an “N+1” redundant
The +5/±
system. This means that “N” power modules are required
for system load and an additional module “+1” is added to
provide redundancy. Each of the +5/±12 Vdc RPS power
modules share the current load and are capable of providing
up to 380 Watts per module. In the unlikely event one
module should fail, the remaining modules are capable of
providing system power.
The 24 Vdc RPS operates as a “2N” redundant system.
In this configuration, the modules are connected in parallel
with each module capable of supplying up to 360 Watts.
The current load is shared by the modules and in the
unlikely event one of the modules should fail, the other
module is capable of handling the entire load.
è ç12VDC
12VDC
+
The term “Voter Unit” refers the minimum voter
hardware required for voter operation. Each Voter Unit
consists of the following main elements:
•
•
Analog Voter Shelf (2 ea for 2-12 site system, 3 ea
for systems with 13-17 sites)
•
EDACS Interface Panel
•
Interconnect Cable Set
With the exception of the interconnect cables, these
elements are further defined in the following paragraphs.
For a description of the interconnect cabling, refer to the
Cable Connection lists, Cable Diagrams, and the Voter Unit
Interconnect Diagrams contained in LBI-39153.
è ç12VDC
12VDC
+
5V TEST
5V TEST
STATUS
TEMP
STATUS
TEMP
_
Digital Voter Shelf (1 ea)
_
±12 Volt Redundant Power Supply System
Figure 5 - Typical +5/±
10
12VDC
è ç12VDC
VOTER EQUIPMENT
Analog Voter Shelf
(rear view)
Analog Voter Shelf
Digital Voter Shelf
LBI-39149
VOTER UNIT
THREE (3)
EDACS Interface Panel
Analog Voter Shelf
Analog Voter Shelf
(rear view)
Analog Voter Shelf
Analog Voter Shelf
(rear view)
Digital Voter Shelf
VOTER UNIT
TWO (2)
EDACS Interface Panel
Analog Voter Shelf
Analog Voter Shelf
(rear view)
Analog Voter Shelf
Analog Voter Shelf
(rear view)
Digital Voter Shelf
Analog Voter Shelf
VOTER UNIT
ONE (1)
POWER
DISTRIBUTION
PANELS
24V Power Dist. Panel
5V/12V Power Dist. Panel
5V/12V Power Supply
(rear view)
5/12 Volt Power Supply
5/12 Volt Power Supply
EDACS Interface Panel
POWER
SUPPLIES
5V/12V Power Supply
(rear view)
24 Volt Power Supply
24V Power Supply
(rear view)
(Front View)
(Rear View)
Figure 6 - Typical 83-Inch Cabinet with Power Supplies
11
LBI-39149
VOTER EQUIPMENT
(GPTC), the Selector Configuration Plug, and
unique Selector programming.
Maintenance
information for the Selector is available in LBI39151.
Digital Voter Shelf
The Digital Voter Shelf, shown in Figure 7, furnishes
housing and electrical connections for the modules installed
in the shelf. The type and number of modules installed in a
Digital Voter Shelf depends on the type of system, number
of sites and channel configuration. For example, in a
Simulcast system the shelf may be configured for one
channel per shelf and support up to 17 sites or two channels
per shelf supporting a maximum of six (6) sites. Refer to
LBI-39153 for a listing of the various configurations.
A combination of the following modules may be housed
in the Digital Voter Shelf:
•
•
Digital Voter Shelf (188D6544P1) - The Digital
Voter Shelf is a standard VME Shelf with a
specially designed backplane. The backplane
distributes power from the Power Distribution
Panels to the modules. It also provides interfacing
between the modules and routes signals between
the modules and the EDACS Interface Panel.
Maintenance information for the VME Shelf and
backplane is contained in LBI-39150.
•
•
•
Selector(s) (ROA 117 2240/2) - Each shelf
requires a Selector (two (2) Selectors for two
channels per shelf configuration). The Selector
contains a General Purpose Trunking Card
RMIC
Digital Receivers (ROA 117 2240/1) - A Digital
Receiver is required for each corresponding
receiver site. The Digital Receiver contains a
General Purpose Trunking Card (GPTC), a Digital
Receiver Configuration Plug, and unique Digital
Receiver programming. Maintenance information
for the Digital Receiver is available in LBI-39151.
Rockwell Modem Intfc Card - (ROA 117
2247/1) - The Rockwell Modem Interface Card
(RMIC)
allows
for
modulated
signal
communication between the Digital Receivers or
Selector(s) and the remote or satellite sites.
Maintenance information for the interface cards is
contained in LBI- 39152.
RS-232 Interface Card - (ROA 117 2247/2) - The
RS-232 Interface Card provides a direct
communication link between the Digital Receivers
or Selector(s) and the Main Site equipment
(distance not to exceed 50 feet). Maintenance
information for the interface cards is contained in
LBI- 39152.
RS-232 INTFC CARD
SELECTOR
Figure 7 - Digital Voter Shelf
12
DIGITAL RCVR
VOTER EQUIPMENT
Analog Voter Shelf
•
The Analog Voter Shelf, shown in Figure 8, provides
continuous voting of satellite receivers and selects the
receiver with the best audio quality. The selected audio is
amplified and applied to the selector speaker and to the
phone lines.
•
The number of sites supported by the Voter System
determines the number of Analog Voter shelves and
modules required by each Voter Unit. As a minimum, each
Voter Unit contains two (2) Analog Voter shelves.
Each Analog Voter Shelf contains a combination of the
following subassemblies:
•
Analog Voter Shelf (19E500936G2) - The shelf
itself furnishes housing for the modules and
provides electrical connections via the backplane.
•
LBI-39149
Analog Receiver Module (19D903175G1) - The
Analog Receiver module receives and votes on the
site with the best audio signal. One Receiver
module is required for each corresponding Satellite
Receiver site.
Audio Module - (19D413958G5) - The Audio
module routes the selected Analog receivers signal
to the speaker and the Main Site. One Audio
module is required for each shelf.
Power Supply Module - (19D413917G4) - The
Power Supply module converts the 24 Volt source
voltage from the Power Distribution Panel into
regulated 20 and 24 Vdc. One Power Supply
module is required for each shelf.
