Full Text Searchable PDF User Manual
Food Services Trade Department
Printed
in
U.S.A
3M Center
3M 2003 March
St.
Paul,
MN
55144-1000
70-0710-3745-4
WIRELESS INTERCOM
SYSTEM
Service Information
C1060 Headset
C960
Wireless Intercom System
Table of Contents
3M 2003 March
i
Section 1. Operation and Diagrams
Introduction ..................................................................................................................................................... 1-1
System Components........................................................................................................................................ 1-1
Base Station........................................................................................................................................ 1-1
Headset ............................................................................................................................................... 1-1
Battery Charger .................................................................................................................................. 1-1
Speaker and Microphone Assemblies ................................................................................................ 1-1
Interconnect Module .......................................................................................................................... 1-1
Cross-Lane Module ............................................................................................................................ 1-1
Vehicle Alert System ......................................................................................................................... 1-1
System Configurations .................................................................................................................................... 1-1
Single-Lane Standard Communication System..................................................................................
1-1
Dual-Lane Standard Communication System ....................................................................................
1-1
Single-Lane Duplex Communication System ....................................................................................
1-2
Dual-Lane Duplex Communication System.......................................................................................
1-2
Cross-Lane Communication System .................................................................................................. 1-2
Operating Theory ............................................................................................................................................ 1-2
Processing Vehicle Alert Signals ....................................................................................................... 1-2
Transmitting and Receiving ............................................................................................................... 1-2
Talk/Listen Communication............................................................................................................... 1-3
Talk Lock Mode ................................................................................................................................. 1-3
Page Mode.......................................................................................................................................... 1-3
Page Monitor Mode............................................................................................................................ 1-4
Cross-Lane Talk/Listen Mode............................................................................................................ 1-4
Monitor Amplifier and Speaker ......................................................................................................... 1-4
Headset Components....................................................................................................................................... 1-4
Rechargeable Battery ......................................................................................................................... 1-4
Base Station..................................................................................................................................................... 1-5
DC Power ........................................................................................................................................... 1-5
Talk/Page Input .................................................................................................................................. 1-5
Vehicle Detector Input ....................................................................................................................... 1-5
Menu Mic Input.................................................................................................................................. 1-6
Base Station Configuration Jumpers and Switches............................................................................
1-6
Base Station and External Components Diagram ........................................................................................... 1-9
Interconnect Module ....................................................................................................................................... 1-11
On/Off DC.......................................................................................................................................... 1-11
Menu Microphone Signal Control...................................................................................................... 1-11
Menu Speaker Audio Control ............................................................................................................ 1-11
Monitor Speaker Audio Control......................................................................................................... 1-11
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Vehicle Detector Signal DC ............................................................................................................... 1-11
Interconnect Module Diagram......................................................................................................................... 1-13
Section 2. Installation Instructions
C860/C960 Installation Instructions
C1060 Installation Instructions
Section 3. Replacement Parts and Service
Technical Service
Base Station Assembly and Interconnect Module
C860/C960 - 3-Slot Battery Charger Assembly
C860/C960 - 6-Slot Battery Charger Assembly
C860 Replacement Parts and Service.............................................................................................................. 3-1
C960 Replacement Parts and Service
Headset Assembly .............................................................................................................................. 3-3
Replacing the Headset Speaker .......................................................................................................... 3-5
Replacing the Mic Boom Assembly................................................................................................... 3-8
Replacing the Battery Release Button Spring .................................................................................... 3-9
C1025 Replacement Parts and Service............................................................................................................ 3-11
Section 4. Operating Instructions
Model C860 Operating Instructions
Model C960 Operating Instructions
Model C1025 Operating Instructions
Model C1060 Operating Instructions
Section 5. Installation Instructions for Accessory Equipment
Model A121 Noise Reduction Module, External, 78-9236-6403-7
Model A125 Noise Reduction Module, Internal, 78-9236-6453-2
Models A200 and A201 Loop Detector
Model A300 Audio Greeter
Model A300 Operating Instructions
Model A300 Wall Placard
5-Inch Duplex Speaker Assembly, 78-6911-4411-3
Automatic Level Control Module, 78-6911-4402-2
Cross-Lane Module, 78-6911-4396-6
Duplex Menu Cable, 78-8095-0180-8
Five Inch Speaker and Mic Assembly, 78-6911-1545-1
Microphone, Duplex System With Bracket, 78-6911-4400-6
Microphone Duplex System With Foam Housing, 78-6911-4476-6
Signal Enhancer, 78-9236-6517-4
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Introduction
The 3M Wireless Intercom System is designed for
high reliability, compactness, and ease of service. It
is designed to provide two-way, radio-frequency audio
communication in quick service drive-through
restaurants and convenience stores.
