Clear-Com KB-702 Datasheet

The KB-702 remote speaker station permits the user to select
between two channels of party-line communications, with the ability
to talk and/or listen on the selected channel. The user can listen via
the integral speaker, or may use a headset or telephone-style handset

- and can talk via a headset mic, a telephone handset, or a push-to­talk microphone.

The KB-702GM adds a gooseneck-mic connector and VOX circuitry,
for hands-free full-duplex communications without a headset.

A switch allows the user to choose between the optional GM-9 or
GM-18 microphone and the headset connector. The adjustable­sensitivity, close-in VOX feature automatically detects the user’s voice
at the mic and dips the level of the integral speaker while increasing
the gain of the microphone, performing in the opposite manner when
listening. The potential for acoustic feedback is minimized while
permitting natural conversation levels and dynamics.

Microprocessor-controlled logic and switching yields a feature-rich
intercom station in a compact format. Electronic switching for the
talk button, blue-color LED (on), amber color LED (off), permits
momentary or latching operation. For call signaling, a bright LED
lights when a call is activated on a connected intercom channel.
A defeatable audible call signal, with level control, is also provided.
Separate level controls are provided for intercom level and for
balanced program input. A local program source may be fed to the
station, allowing the user to monitor that source while remaining in
contact on the intercom system. The balanced program input can
also be used in conjunction with the stage-announce output of a main
station to provide a paging interrupt, allowing paging at the KB station
even if the intercom volume control is turned down.

A set of option dip switches is located at the top of the circuit board.
Switches are provided for mic-latch disable (momentary-only talk),
long-line operation, channel selection, call signal tracking, and audible
call signaling.

These versatile stations may be wall or
console mounted in a standard U.S. 4-gang
electrical box, or may be mounted in the
optional V-Box for desktop, surface-mount,
or portable applications.

Either of the stations may be used with the
optional 4-wire or TW (two channels on a
single mic cable) daughter boards. On the
TW board, the stations become plug in
compatible with a Clear Com TW system.
The 4-wire board creates separate send and
receive circuits, so that the station may be
attached to fiber-optic lines or other audio
routing systems with 4-wire connections.
The stations are powered by the intercom
line or by a local power supply when used
with the optional 4-wire daughter board.

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Features:

• Selectable two-channel, full-duplex
operation

• Microprocessor-controlled logic and
switching

• Momentary/latching talk button

• Visual and audible call signaling,
with bright LED indicator

• Balanced local program input with
separate level control

• Internal controls for call signal tracking,
mic latch disable, and other functions

• Use with headset or handset, with
integral speaker for monitoring

• KB-702GM adds mic jack for goose­neck mic plus VOX circuitry

• Optional TW and 4-Wire daughter
boards provided additional flexibility

• Wall or console mount, or optional
V-Box for portable or desktop use

• LED buttons for talk, listen, call,
announce, link, all talk, or mic on.

Clear-Com Encore

TM

KB-702, KB-702GM, KB-701 Remote Speaker Stations

KB-702

The KB-701 remote speaker station connects to a single channel
of party-line intercom, and operates in half-duplex mode, similar
to a walkie-talkie. It features both an integral speaker and a flush­mount electret microphone with mic limiter and a push-to-talk
button. The station may be programmed via two internal dip
switches to operate in four different modes, activated by other
stations within the intercom system. The different operating
modes are activated using the call signaling function of another
station, which allows for individual control of the speaker and
microphone.

Microprocessor-controlled logic and switching yields a feature­rich intercom station in a compact format. An electronic
momentary-only talk button activates the talk function. Use
the talk button or the reomote control from another station to
activate the mic. A blue-colour LED indicates that the mic is
on, while an amber-color LED indicates the mic is off. Mic
sensitivity is selectable for either close or distant voice pickup.