For complete description and maintenance information
on the Analog Voter refer to LBI-38676. For information
on configuring the Analog Voter for operation in a CV2
system, refer to LBI-39153.
RECEIVER MODULES
AUDIO
MODULE
POWER SUPPLY
MODULE
ON/OFF
Switch
Figure 8 - Analog Voter Shelf
13
LBI-39149
VOTER EQUIPMENT
EDACS Interface Panel
The EDACS Interface Panel serves as a central
interconnect point for all signals entering or leaving a Voter
Unit and between the digital and analog shelves. It also
connects voice and data signals between the IMC switch and
the sites. These signals are routed to and from the EDACS
Interface Panel to the Voter’s Analog and Digital Cross
Connect Panels, located in adjacent cabinet, via 25-pair
TELCO cables.
The configuration of the EDACS Interface Panel
depends on the system configuration. Specifically, whether
the voter unit is configured for one channel or two Channel
per shelf applications.
The EDACS Interface Panel configured for use with the
CV2 system uses a combination of the following
subassemblies. A complete description and maintenance
information for each subassembly is available in LBI-39075.
•
Audio Interface Board (19C852204G1) - The
Audio Board routes audio signals to and from the
Analog Voters and routes signals to and from the
IMC (Integrated Multisite Controller).
•
Voter Digital Relay Board (188D6495G1) - The
Voter Digital Relay Board (VDRB) selects the type
of signal, analog or digital, to route to the IMC and
other equipment.
•
Digital Interconnect Board (ROA 117 2227 or
ROA 117 2228) - The Digital Interconnect Board
routes digital signals to and from the Digital Voter
and routes control signals between the Digital and
Analog Voters. ROA 117 2227 is for 2 Ch./shelf,
and ROA 117 2228 is for 1 Ch./shelf.
Figure 10 - Typical CV2 Interface Panel Configured for Simulcast One (1) Channel per Shelf
Figure 9 - Typical CV2 Interface Panel Configured for Simulcast Two (2) Channels per Shelf
14
CONTROLS AND INDICATORS
LBI-39149
CONTROLS AND INDICATORS
Table 2 - Selector Controls and Connectors
DIGITAL VOTER SHELF
CONTROL
PURPOSE
Selector
The Selector front panel indicators and controls are
described below.
The unlabeled LEDs (V13, V15, and V16) are
unassigned and will normally be OFF. However, if one of
the LEDs comes ON it does not necessarily indicate a
problem.
RST
(Green)
PROG
(RJ-12)
Reset button (S4)
Use to manually reinitialize Voter
software.
Programming Connector (X3)
Use to download the Voter software
from a PC to the Selector.
NOTE
NOTE
The numbers shown in parentheses refer to the
Selector’s circuit diagram reference designator.
Table 1 - Selector Indicators
INDICATOR
RDY
(Red)
PURPOSE
Ready indicator (V14)
ON - indicates the Selector’s programming code is functional and it is ready to
send and receive messages.
RDY
OFF - Selector communication error,
refer to Troubleshooting section in LBI39153.
CC
(Red)
Control Channel indicator (V11)
ON - indicates the Selector is operating
in the Control Channel mode.
OFF - indicates the Selector is operating
in the Working Channel mode.
XMIT
(Red)
S
E
L
E
C
T
O
R
CC
XMIT
SEL/F
RST
Transmit indicator (V10)
ON (flickering or flashing at a 1 Hz rate)
- indicates the Selector is sending
information to the Main Site.
PROG
OFF - Indicates a communication
failure, refer to the Troubleshooting
section in LBI-39153.
SEL/F
(Red)
Selector and Fault indicator (V12)
ON - indicates normal operation.
Figure 11 - CV2 Selector
OFF or Flashing - Off indicates a
module failure, flashing indicates a BSL
failure (2 Hz flash rate) or phone line
failure (1 Hz flash rate). Refer to the
Troubleshooting section in LBI-39153.
15
LBI-39149
CONTROLS AND INDICATORS
Digital Receiver
The Digital Receiver front panel indicators are
described below.
LBER
(Red)
MBER
(Red)
NOTE
NOTE
The numbers shown in parentheses refer to the
circuit diagram’s reference designator.
HBER
(Red)
RDY
(Red)
ON - indicates the BER is between 3 and
4.5%.
ON indicates the BER is greater than
4.5%.
PURPOSE
Table 4 - Digital Receiver Controls and Connectors
Ready indicator (V14)
ON - indicates the Digital Receiver’s
programming code is functional and the
receiver is ready to send and receive
messages.
OFF - Receiver communication error,
refer to Troubleshooting section in LBI39153.
CC
(Red)
zero (0) and 3%.
All OFF - indicates no BER value is
being sent to the Selector.
Table 3 - Digital Receiver Indicators
INDICATOR
ON - indicates the BER value is between
Control Channel indicator (V11)
CONTROL
RST
(Green)
PROG
(RJ-12)
PURPOSE
Reset button (S4)
Use to manually reinitialize Voter
software.
Programming Connector (X3)
Use to download the Voter software
from a PC to the Digital Receiver.
ON - indicates the Digital Receiver is
operating in the Control Channel Mode.
OFF - indicates the receiver is operating
in the Working Channel mode.
XMIT
(Red)
Transmit indicator (V10)
ON - indicates the Digital Receiver is
sending information to the Selector over
the Backup Serial Link (BSL).
Typically, the XMIT LED flashes at a 4
Hz rate which represents the required
250 millisecond status updates.
OFF - indicates a communication
failure, refer to the Troubleshooting
section in LBI-39153.
DR/F
(Red)
Digital Receiver and Fault indicator
(V15)
ON - indicates normal operation.
OFF or Flashing - Off indicates a
module failure, flashing indicates a BSL
failure (2 Hz flash rate) or phone line
failure (1 Hz flash rate). Refer to the
Troubleshooting section in LBI-39153.
RDY
D
I
G
R
C
V
R
CC
XMIT
DR/F
LBER
MBER
HBER
RST
PROG
The Bit Error Rate (BER) Indicators
(V12, V13, and V16) indicate the
calculated Bit Error Rate sent to the
Selector during a Digital Voice call.