The system can be programmed to operate on any one
of 16 different channels to provide high-quality audio
performance and reduce the possibility of interference
between neighboring wireless systems.
System Components
The number of components in a system varies
depending on the system configuration. However, the
base station, headset, and battery charger are common
to all system configurations.
Base Station
The wall-mounted base station contains logic and
analog circuits and related system controls, a receiver
to receive signals transmitted
from
the headsets, and a
transmitter to transmit signals
to
the headsets.
Headset
The headset is a wireless, battery-powered, two-way
radio used by the operator to communicate with menu
sign customers and with other store personnel who are
wearing headsets. The microphone and earpiece
enable the operator to transmit and receive spoken
communication and alert tones.
Some models of the headset assembly have
field-replaceable components. These components are
detailed in Section 3 of this manual (Replacement
Parts and Service).
Battery Charger
The battery charger charges headset batteries in
approximately 1.5 to 3 hours. The charger is
available in 3-slot and 6-slot versions.
The battery charger has no field-replaceable
components other than the power supply.
Speaker and Microphone Assemblies
Standard (Non--Duplex) Systems
The 5-Inch Speaker and Mic Assembly is
recommended for use in standard communication
systems. It consists of a 5-inch, weather-resistant,
eight-ohm cone speaker plus a special
weather-resistant dynamic microphone. It also
includes a mounting bracket for easy mounting in
menu signs, speaker posts and other applications.
Using this separate speaker and microphone ensures
maximum sound quality.
Duplex Systems
The 3.5-Inch Duplex Microphone and 5-Inch Duplex
Speaker Assembly are recommended for use in duplex
communication systems. The microphone is mounted
on a foam housing, which can be cut to the required
size. The speaker is mounted in a metal housing.
Interconnect Module
This optional module provides a convenient
connection point for equipment such as speakers,
microphones, vehicle detectors, and auxiliary
intercoms.
Cross-Lane Module
This module is a required component for dual-lane
duplex cross-lane communication systems. It enables
a single headset to operate two base stations.
Vehicle Alert System
The Wireless Intercom System is compatible with all
3M vehicle detectors and those of most other
manufacturers.
System Configurations
The system can be configured in one of five ways
depending on the number of menu signs at the facility
and the type of communication desired.
Single-Lane Standard Communication System
This system provides standard communication
(talk/listen) for facilities that have one menu sign. It
consists of one base station and one or more headsets
and battery chargers.
Dual-Lane Standard Communication System
This system provides standard communication
(talk/listen) for facilities that have two menu signs. It
consists of two independent systems -- one dedicated
to menu sign 1 and the other dedicated to menu sign
2. The headsets are programmed to work with one
system or the other and are labeled accordingly (1 or
2).
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Single-Lane Duplex Communication System
This system provides duplex communication
(simultaneous talk/listen) for facilities that have one
menu sign. It consists of one base station and one or
more headsets and battery chargers.
Dual-Lane Duplex Communication System
This system provides duplex communication
(simultaneous talk/listen) for facilities that have two
menu signs. It consists of two base stations and two
or more headsets and battery chargers.
Cross-Lane Communication System
This system provides duplex communication
(simultaneous talk/listen) for facilities that have two
menu signs. It consists of two duplex systems that are
connected to a cross-lane module. The headsets are
programmed for both lane 1 and lane 2.
During off-peak hours, the cross-lane module is
turned on to link the two systems and enable one
operator to talk to customers at menu sign 1 or menu
sign 2 or with other headset operators.
