Raven M4x User manual

Lit. No. M100V Rev. A 1/3/11
RAVEN ELECTRONICS CORPORATION
M4x
SNR Voter/Comparator
User Manual

2 Lit. No. M100V Rev. A 1/3/11
Table of Contents
Chapter 1: Raven M4x SNR Voter/Comparator Features ............................................................................................ 4
Chapter 2: Raven M4x SNR Voter/Comparator Hardware Interface.......................................................................... 5
Chapter 3: Creating a Raven SNR Vote Group Using the M4x Software.................................................................. 8
3.1 Using the Wizard to Create a Raven SNR Vote Group...................................................................................... 8
3.2 Manually Modifying a Raven SNR Vote Group.................................................................................................. 17
Chapter 4: Modifying the Configuration of a Member of a Raven SNR Vote Group.............................................. 18
4.1 Modifying a Receiver’s SNR Settings.................................................................................................................. 19
4.2 Modifying a Transmitter’s Keying Options.......................................................................................................... 20
Chapter 5: Raven SNR Vote Group Status................................................................................................................... 22
Chapter 6: Saving M4x Blade Configurations............................................................................................................... 23

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Contact Raven
Thank you for purchasing the M4x Blade from Raven Electronics Corporation. Please contact us if you have
any questions, concerns, product ideas, or suggestions on how to improve this manual. We can be contacted
at:
Raven Electronics Corporation
400 Edison Way
Reno, Nevada 89502
[phone] Phone
[phone]
[phone] Fax
[email protected]
[email protected]
ESD Handling
Please follow static-safe ESD guidelines when handling this product.
Raven Electronics’ Warranty
This warranty expressly precludes any liability by Raven for consequential damages however arising after
delivery to the purchaser of the affected equipment, and is limited to the expressed warranty, excluding all
implied warranties including merchantability. All equipment manufactured by Raven is warranted against
defective materials and workmanship for a period of two (2) years from the date of delivery to the original
purchaser or end-user. Liability under this warranty is limited to servicing, adjusting, repairing or replacing, as
necessary, any equipment returned to the factory, transportation prepaid for that purpose. Factory examination
must disclose a manufacturing defect. Repaired or replaced items will be returned to the purchaser surface
freight prepaid within the continental U.S.A. This warranty does not extend to any equipment which has been
subjected to transportation damage, misuse, neglect, accident, improper installation, or any other
circumstances reasonably beyond the control of Raven.
Beyond the warranty period, repairs will be billed to the purchaser at cost. In such cases, an estimate will be
submitted for approval before repair is initiated. Repaired equipment will be returned to the purchaser with
transportation charges collect, unless agreed to between the purchaser and Raven.

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Chapter 1: Raven M4x SNR Voter/Comparator Features
Receiver voting provides a method of expanding coverage for a radio network. Receivers in the network are
routed to a central voting system which votes the receiver with the best quality audio, and routes the voted
audio to a console or to other repeaters.
The Raven M4x SNR Voter/Comparator product is a special version of the Raven M4x Blade (shown on the
front cover of this manual). The Raven M4x Blade can be licensed to enable the creation of SNR (signal-to-
noise) vote groups. The licensing basically “turns on” the SNR feature which allows the audio from receivers to
be analyzed to determine its quality; the quality level is translated into a value (in decibels) that is used to
compare the quality of audio between different receivers. The receiver with the highest SNR value is chosen
as the “voted” receiver.
“Raven M4x SNR Voter/Comparator” and “Raven M4x Blade” are used interchangeably in this manual.
A Raven SNR vote group is created using the Raven M4x Communication System Software provided with the
Raven M4x Blade. There are a number of features that can be software-configured to create a vote group
tailored to a specific network. These features include:
•Automatic transmitter steering
•Manual transmitter steering
•Default transmission
•Flexible audio routing to any transmitter based on which receiver is voted
•Console priority
•Voting that commences based on status tone, COR, or VOX threshold
•Lack-of-audio timeout for voted receivers
•Keying of transmitters/repeaters with keying tones or with PTT
•Visual representation of voting activity for each member of the vote group
•Sub-comparators can be created and fed into a main vote comparator to create large vote groups
The Raven M4x Communication System Software also contains a wizard to help walk the user through the
individual steps involved in building a vote group. Once vote groups are created and saved, the vote group
can later be modified (using the M4x Software) either manually, or via the wizard. Additionally, multiple,
unrelated, vote groups can be created on a single Raven M4x Blade. Further, vote group configurations can
be “burned” to the flash memory on the M4x Blade so that a host PC isn’t needed to control the vote group.