Figure 12 - CV2 Digital Receiver
16
CONTROLS AND INDICATORS
LBI-39149
Rockwell Modem Interface Card
The 9600 Baud Rockwell Modem Interface Card's front
panel indicators are described below:
NOTE
NOTE
The numbers shown in parentheses refer to the
circuit diagram’s reference designator.
Table 5 - Rockwell Modem Interface Card Indicators
INDICATOR
+5V
(Red)
PURPOSE
+5 volt Indicator (V1)
ON - indicates fuse F1 is good and +5
Vdc (VCC) is being applied to the card's
circuitry.
OFF - indicates a problem, refer to the
Troubleshooting section in LBI-39153.
+5V
+12V
(Red)
+12 volt Indicator (V2)
ON - indicates fuse F3 is good and +12
Vdc (VDD) is being applied to the card's
circuitry.
OFF - indicates a problem, refer to the
Troubleshooting section in LBI-39153.
-12V
(Red)
+12V
-12V
RLSD
CTS
I
F
C
-12 volt Indicator (V3)
ON - indicates fuse F3 is good and -12
Vdc (VSS) is being applied to the card's
circuitry.
OFF - indicates a problem, refer to the
Troubleshooting section in LBI-39153.
RLSD
(Red)
M
O
D
E
M
EYE
Received Line Signal Detect indicator
(V12)
ON - indicates the modem receiver is in
the data state and receiving an input
signal of sufficient amplitude.
Figure 13 - CV2 Rockwell Modem Interface Card
OFF - indicates the modem receiver is in
the idle state and is not receiving an
input signal or the signal is too weak.
CTS
(Red)
Clear To Send indicator (V11)
ON - indicates the RM, responding to a
Request-to-Send (RTS) signal from the
Selector CPU, is set up and ready to
send data.
OFF - indicates RM is not ready to send
data.
17
LBI-39149
CONTROLS AND INDICATORS
ANALOG VOTER SHELF
The Analog Voter Shelf houses up to six receiver
modules, an audio module, and a Power Supply/Speaker
module.
Analog Receiver
The Analog Receiver modules have three LED
indicators, a mode selection switch, and the Input
Adjustment potentiometer. Table 6 describes the purpose of
each receiver indicator and control.
Table 6 - Analog Receiver Indicators and Controls
INDICATOR or
CONTROL
VOTED
(green)
RECEIVING
(amber)
FAILED
(red)
PURPOSE
Indicates the Satellite receiver
associated with
this
Analog
Receiver is the selected (voted) site.
Audio from this site is routed to the
main site repeater via the Audio
module.
Indicates the receiver is receiving
audio signals from its associated
Satellite Receiver.
Indicates a loss of signal possibly
resulting from a telephone line
failure between the Satellite and the
Analog Receiver or receiver
malfunction. Refer to LBI-38676.
Receiver is removed from the voting
process.
MODE SWITCH
This toggle switch selects the
receiver’s operating mode as
follows:
Select - manually selects
receiver as the voted site.
this
Normal - Allows the receiver to be
selected if it receives the best input
signal.
Disable - manually removes the
receiver from the voting process.
18
J1
Test Point for measuring level of
input signal.
INPUT ADJ
Adjusts the amplitude of input
signal during receiver alignment.
Figure 14 - Analog Voter Receiver
CONTROLS AND INDICATORS
LBI-39149
Audio Module
The audio module has a speaker Volume Control,
Output Level Adjustment, and Output monitor jacks, but no
indicators.
Table 7 - Audio Module Indicators and Controls
INDICATOR or
CONTROL
VOLUME
OUTPUT ADJ
LINE
PURPOSE
Adjust to speaker audio output.
Adjusts the amplitude of the output
signal sent to the Main site repeater.
Connections for
output signals.
monitoring
the
Figure 15 - Audio Module
19
LBI-39149
CONTROLS AND INDICATORS
GETC INDICATORS
Satellite Site GETC
GETCs are used at the Simulcast Control Point and
Transmit Sites, Main Site, and Auxiliary Receiver sites for
communicating with the Voter.
For reference, their
indicators are listed here.
For detailed operating
information, refer to the applicable GETC or Simulcast
configuration manual.
The list in Table 9 identifies the GETC indicators and
their functions when the GETC is used as Satellite Site
GETC.
Each GETC shelf has a row of seven LED indicators
across the front panel. The pattern of lit indicators shows
the function or state of the GETC. The following sections
describe the indicator states for different GETC applications
within the voter system. Detailed information on the GETC
shelf assembly can be found in the separate GETC
Maintenance and Configuration manuals.
Refer to the System Checkout section in LBI-39153 for
additional information describing the various operating
states of GETCs when communicating with a voted system.
Table 9 - Satellite Receiver & Simulcast TX Site
GETC Indicators
INDICATOR
L1
PURPOSE
Ready
ON indicates GETC is functioning and
ready to send and receive messages.
OFF - indicates a possible problem.
Refer to LBI-39153 and LBI-38988.
L2
Control/Working Channel Indicator
Main (Control) Site GETC
ON - indicates GETC is operating in the
Control Channel mode.
The list in Table 8 identifies the GETC indicators and
their functions when used as a Main (Control) Site GETC.
OFF - indicates GETC is in the Working
Channel mode.
Table 8 - Main (Control) Site GETC Indicators
INDICATOR
L1
L3
Not used.
L4
Channel Alarm
PURPOSE
ON - indicates a test call is in process. If
the indicator remains on, the channel has
failed.
BSL (Backup Serial Link)
ON - indicates communication is
occurring on the BSL, such as in Failsoft
operation.
OFF - indicates GETC communications
occur over the site controller serial
link(s).
L2 thru L5
L6
Low Speed Data Enabled - Used with
indicator L7 to indicate Control Channel
mode.
OFF - indicates Unassigned Working
Channel.
High Speed/Voice Path Indicator ON - indicates GETC is transmitting
high speed data (HSD).
OFF - indicates GETC is transmitting
clear voice on Working Channel.
20
L5
Not used.
L6
Low Speed Data Enabled ON - indicates Working Channel is
assigned.
OFF - Normally operation.
ON - indicates Assigned Voice channel.
L7
OFF - normal operation when no test
calls are being made.
OFF - indicates Unassigned Working
Channel.