During peak hours, the cross-lane module is turned off
to separate the systems. With the cross-lane module
off, one system is dedicated to menu sign 1 and the
other to menu sign 2. Menu sign 1 operators can talk
to customers at menu sign 1 or with other headset
operators. Menu sign 2 operators can talk to
customers at menu sign 2 or with other headset
operators.
Operating Theory
The 3M Wireless Intercom System has two basic
functions. First, it processes vehicle alert signals that
are supplied by a hard-wired vehicle detection system.
Second, it transmits and receives radio signals to
provide the following communication:
S
Talk/listen communication
S
Page communication
Processing Vehicle Alert Signals
The vehicle alert system provides a signal to the base
station to indicate a customer is present at the menu
sign.
There are two types of vehicle detectors.
Presence
detectors
(such as magnetic loops) provide a signal
for as long as a vehicle is present at the detector.
Pulse detectors
, such as air hoses, provide only a
momentary signal—signalling vehicle arrival with no
indication of whether or not the vehicle remains at the
detector station.
S
If a presence detector is used, menu sign audio is
turned off automatically when the vehicle leaves.
S
If a pulse detector is used, menu sign audio is
silenced by pressing and releasing a headset page
switch.
When a vehicle detection signal is presented to the
base station, the base station broadcasts a repeating
alert tone to all headsets. The alert tone continues
until the talk switch [on an active headset] is pressed.
Transmitting and Receiving
The transmitting and receiving functions are
accomplished by two separate sets of radio
transmitters and receivers. One set is located in the
headset and the other in the base station.
The headset receives microphone audio signals from
the base station on
frequency B
and transmits both
audio signals and control tones on
frequency A
. The
control tones are above the audible range, and
function to turn the menu sign speaker’s amplifier ON
during the talk operation. The base station receiver is
also always ON when the base station is powered.
Similarly, when the headset is powered, the headset
receiver is always ON to enable the listen mode. The
headset modulator turns ON only when a talk or page
switch is pressed.
The transmitter in the base station is always
transmitting a “no signal” transmitter carrier, even
when there is no microphone audio from the menu
sign or headset operator being broadcast. This “no
signal“ carrier is continually broadcast to and received
by all headset receivers. It serves to block out other
radio-frequency signals or noises from headset
receivers.
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In standard communication systems, the output from
the headset receiver is muted when the headset
transmitter is ON. This provides standard
(non--duplex) communication (talk
or
listen).
In duplex communication systems, the output from
the headset receiver is enabled (not muted) when the
headset transmitter is ON. This provides duplex
communication (
simultaneous
talk
and
listen).
The two sets of transmitters and receivers work
together to provide audio communication between the
customer at the menu sign and the headset operators
inside the drive-through restaurant
or
between two or
more headset operators.
All audio transmitted by a headset during talk
operation is heard by:
S
Menu sign customers.
S
Personnel wearing active headsets.
S
People near the optional monitor speaker.
All audio from the menu sign is heard by:
S
Personnel wearing headsets that are operating in
the talk/listen mode.
S
People near the optional monitor speaker.
Talk/Listen Communication
Headset to Menu Sign
After the vehicle detection signal is presented to the
base station, the base station broadcasts a repeating
alert tone to all active headsets.
The headset operator presses and holds the talk button
to acknowledge the customer at the menu sign and
cancel the alert tone. When the headset operator
speaks into the microphone, the headset generates a
talk control tone and adds it to the microphone audio.
The microphone audio and talk control tone are then
transmitted to the base station. The talk control tone
turns the base station amplifier ON, which drives the
menu speaker enabling the customer to hear the audio.
When the base station receives the microphone audio
signal, it re-transmits it to all headset receivers. The
same microphone audio signal is also routed to the
monitor speaker amplifier if that option has been
selected.
n
Note
The menu sign audio is not turned ON unless the
base station receives a talk control tone from the
headset. However, the the monitor amplifier is
always turned ON.
Menu Sign to Headset
When the customer at the menu sign speaks, audio is
detected by a microphone and sent through wire to the
transmitter and the monitor amplifier in the base
station.
The transmitter transmits the microphone audio to all
headset receivers. The monitor amplifier routes the
same microphone audio through wire to the optional
monitor speaker.
n
Note
Personnel wearing headsets that are set to monitor
only page communications will not hear talk
communications.