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Chapter 2: Raven M4x SNR Voter/Comparator Hardware Interface
A Raven M4x Blade can house up to 4 Raven-manufactured, DSP-based (digital signal processing)
communication modules (see Figure 1). The types of modules can be mixed and matched to tailor the M4x
system to a particular need. Raven Electronics manufactures a number of different types of modules to
interface to radios (or other 4-wire devices), 2- and 4-wire telephones, the public telephone network, and other
types of communications equipment. Each M4x Blade is a USB device that can accept commands from a host
computer. The host computer can also respond to different events that occur on a particular port.
A Raven M4x SNR Voter/Comparator generally uses either the Raven 476-150 or 476-151 4-wire E&M
modules. The 476-150 module has a 600 ohm, 300-3400Hz interface; the 476-151 has a 600 ohm or high
impedance input (software-selectable), a 600 ohm output, with a 5-3400Hz frequency range. The Raven 476-
150/151 4-wire E&M module is used to interface to 4-wire communication equipment. Each 476-150/151 4-
wire E&M module supports two ports of audio.
The main function of the 476-150/151 4-wire E&M module is to convert analog audio to the digital domain on
one end and back to analog on the other. Once the audio is converted to the digital domain, it can be bridged
with any other port in the system using the switching fabric provided by the backplane upon which the M4x
modules ride. The 476-150/151 4-wire module can also provide the following features via software commands
from the host computer:
•Notch filtering
•Level control
•PTT generation (for radios)
•COR detection (for radios)
•Audio delay
•Tone Detection (including DTMF and single tones)
•Tone Generation (single tones, call progress tones, DTMF)
•Signal-to-Noise Ratio Analysis for voting applications
Raven 476-150/151 4-Wire E&M Modules

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Figure 1. Raven M4x Blade with Cover Removed
The Raven M4x SNR Voter/Comparator takes advantage of the 476-150/151 module’s Signal-to-Noise Ratio
Analysis feature to synthesize a simple, software-configurable voting product. A Raven M4x SNR
Voter/Comparator is expandable simply by adding additional modules, and configuring those modules with the
Raven M4x Software.
Physical connection to an individual port is made via an RJ45 connector available on the front of the M4x
Blade. Each 476-150/151 4-wire RJ45 port has the following connections:
•2 wires for analog receive
•2 wires for analog transmit
•2 wires for the PTT relay switch closure
•2 wires for the COR input
RJ-45 port pin number
M4x Blade Signal
Direction (with respect to the M4x Blade)
1
RX-A
Input
2
RX-B
Input
3
PTT
Output (switch closure)
4
TX-A
Output
5
TX-B
Output
6
PTT return
Output (switch closure return, optionally
ground-able via jumper)
7
COR
Input (active low)
8
COR GND ref
Ground reference
Figure 2. Pinout for a Raven M4x 476-150/151 Module
There’s a USB port on the rear of the Raven M4x Blade. This USB port is used by the Raven M4x
Communication System Software to control and configure the M4x Blade. The M4x Blade is powered by a
source of 9 to 18VDC; the power connector is also on the rear of the M4x Blade. See Figure 3.
Pin 1 Pin 8 Pin 1 Pin 8

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Figure 3. Raven M4x Blade Rear Panel Power and USB Connections

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Chapter 3: Creating a Raven SNR Vote Group Using the M4x Software
To create a Raven SNR Vote Group, start the Raven M4x Software and attach to the Raven M4x Blade (as
explained in the Raven M4x Communication System user manual).
3.1 Using the Wizard to Create a Raven SNR Vote Group
STEP 1
To create an SNR Vote Group, click on “Add
Vote Group” in the System Components
tree.
STEP 2
A wizard window appears to help you build
and configure the SNR Vote Group. Click
“Next” to continue.

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Note: You can designate more than 1 console connection if necessary.
STEP 3
To start, you need to designate whether this SNR
Vote Group is to be a Main Voter/Comparator or
a Sub-comparator. A Sub-comparator feeds into
the Main Voter/Comparator and allows voting to
extend past the 8 port limit of an M4x Blade.
Any transmission path (i.e., a console, a repeater,
or a transmitter MUST reside on the Main
Voter/Comparator. A Sub-comparator can only
be used to vote receivers, and cannot have
console, repeater, or transmitter connections.
Choose the Voter Type and click “Next” to
continue.
STEP 4
Some vote
groups have a
console
connection.
If you need
voted audio
to be sent to
a console,
drag and drop
your console
port into the
Console
Connections
form.

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STEP 5
A console can be assigned “console priority”,
if necessary. When enabled, the console
priority feature gives priority to any audio
coming from the console (over any audio
coming from a voted receiver). To assign
priority to a console, check the “Priority”
check box. Click the “Delete” button to
remove a port from the list of consoles.
STEP 6
Drag and drop
any port
connections
that you want
voted into the
Vote/Receiver
form.