L7
High Speed Data enabled ON - indicates GETC is transmitting
high speed data (HSD).
OFF - indicates no HSD (Voted
systems) or GETC is transmitting clear
voice on Working Channel (Simulcast
only).
SYSTEM OPERATION
LBI-39149
SYSTEM OPERATION
The Compact Vertical Voter (CV2) system is an integral
part of an EDACS Simulcast or Voted radio system.
Receivers at Satellite Sites, RF Sites, or the Main Site
forward audio and digital signals to the voter system for
processing. The Voter system selects (votes on) the site
with the best signals and relays the selected signals to the
Main or Control site and if required to the Dispatcher.
The following paragraphs explain the basic voter
operation and then the interaction of the CV2 system in a
Simulcast and Voted system.
VOTER SYSTEM
The Voter system provides voting on both analog and
digital signals. Analog voting involves selecting the site
receiver receiving the best Clear Voice (CV) transmission.
Digital voting involves selecting the site receiver receiving
the best Digital Voice, Data, or Digital messaging such as
Control Channel status and assignment messages.
The main components of the CV2 system are the Analog
and Digital Voter shelves. These shelves are grouped
together as a Voter Unit. A Voter Unit includes one Digital
Voter shelf and two or three Analog Voter shelves. If the
total number of sites is 12 or less, then two Analog Shelves
are necessary. If there are 13 to 17 sites, a third Analog
Voter shelf is added to the Voter Unit.
Each Analog Voter shelf consists of an Audio
Amplifier, a Power Supply module, and a number of Analog
Receiver modules. The number and position of the receivers
is determined by system requirements as defined in the
Voter Installation Manual, LBI-39153, Configuration tables.
Each Digital Voter shelf consists of one Selector per
channel and a Digital Receiver for each channel at each site.
The Digital Voter Shelf also includes communication cards
as required by the system’s configuration (see LBI-39153).
In addition to the components previously mentioned,
each Voter Unit includes an EDACS Interface Panel
installed behind the Digital Voter Shelf. The Interface panel
routes all signals between the shelves and between the Voter
Unit and the Simulcast or Voted system equipment.
Analog Voting
The main purpose of the Analog Voter is to select (vote
on) the site receiver with the best Clear Voice audio signal.
It then routes the voted audio to the Control Point
(Simulcast system) or the main site repeater (Voted system).
The Analog Voter functions under the control of the
Digital Selector and its corresponding Digital Receiver. The
Digital Selector controls the Analog Voter’s voted audio
output. The Digital Receiver controls the Analog Receiver’s
audio output whenever the site receiver is idle or not
receiving.
When the Analog Voter receives a Clear Voice signal it
informs the Selector (via the RCVNG LINE) that an Analog
Receiver is receiving a signal. The Selector queues the
Digital Receivers via the Backup Serial Link (BSL) to
process the call. Each Digital Receiver detecting valid high
speed data (HSD) from the Site GETC, unmutes (enables)
its corresponding Analog Receiver. It keeps the Analog
Receiver unmuted as long as it receives “Low Speed Data
Detected” messages from the Site GETC, or until the Site
GETC sends a channel drop message.
When an Analog Receiver is enabled, its signal is added
to the voting process. The Analog Voter then selects the
best audio signal among the enabled receiver modules and
routes it to the transmitter or the Dispatcher (see Dispatch
Console Interface) as voted audio.
During all types of calls, the Selector controls muting
and unmuting of the Analog Voter audio output. If the
Selector receives an unkey, a drop message, or two status
messages in a row with no low-speed data, it mutes the
voted audio output. The selector also mutes the Analog
Voter any time it detects a telephone line or BSL failure. If
the Selector receives a valid message requiring a Clear
Voice channel, it forwards the message to the Control Site
and unmutes the Analog Voter.
Digital Voting
Digital voting occurs when the channel is receiving a
digital signal. The channel may be operating in either the
Control Channel or Working Channel mode.
The Control Channel mode involves processing EDACS
system related messages such as channel requests, Status,
key and unkey, RF, Alarm, Special Key, and Special Call
Block messages. The Selector relays these messages to the
Control Site.
The Working Channel mode involves processing digital
information such as Digital Voice calls and Data Calls or
relaying EDACS system messages.
Site receivers send both Digital Voice and Data calls to
their corresponding Digital Receiver. The Digital Receivers
receive data from remote or Satellite receivers via an RMIC
(for modem data) or an RS-232 Interface Card (for serial
data), depending on the system configuration. The Digital
Receiver processes the information, maintains sync on the
data stream, and performs continuous Bit Error Rate (BER)
calculations during a Digital Voice call. During a Data call,
the site receiver performs an initial BER calculation. The
Digital Receiver then sends a Ready message to the Selector
over the BSL.
21
LBI-39149
SYSTEM OPERATION
The Selector continues the digital voting process by
simultaneously notifying all the remaining Digital Receivers
to begin their BER calculations and report the results via the
BSL. The Digital Receiver with the lowest BER value sends
the voted output to the Selector. In the event of two or more
equal BER values, the Digital Receiver with the lowest slot
time number is voted.
The Selector receives the voted output from the Digital
Receiver via the BSL and relays it to the Main Site GETC,
Control Point Trunking Card or Control Point GETC, or
Dispatcher, depending on system requirements and
configuration.
The Selector also expects the Digital Receivers to relay
a status message containing their current status and status of
DIGITAL VOTER SHELF
RMIC
Receive Data From
Base Station and
Satellite Receivers
Squelch To Analog
Rcvr "N"
Digital
Receiver
"N"
•
•
•
BSL
Digital
Receiver
"2"
RMIC
Digital
Receiver
"1"
RMIC
or
RS-232
Squelch To Analog
Rcvr "2"
Squelch
To Analog Rcvr "1"
Digital Selector
Voted Data
Receiving signal from Audio Module
Mute to Audio Module
VDRB
Data to
GETC
ANALOG VOTER SHELF
Squelch
Squelch
Receive Analog
From Base Station
and Satellite Rcvrs
Audio to
Transmitter
Receiver
Module
"N"
•
•
•
Mute from
Digital Selector
Receiver
Module
"2"
Audio Module
Voted Audio
Squelch
Receiver
Module
"1"
Console
Receiving signal to
Digital Selector
CEC/IMC
Voted Audio or Data
Console Audio or Data
Figure 16 - Simplified Voter Block Diagram
22
SYSTEM OPERATION
their corresponding site receiver. In addition, each receiver
appends its status message to include the site’s number and
sends the message via the BSL to the Selector. The
receivers send the messages at 250 milliseconds intervals,
provided no other digital messages need to be sent. If a
receiver receives an Alarm or RF message, it sends the
message to the Selector immediately. Alarm and RF
messages have a higher priority than status messages.