Talk Lock Mode
The talk lock mode is used to operate “hands free.” In
this mode, the headset automatically switches from
standby to talk/listen when a customer is detected at
the menu sign. The headset automatically switches
back to standby when the customer leaves the menu
sign. This mode is only available with duplex system
configurations.
Page Mode
When the headset page button is pressed, system
operation is identical to
talk
operation except for two
things:
S
The
talk control tone
is not broadcast, so the
menu sign amplifier is not turned on, muting
menu sign audio.
S
A
page control tone
is sent from the headset. The
transmitter rebroadcasts this tone to turn ON any
headsets that are in the page monitor mode. Any
audio detected by the headset microphone is
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transmitted to the base station where it is
received, transmitted to other headsets and sent to
the monitor speaker amplifier.
Page Monitor Mode
The page monitor mode allows headset operators to
hear only page communication. In the page monitor
mode, talk audio output to the headset is muted. Only
internal page communication is heard because the
headset earphone amplifier is turned ON only when it
receives a
page control tone
. Talk transmissions from
other headsets or audio from the menu sign are not
heard.
Cross-Lane Talk/Listen Mode
The cross-lane talk/listen mode is available only in a
dual-lane duplex cross-lane system. The cross-lane
module in this system enables the menu sign operator
to selectively communicate (talk and listen) to
customers in
either
lane 1
or
lane 2.
With the T1 (Talk Lane 1) switch pressed, the headset
transmitter/receiver switches to the lane 1 channel
frequencies, enabling the lane 1 base station and lane
1 communications.
With the T2 (Talk Lane 2) switch pressed, the headset
transmitter/receiver switches to the lane 2 channel
frequencies, enabling the lane 2 base station and lane
2 communications.
Monitor Amplifier and Speaker
A one-watt, single-ended monitor amplifier in the
base station powers [an optional] speaker which is
capable of reproducing the following signals:
S
Talk audio (communications
to
the menu speaker)
S
Listen audio (communication
from
the menu
speaker)
S
Page audio (internal store communications)
S
Vehicle alert tone
Separate volume controls adjust the level of each
signal to achieve the desired signal balance. In
addition, there is a master volume control which
adjusts the overall volume of the monitor speaker.
Headset Components
n
Note
The receiver/transmitter and logic circuitry
contained in the headset housing is both proprietary
and non-field repairable.
Some models of the headset assembly have several
field-replaceable components. These components are
detailed in Section 3 of this manual (Replacement
Parts and Service).
The major components are as follows:
S
Rechargeable Battery
S
Headband
S
Microphone Boom Assembly
S
Speaker Assembly
Rechargeable Battery
The nickel metal hydride or lithium--ion battery
provides DC power for the headset circuitry.
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Base Station
n
Note
Receiver/transmitter and logic circuitry contained
in the base station is both proprietary and non-field
repairable. For this reason, the accompanying base
station diagram provides no circuit component
detail. Only those details that assist fault isolation
(such as connections, configuration jumpers, audio
control circuits, replaceable components and
input/output functions) are shown.
DC Power
DC power for the base station circuits and external
components is provided as follows:
A self-contained DC power transformer, connected to
120VAC, provides unregulated +12VDC to the base
station power input jack. The +12VDC is turned on
or off by a slide switch located on the front of the base
station. The unregulated +DC is routed through a
protective polyswitch (circuit breaker) to circuit
components and a voltage regulator (called power
supply in the diagram). If an overcurrent condition
causes the polyswitch to open, it automatically resets
after power is removed.
The unregulated +12VDC is used by the vehicle
detector to provide a +DC vehicle detect signal to the
base station vehicle detect circuits. If an interconnect
module is used in the system, unregulated +DC is
provided to energize the interconnect module relays.
Talk/Page Input
Talk and page voice communications transmitted from
the headset are received along with their
accompanying “talk” or “page” control tones.