LBI-39149
During Clear Voice calls originating from a Dispatch
Console, the VDRB routes audio and data from the
CEC/IMC to the Simulcast or EDACS Voter System. Voted
audio is routed to the Simulcast Audio equipment or
EDACS transmitter and Voted Data is routed to the Control
Point Trunking Card or Station GETC for processing.
During Digital Voice or Data calls from the originating
site, Voted data is routed to the Control Point Trunking Card
(Simulcast) or Station GETC and the CEC/IMC for console
monitoring.
The Selector echoes the status messages, including the
site number, on the BSL for other Digital Receivers to hear.
The Digital Receivers use site number information to
determine if the message on the BSL is their own.
Digital Voice (also refered to as Digital Dispatch) or
Data from the console is routed through the CEC/IMC to the
Simulcast Control Point Trunking Card or EDACS Station
GETC. The VDRB also routes Voted data to the IMC so
the console can answer message trunked calls.
Dispatch Console Interface
EDACS Simulcast or Voted systems may also interface
with Dispatch Consoles. The consoles are linked to the
system via the Console Electronic Controller (CEC) or
Integrated Multisite and Console Controller (IMC).
SIMULCAST SYSTEM
A Simulcast System consists of a single Control Point
and two or more RF sites as shown in the simplified block
diagram in Figure 18.
The CV2 system uses a Voter Digital Relay Board
(VDRB) to route analog and digital traffic to and from the
CEC/IMC and Dispatch Console as shown in Figure 17.
This traffic can be clear voice, data calls, digitized voice or
encrypted voice (Voice Guard or Aegis). The CEC/IMC
and Selector control the VDRB and route the signals as
described in the following paragraphs. Refer to LBI-39075
for a complete circuit analysis of the VDRB’s operation.
Control Point
The Control Point is co-located with the Voter and
makes the Voter an integral part of the Simulcast System.
However, the Control Point does not contain transmit or
receive equipment, so all Transmit-Receive Sites are
considered remote, even if one is co-located with the
Simulcast Control Point. Data and Voice signals are
brought to the Voter Digital and Analog Receivers via a T1
inter-site communication link (microwave, leased lines, or
fiber optic) and multiplex (MUX) equipment at the Control
Point and Transmit-Receive Sites.
During Clear Voice calls originating from a site, the
voted audio is routed through the VDRB to the Simulcast
Audio distribution equipment or EDACS Station transmitter
for repeating and to the CEC/IMC for monitoring by the
Dispatch Console. Voted data is routed to the Simulcast
Control Point Trunking Card or Station GETC for
processing.
VG From Selector
DISPATCH CONSOLE
Voted
Audio
Voted
Data
CEC/IMC
Control
AUDIO
TOWER
Audio
CIM
Controller
Board
CIM
Audio
Board
TDM Bus
MIM
Controller
Board
MIM
Audio
Board
PTT (Console Key)
Voted Audio/Data
Voter
Digital
Relay
Board
Data to GETC
Audio to Tx
Audio/Data Output
Figure 17 - Simplified CEC/IMC To Voter Block Diagram
23
LBI-39149
SYSTEM OPERATION
Voted voice and data signals are routed to the Control
Point Trunking Card for processing by the Simulcast
equipment and distribution to the Transmit-Receive Sites.
The voted voice is the Simulcast repeat audio source, the
voted data is the voted digital voice source and path for
trunking data messages to the Control Point Trunking Card.
In the Control Channel mode, the site receiver receives
outbound Control Channel messages from its Control
Channel Monitor via the Backup Serial Link (BSL). These
messages include operating mode, call type, and Control
Channel slot timing information. Loss of Control Channel
data may cause the site receiver to miss messages.
In the Simulcast system, the Control Point coordinates
the activities of the RF sites and the Voter system. the Voter
Selector listens to the data messages from the Control Point
Trunking Card. These messages indicate the Control Point
Trunking Card’s current operating mode, such as, Control
Channel, Clear Voice Working Channel, and Digital Voice
Working Channel. The Selector transmits to the Control
Point Trunking Card in the RM (Rockwell Modem) mode,
but receives from the Control Point Trunking Card in the
RS-232 mode. This link is provided through a specially
modified RMIC (Mod Kit 350A1693G1) which transmits in
the RM mode and receives RS-232.
When operating as a Working Channel, the site receiver
GETC monitors the outbound Control Channel messages
from the Control Channel Monitor via the BSL. It then
searches for the corresponding inbound message on the RF
port. When the expected signal is detected, the message and
associated voice audio (digital or analog) is relayed to the
voter.
In the Simulcast system, Digital Receiver #1 listens to
data from the Site 1 Receiver GETC.
NOTE
NOTE
When no audio is being received, each receiver site
keeps the analog communication link active by
generating a holding tone (1950 Hz for the Analog
Voter). When no digital signals from the radio
system are being received, each Site GETC keeps
the digital communication link active by generating
status messages for the Digital Voter.
The site receiver also generates a 1950 Hz tone. This
tone is sent to the Analog Voter whenever the channel is
unassigned and no carrier or low speed is present. This
causes the Analog Voter to mute (remove from the voting
process) the associated Analog Receiver module. If the site
receiver receives a key message or low-speed signaling from
a radio unit it disables the tone, allowing the output of the
Analog Receiver to be voted on.
Control Channel Monitor
A Control Channel Monitor is located at each Transmit
Site to detect and pass control and status messages to the site
receiver GETCs via the BSL. This keeps the system in sync
with the trunking system Channel assignment activity and
operating modes. The receiver GETC will not pass Digital
Voice traffic to the Voter if the Control Channel Monitor is
not operating.
A Simulcast Transmit site is equipped with
transmitter/receiver, Simulcast MUX equipment, Control
Channel Monitor, and Receiver GETC.
The Transmit Site Control Channel Monitor also
functions as part of the Simulcast System Test Call process.
It sets up the receiver GETC so it’s ready to receive a Test
Call from the Test Unit on site. The digital messages from
the Test Unit are processed by the receiver GETC and
passed to the Digital Voter for call processing.
Transmitter and Simulcast Equipment
Satellite Receiver Site
The transmitter is controlled by the Simulcast Control
Point signals routed through the inter-site communications
system and the MUX equipment. The receiver voice and
data signals are passed back to the Voter through the same
MUX equipment. The site receiver GETCs are configured
for Simulcast operation and do not trunk.
A Satellite Receive Site is added to a Simulcast system
if additional receive coverage is needed beyond that
available from the receivers at the Transmit Sites. The
Satellite Receiver GETCs are set up for the Satellite
Receiver mode and do not trunk. The Satellite Site works in
the same manner as the Simulcast Transmit Site receive
portion. It contains a Control Channel Monitor for the same
purpose as the Simulcast Transmit Site, except no Test Calls
are made at the site.
Transmit Sites
Receiver
The main function of a site receiver is to receive and
validate inbound status messages and audio from radio units
and pass the messages and receive audio to the Voter. The
Voter passes valid messages to the Control Point equipment,
discards duplicate messages, and votes on the analog and
digital voice signals.
24
SYSTEM OPERATION
LBI-39149
VOTER
Site Controller
Digital Receiver #1
BSL
Digital Receiver #n RM
CONTROL POINT
Control Data
(RS232)
Selector
PTT
Control Point
Trunking Card
RMIC
Analog
Voter
n
Simulcast
Equipment
1
PTT
TX Data
VG
Voted
Data
RX Data
Voted
Audio
Voter Digital Relay Board
Control Point
MUX
RX Voice Equipment
TX Voice
Console or
Voted Data
Console or
Voted Audio
PTT
TX Site
MUX
Equipment
CEC/IMC
Console
TX Data
RX Voice
Receiver
TX Voice
RX Voice
Rx GETC
RM
RX Data
TX Site
Simulcast
Equipment
RX Data
Transmitter
Receiver
Rx GETC
SITE 1
SITE n
(AUX RCVR)
From Control
Channel Monitor
RMIC
Control
Audio
Data
Modem
Intfc Card
From Control
Channel Monitor
Figure 18 - Simplified Voter Signal Flow (Simulcast System) Diagram
25
LBI-39149
SYSTEM OPERATION
The major components at the Satellite Site are shown in
Figure 19. Control Channel and Working Channel RF
signals are fed from the antenna to the multicoupler. The
multicoupler feeds all receivers. Each channel receiver is
connected to a GETC shelf. The Control Channel Monitor
receiver is connected to a buffer board, which connects to all
the receiver GETCs via the BSL.
distributes them to all satellite receiver GETCs located at the
site via the BSL at 19.2 kilobaud.
During an analog call, the receiver sends the received
audio signal to its corresponding Analog Voter receiver. If
there are no analog calls, the receiver sends a 1950 Hz tone
to the Analog Voter receiver. During a digital call, the
receiver provides the Receiver GETC with the received
digital signal. The GETC sends the received data to the
Digital Voter while maintaining the voting tone to the
Analog Voter.
Voted Digital Interconnect (Simulcast)
Control Channel Monitor
Only Simulcast systems with the Digital Dispatch
option can be equipped with the VDI option. When the VDI
option is installed, a digital path is added between the Voter
Selector and the Control Point Trunking Card. This path
allows the Control Point Trunking Card to listen to both the
CEC/IMC and the Voter simultaneously. See Figure 20.
The Control Channel Monitor at the Satellite Site is a
mobile radio which monitors the outbound Control Channel
messages from the Main Site. This radio receives and
validates the slotted outbound control messages. The
monitor routes the data messages to the Buffer Board which
The Simulcast Control Channel Monitor uses a separate
directional antenna so it will receive the RF signals from
only one Simulcast Transmit Site. This reduces the
interference from other Simulcast Sites.
The Voted Digital Interconnect (VDI) option allows a
Simulcast system to have access to the Jessica Private
Branch Exchange (PBX) Gateway, known simply as Jessica.
Jessica is a centralized digital communications gateway
connected to the CEC/IMC that links an EDACS radio
system to the local Public Switched Telephone Network
(PSTN).
(Directional Antenna
Simulcast systems only)
or
SIGNAL
SAMPLER
(EDACS Satellite
Receiver systems)
AUDIO
PANEL
MASTR III MULTIPLE
RECEIVER
MULTICOUPLER
CONTROL
CHANNEL
MONITOR
Mob
Data Out
BUFFER
BOARD
Control
CC Data
Data
DATA
PANEL
BSL
TX CLK
REF CLK
RECEIVER GETC
GETC Data
Out
Figure 19 - Typical Satellite Receiver Site Block Diagram
26
Audio Signals
To Analog
Voter Receiver
Line Out
Data Signals
To Digital
Voter Receiver
and Selector
SYSTEM OPERATION
LBI-39149
VOTER
Site Controller
Digital Receiver #1
BSL
Digital Receiver #n RM
CONTROL POINT
VDI (RS-232)
RS-232
Selector
PTT
Control Data
(RS232)
Control Point
Trunking Card
RMIC
Analog
Voter
n
Modem
Intfc
1
Simulcast
Equipment
PTT
TX Data
Voted
Data
VG
RX Data
Voted
Audio
Control Point
MUX
RX Voice Equipment
TX Voice
Console or
Voter Digital Relay Board Voted Data
Console or
Voted Audio
PTT
Console
TX Site
MUX
Equipment
DVIU
CEC/IMC
Jessica
TX Data
RX Voice
Receiver
TX Voice
RX Voice
Rx GETC
RM
RX Data
RX Data
TX Site
Simulcast
Equipment
Transmitter
Receiver
Rx GETC
SITE 1
SITE n
(AUX RCVR)
From Control
Channel Monitor
RMIC
Control
Audio
Data
Modem
Intfc Card
From Control
Channel Monitor
Figure 20 - Simplified Voter Signal Flow (Simulcast System with Digital Dispatch & VDI) Diagram
27
LBI-39149
SYSTEM OPERATION
EDACS (NON-SIMULCAST) VOTER
SYSTEM
The EDACS (non-Simulcast) system includes a main
transmit/receive site, a number of receive-only Satellite
Sites, and a centrally located CV2 system with Digital and
Analog Voters.