Received talk communications are routed by the
RCVR & RCVR LOGIC as follows:
S
To the menu sign speaker amplifier via the
DAY/NIGHT volume controls and DAY/NIGHT
switch, through the amplifier to the menu sign
S
To the monitor speaker amplifier via the MON
TALK volume control, through the amplifier and
the Master Monitor Volume control to the monitor
speaker
S
Through the transmit amplifier to the TXMT &
TXMT LOGIC for transmission to all headset
receivers and to output connector AUDIO OUT
for use in cross-lane applications
Received page communications are routed by the
RCVR & RCVR LOGIC as follows:
S
To the monitor speaker amplifier via the MON
PAGE volume control, through the amplifier and
the Master Monitor Volume control to the monitor
speaker
S
Through the transmit amplifier to the TXMT &
TXMT LOGIC for transmission to all headset
receivers, and to output connector AUDIO OUT
for use in cross-lane applications
Vehicle Detector Input
Upon detection of a vehicle, the vehicle detector
signal will be a steady DC or a short-duration DC
pulse depending on whether the vehicle detector is a
“presence” or “pulse” type detector. Upon receipt of
the vehicle detect signal, the VEHICLE DETECT
LOGIC circuit emits alert tones. These alert tones are
routed as follows:
S
To the monitor speaker amplifier via the MON
ALERT volume control, through the monitor
speaker amplifier and the Master Monitor volume
control to the monitor speaker
S
To the transmit amplifier via the Headset Alert
Level control, through the amplifier to the TXMT
& TXMT LOGIC for transmission to all headset
receivers
S
To output connector ALERT OUT for use in
cross-lane applications
n
Note
The vehicle detect PULSE/PRESENCE jumper J4
must be set appropriately and its setting
programmed into the base station logic for correct
vehicle detection and alert tones to occur. For
further explanation of vehicle detect alert tones,
refer to the paragraphs titled
Vehicle Alert System
and
Vehicle Detector Input
in this section.
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Menu Mic Input
Audio from the menu sign may come from one of two
sources: a combination speaker/microphone (the
MENU SIGN SPEAKER) or a separate dynamic
microphone (the MENU MIC). The MIC/SPKR
jumpers J1 and J2 must be set accordingly; both must
be set to the MIC position if a separate outside mic is
used, to the SPKR position if a combination outside
speaker/mic (OSM) is used. Depending on jumper
positions, mic input is routed to the mic amplifier,
through the amplifier and its Menu Mic Sensitivity
control and then:
S
To the monitor speaker amplifier via the MON IN
volume control, through the monitor speaker
amplifier and the Master Monitor volume control
to the monitor speaker
S
Through the transmit amplifier to the TXMT
&TXMT LOGIC for transmission to all headset
receivers, and to output connector pin 9 for use in
cross-lane applications
Base Station Configuration Jumpers and
Switches
Configuration Jumpers
Jumpers J1 and J2 are used to configure the base
station for use with either a separate outside
microphone or a combination outside speaker/mic
(OSM). Unlike jumpers J3, J4 and J5 which affect
logic input levels, jumpers J1 and J2 simply switch
the microphone amplifier inputs to either the
microphone or OSM. Set both jumpers to jumper pins
2 and 3 for use with a separate outside mic, or to
jumper pins 1 and 2 for a combination speaker/mic
(OSM).
Jumper J3 is used to configure the base station for use
in a cross-lane, dual-lane communications system. In
such a system, one base station must be set for lane 1
frequency communications, the other base station
must be set for lane 2 frequency communications.
Jumper J3 pins 1 and 2 (forcing the related logic input
high) for lane 1 configuration. Jumper J3 pins 2 and 3
(forcing the related logic input low) for lane 2
configuration. Whenever any jumper is changed, you
must press the base station RESET switch to program
the new jumper setting into the base station
microprocessor.
n
Note
It may also be necessary to re-program system
headsets, depending on system configuration.
Refer to the Installation Instructions for more
information.
Jumper J4 is used to configure the base station for use
with either a presence type vehicle detector or a pulse
type vehicle detector. Jumper J4 pins 1 and 2 (forcing
the related logic input high) for a presence type
detector. Jumper J4 pins 2 and 3 (forcing the related
logic input low) for a pulse type detector. Whenever
jumper J4 is changed, you must press the base station
RESET switch to program the new jumper setting into
the base station microprocessor.