The Satellite Sites and Main Site transmit site receive
signals on their RF ports and relay these signals to their
corresponding Analog and Digital Receivers. The Analog
and Digital Voters work in parallel to vote digital and
analog signals. The Selector relays voted digital signals to
the Main Site GETC and directs the Analog Voter to relay
voted audio signals to the Main Site transmitter.
Main Site
Main Site equipment (Figure 21) in an EDACS (nonSimulcast) Voter system is basically the same as in a nonvoted EDACS system. However, in a voted system, two
pairs of telephone lines are required per channel. This
allows the receivers to transfer both data and voice to the
Voters simultaneously.
The audio voice paths are connected to the back of the
MASTR III station T/R Shelf. Repeater audio is available at
the line audio pair connected to the voter, and audio from
the voter is connected to the remote duplex audio input pair.
RECEIVER
MULTICOUPLER
The Main Site GETCs (those that control the RF
transmit function of the EDACS) must be configured for
voted operation. The GETC configuration is based on the
data programmed into the GETCs personality, the presence
or absence of a Clear-to-Send (CTS) signal, and on the
presence of continuous messaging from the voter.
Typically, the CV2 system is co-located with the Main
Site equipment and data paths to and from the voter are
separate lines with signals at RS-232 levels. The Main Site
GETC is strapped (jumper connected from TB10-1 to 5)
providing the GETC with a continuous CTS signal.
If the Main Site is at a remote location, data paths to
and from the Main Site GETC are via modem. The CTS
signal is supplied by the RM in response to a Request-toSend (RTS) signal.
Once the Main Site GETCs are configured for voted
operation, all working-channel messages received locally by
the Main Site GETCs are simply passed down to the Voter.
Digital messages received from the voter determine the
GETCs call operation. Messages received by the Main
Site's Control Channel are acted upon immediately, and
redundant messages are discarded.
TRANSMITTER
COMBINER
AUDIO
PANEL
TRANSMITTER
RECEIVER
Control
RX
Data
Audio In
Voted Audio or Console
Audio via VDRB
Audio Out
Audio Signals To
Analog Voter Receiver
DATA
PANEL
TX
Data
GETC TX Data
RECEIVER GETC
GETC RX Data
Out
Figure 21 - Main-Site Equipment (Single Channel)
28
Voted Data or Console Data
via VDRB
Data Signals To Digital
Voter Receiver and Selector
SYSTEM OPERATION
LBI-39149
VOTER
MAIN SITE
Digital Receiver #n RM
Receiver
BSL
Digital Receiver #2 RM
Transmitter
Digital Receiver #1
RM
Selector
RM Main Site GETC
VG
Analog
Voter
1
2
n
Site Controller
Control
Audio
Data
Rockwell Modem
Voter Digital Relay Board
RM
PTT
Console Switch
Console
Receiver
Rx GETC
Receiver
RM
SITE 2
From Control Channel Monitor
RM
Rx GETC
SITE n
From Control Channel Monitor
Figure 22 - Simplified Voter Signal Flow (EDACS Non-Simulcast System) Diagram
29
LBI-39149
SYSTEM OPERATION
If the stream of messages from the Voter ceases, the
Main Site GETCs revert to a mode where they act upon
locally received messages immediately, yet continue to
transmit all locally received messages to the Voter. If no
CTS signal is received, then the Main Site GETCs operate in
single-site mode.
In the Working Channel mode, when the Main Site
receives the radio's transmission, it sends a key message and
then begins sending received audio to the Voter. (The key
message tells the Digital Receiver to unsquelch its receiving
unit.) The audio is routed to the Analog Voter where it is
voted on before being relayed to the Main Site transmitter.
When no calls are in progress, a mute tone is inserted
onto the audio line by the Main Site. The tone is present at
all times, except when the channel is assigned and both
carrier and low-speed data are present. A tone detection
circuit at the corresponding Analog Voter Receiver module
mutes its audio path whenever the mute tone is present.
30
NOTE
NOTE
When no audio is being received, each receiver site
keeps the analog communications link active by
generating a holding tone (1950 Hz) for the Analog
Voter. When no digital signals from the radio
system are being received, each site GETC keeps
the digital communications link active by
generating status messages for the Digital Voter.
Satellite Site
Satellite Receiver operation in a non-Simulcast Voter
system is identical to that in a Simulcast system. The only
difference being the Control Channel Monitor RF input. In
a non-Simulcast Voter, the RF input to the Control Channel
Monitor is coupled from the Signal Sampler located between
the multicoupler and the antenna (see Figure 19).
SYSTEM OPERATION
Voted Digital Interconnect (Non-Simulcast)
The Voted Digital Interconnect configuration allows
voted sites to have access to the Jessica Private Branch
Exchange (PBX) Gateway.
For an voted (non-Simulcast) system, an additional
GETC per channel is required, making the configuration
more like that of a Simulcast system. The Main Site is
reconfiguration to add a Control GETC to the Voted System
as shown in Figure 20.
All GETCs attached to RF receivers will operate as
Satellite Receivers, and the added Control GETC will take
on transmit responsibilities similar to those of the Simulcast
Control Point Trunking Card. The main purpose of the
additional GETC is to provide a synchronous data input port
RECEIVER
MULTICOUPLER
LBI-39149
which can be connected to the output of the voter. This
provides the Control GETC the capability of listening to
both the IMC and the Voter simultaneously.
Basically, the system functions similar to a Simulcast
system (refer to Figure 24) with a co-located transmit site.
The major difference is the interface from the output of the
Control GETC to the Selector. The Selector RMIC transmit
pair is connected to the Main Site Receiver's Rockwell
Modem. From the Receiver GETC, Rockwell modem
output TTL data is connected to the Control GETC on the
Control GETC's free Amps Modem input. This establishes a
permanent connection from the Selector output to the
Control GETC. Thus, the Main Site now has access to both
IMC and selector data.
TRANSMITTER
COMBINER
AUDIO
PANEL
Voted Audio or
Console Audio via
VDRB
Audio Input
TRANSMITTER
TX Data
CONTROL
GETC
GETC TX Data
Modem Data
DATA
PANEL
Voted Data or Console
Data via VDRB
VDI Harness
19B804235
Modem Data To
Digital Selector
RECEIVER
RX Data
RECEIVER
GETC
Data Signals To Voter
Digital Receiver
GETC RX Data Out
Voted Data From
Digital Selector
Audio Out
CONTROL
CHANNEL
MONITOR
AUDIO
PANEL
CC Data
Audio To Analog Voter
Receiver
Figure 23 - Typical Main Site (Non-Simulcast ) Voted Digital Interconnect Block Diagram
31
LBI-39149
SYSTEM OPERATION
Main Site
BSL
RM
Digital Receiver #n RM
Receiver
Digital Receiver #2 RM
Digital Receiver #1 RM
PTT
Selector
Transmitter
RM
RM Control GETC
VG
Analog
Voter
1
2
Receiver GETC
n
Site Controller
Control
Audio
Data
Rockwell Modem
Voter Digital Relay Board
RM
PTT
CEC/IMC
Console
Receiver
Rx GETC
Receiver
RM
Site 2
From Control Channel Monitor
RM
Rx GETC
Site n
From Control Channel Monitor
Figure 24 - Simplified Voter Signal Flow (EDACS Non-Simulcast System With VDI Option) Diagram
32
RELATED PUBLICATIONS
LBI-39149
RELATED PUBLICATIONS
LBI-39074
-
The following publications provide additional
information on equipment associated with the EDACS
Compact Vertical Voter System.
MASTR
Manual.
LBI-39075
-
Interface
EDACS
CV2
Maintenance Manual
III
EDACS
Installation
Panel
LBI-38430
-
MASTR IIe
Manual.
Station Maintenance
LBI-39090
-
Simulcast Transmit Site Maintenance
Manuals.
LBI-38662
-
EDACS
Console
Electronics
Controller (CEC) and Integrated
MultiSite and Console Controller
(IMC) Digital Audio Switch
LBI-39112
-
MASTR III Multiple
Maintenance Manual
LBI-39142
-
EDACS Voter Cross Connect Panel
Maintenance Manual
LBI-39149
-
EDACS Compact Vertical
(CV2) Maintenance Manual
LBI-39150
-
EDACS CV2 Digital Voter Shelf
Maintenance Manual
LBI-39151
-
EDACS CV2 Digital Receiver &
Selector Maintenance Manual
LBI-39152
-
EDACS CV2 Rockwell Modem & RS232 Intfc Card Maintenance Manual
LBI-39158
-
EDACS Power Distribution Panel
Maintenance Manual
LBI-39186
-
Simulcast Control Point Maintenance
Manuals
LBI-38676
-
Analog Voter Maintenance Manual
LBI-38894
-
GETC Trunking Card Maintenance
Manual for 19D901868G3 and G4.
LBI-38988
-
EDACS Station GETC Configuration
Manual.
LBI-39000
-
EDACS Jessica
Systems Manual
PBX
Gateway
LBI-39031
-
EDACS StarGate Controller Digital
Audio Switch Maintenance Manual
LBI-39038
-
EDACS Redundant Power Supply
System Maintenance Manual
LBI-39041
-
EDACS CEC/IMC Digital Dispatch
DVIU
Equipment
Maintenance
Manual
LBI-39062
-
EDACS C3 Maestro Console System
Maintenance Manual
Receiver
Voter
33
LBI-39149
GLOSSARY
Backup Serial
Line
The Backup Serial Line is a data bus
used for communications between
GETCs during Failsoft Trunking. It is
connected to each Station, Downlink,
and Uplink GETC in an EDACS
system.
Bit Error Rate
(BER)
The average rate of errors on a radio
channel, usually expressed as a percent
(e.g., a 5% error rate indicates an
average of 1 error in every 20 bits
transmitted).
BSL
See Backup Serial Line.
Console
Communication equipment which
provides an operating position for a
dispatcher.
Control Channel
EDACS
Frame Sync Line
FSL
An EDACS Trunked System channel
over which system control information
is continually transmitted and channel
request/status information is received
form the field radio units. Field radios
monitor the Control Channel when not
assigned to a Working Channel.
EDACS, short for Enhanced Digital
Access Communications System, is a
registered trademark of Ericsson Inc. It
is used by Ericsson to describe specific
communications systems and their
specific equipment which meet or
exceed the needs of the Public Service,
Industrial, Commercial, and Utility
markets world-wide.
The Frame Sync Line is a +13.8 VDC
bus, with periodic negative pulses (to 0
VDC), sent from the Control Channel
GETC to the Working Channel
GETCs for synchronizing messages to
mobiles.
GETC
Ericsson GE Trunking Card - performs
the RF signal processing for the
repeater station. It re-synchronizes the
data information received by the
repeater station, processes it and sends
it back to the repeater station for
transmission
Multisite
A network of multiple EDACS
systems. Each system networked may
have a different number of working
channels.
Rockwell Modem
Interface Card
(RMIC)
Communication interface card with a
Rockwell Modem daughter board.
Used to transfer information along
analog paths such as phone lines
where bandwidth is <3000 Hz.
RS-232 Interface
Card
Communication interface card used for
transferring serial data between two
units within 50 feet of each other.
Simulcast
Simultaneous Broadcast by two or
more transmitters located at different
sites operating on the same RF
frequency.
Trunking
The process of dynamically allocating
a limited number of radio channels to
groups of people for communication
purposes.
Voter Digital
Relay Board
(VDRB)
A board in the EDACS Digital Voter
that allows either Clear Voice or
Digital Voice to be routed to an IMC
for multisite or digital dispatch.
Voting
The process of selecting the best
received signal for processing.
Working
Channel
A Working Channel is any radio
channel at an EDACS Trunked Site
that is available or in use to carry
trunked calls.
See Frame Sync Line.
Ericsson Inc.
Private Radio Systems
Mountain View Road
Lynchburg, Virginia 24502
1-800-528-7711 (Outside USA, 804-528-7711)
Printed in U.S.A.