Jumpers J5 and J6 are used to configure the base
station so that it can in turn, program the headsets for
standard (talk, then listen, then talk etc.)
communications or for duplex (simultaneous talk and
listen) communications. During standard
communications, headset receiver output is muted
during talk transmissions. During duplex
communications, headset receiver output is not muted
during talk transmissions. The headset receiver
mute/not mute (standard/duplex) command is sent to
the headset logic during headset
programming—determined by the jumper J5 setting.
Whenever any Jumper is changed, you must press the
base station RESET switch to program the new
jumper setting into the base station microprocessor.
n
Note
When any jumper is changed, you must also
reprogram the system headsets. Refer to the
Installation Instructions for more information.
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Configuration Switches
RESET SWITCH: Very briefly, actuation of the
RESET SWITCH clears logic inputs of their
established levels and latches the logic inputs at their
new levels.
CHANNEL SELECT SWITCH: The Wireless
Intercom System is capable of operating on eight
different channels for each of two lanes. This
provides a total of 16 operating channels since each
system may be designated as a lane 1 or lane 2
system. Each operating channel is comprised of a
“set” of two frequencies, one for receiving, one for
transmitting. The channel frequencies are
preprogrammed in both the base station and headset
microprocessors. Each actuation of the CHANNEL
SELECT switch prompts the base station
microprocessor to advance to the next available
channel. After a new channel is selected, you must
reprogram all system headsets to the new channel.
For more information on channel selection and
reprogrammning, refer to the Installation Instructions.
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Interconnect Module
An interconnect module is needed when a Headset
Intercom System includes an auxiliary intercom to
provide continued communications when the primary
intercom needs service.
The auxiliary intercom may be a conventional,
hard-wired intercom or it may be a second base
station.
External system components (speakers, microphone,
vehicle detector) connect to interconnect module
connector J302. Base station inputs and outputs
(power, common, menu mic, menu speaker, vehicle
detector) connect to interconnect module connector
J303. Auxiliary intercom (or second base station)
inputs and outputs connect to interconnect module
connector J301.
On/Off DC
In the interconnect module schematic diagram, the
interconnect module is shown in its “off” state, with
relays de--energized.
On/Off control of the interconnect module is provided
by (the presence or absence of) +12VDC from the
(primary) base station. With base station +12VDC
present (via J303 pins 1 and 2), relays K301, K302
and K303 energize to switch microphone, speaker and
vehicle detect signals to/from the base station. If the
base station-provided DC is not present (base station
turned off), relays K301, K302 and K303 de-energize
to switch the same signals to/from the auxiliary
intercom.
Menu Microphone Signal Control
Relay contacts K301-A and K301-B control
distribution of the menu mic signal(s). With relay
K301 energized, the menu mic is connected to the
base station inputs. With Relay K301 de-energized,
the menu mic is connected to the auxiliary intercom.
Menu Speaker Audio Control
Relay contacts K302-A and K302-B control
distribution of the menu speaker audio. With relay
K302 energized, the menu speaker is connected to the
base station. With relay K302 de-energized, the menu
speaker is connected to the auxiliary intercom.
Monitor Speaker Audio Control
Relay contacts K303-B control distribution of monitor
speaker audio. With relay K303 energized, the drive
side of the monitor speaker is connected to the
monitor speaker output of the base station. With relay
K303 de-energized, the drive side of the monitor
speaker is connected to the monitor speaker output of
the auxiliary intercom. Monitor speaker common is
not switched.
Vehicle Detector Signal DC
While the vehicle detector is powered separately (if it
is a “presence” type detector), vehicle detector signal
DC is always provided by both the base station and
the auxiliary intercom. This vehicle detector signal
DC is available at interconnect module connector
J302-9.
A vehicle detector signal DC of +12VDC is provided
by the base station at J303 pins 9 and 10. A vehicle
detector signal DC of +18VDC is provided by the
auxiliary intercom at J301 pins 1 and 7.
If both the auxiliary intercom and the base station are
ON, the vehicle detector signal will always be
+18VDC because the auxiliary intercom’s +18VDC
will take precedence over the +12VDC supplied by
the base station. (Isolation of the two DC sources is
provided by interconnect module diodes D301 and
D303.) If only the base station is ON, the vehicle
detector signal DC will be +12VDC.
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