The KB-701 offers both visual and audible call signaling, gaining
the attention of the user when not at the station. A red-color
LED lights when a call is activated on a connected intercom
channel. A defeatable audible call signal, with level control, is
also provided. Separate level controls are provided for intercom
level and for balanced program input. A local program source
may be fed to the station, allowing the user to monitor that
source while remaining in contact on the intercom system.
The balanced program input can also be used in conjunction with
the stage-announce output of a main station to provide a paging
interrupt. This would allow paging at the station even if the
intercom volume control is turned down. In addition, the
intercom volume control of the KB-701 can be internally set so
that an incoming message would still be audible, even if the
control was turned all the way down.

The KB-701 may be wall or console
mounted in a standard 4-gang electrical
box, or may be mounted in the optional
V-Box for desktop, surface-mount, or
portable applications. It may be used with
the optional 4-wire or TW (two channels
on a single mic cable) daughter boards.
The station is powered by the intercom
line or by a local power supply when used
with the optional 4-Wire daughter board.

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Features:

• Single-channel, push-to-talk speaker
station

• Four different modes of operation,
internally programmable

• Microprocessor- controlled logic
and switching

• Flush-mounted internal microphone

• Visual and audible call signaling, with
bright LED indicator

• Balanced local program input with
separate level control

• Optional TW and 4-Wire daughter
boards provide additional flexibility

• Wall or console mount, or optional
V-Box for portable or desktop use

• LED buttons for talk, listen, call,
announce, link, all talk, or mic on.

Clear-Com Encore

TM

KB-701 Single-Channel Speaker Station

KB-701

www.clearcom.com

Clear-Com Encore

TM

KB-702, KB-702GM, KB-701 Remote Speaker Stations

Accessories

4-wire Option Module

The 4-wire option module plugs into pins
on the KB- 702, KB- 702GM, and KB-701
speaker stations. It consists of the necessary
circuitry and connectors to convert any of
these stations to 4-wire operation, and can
accept two 4-wire connections. This option
allows the speaker station to be used at
much longer distances than are possible
with a standard two-wire intercom line, and
also permits the station to operate via fiber
optic cable and other devices with 4-wire
connections. The module provides a
transformer- isolated audio connection,
and does not transfer the call signal.
A station using this option module must
be locally powered.

TW Option Module

The option module plugs into pins on the
KB-702, KB-702GM, and KB-701 speaker
stations. This option allows the station to
send and receive two channels of audio on
a single 3-pin micro-phone cable. With the
TW module in place, the station can become
a part of a Clear-Com TW system, and is
compatible with TW beltpacks and other
components.

V-Box Desktop/Wall-Mount
Enclosure

The V-Box converts any of the KB speaker
stations into a desktop, portable, or wall­mount unit. The station panel may be
secured with four screws in one of the two
mounting spaces, for either an angled or a
vertical panel orientation. A blank plate with
mounting keyholes is provided to cover the
second mounting space. 3-pin XLR male
and female connectors are mounted on the
side panel, wired to a connector block for
easy connection to the speaker station.
The rugged metal and stained-wood
enclosure is both durable and attractive
for long-term professional use.

Dimensional Drawings

KB-702 in a V-Box

4.50

3.25

(114)

(83)

5.4

(137)

8.25

(210)

KB-211 Rear View

2.85
(72)

8.27
(211)

V-Box Front View

1.25 *
(32)

* 1.75" for
KB-702GM
or with

8.25

option

(210)

modules

.5

(13)

KB-702 Sideview

.5

(13)

6.04
(153)

5.56
(141)

V-Box Side View

www.clearcom.com

Americas & Asia 850 Marina Village Parkway, Alameda, CA 94501 USA Tel: [phone]
Europe, Middle East & Africa 7400 Beach Drive, Cambridge Research Park, Cambridge, UK Tel: [phone]

© 2007, Vitec Group Communications, LLC. All rights reserved. ® Clear-Com is a registered trade mark of The Vitec Group plc.

Clear-Com Encore

TM

KB-702, KB-702GM, KB-701 Remote Speaker Stations

dBu is an absolute measurement. 0 dBu is
referenced to 0.775 volts RMS

Panel Microphone Input (KB-702GM)

Input Type: Electret
Input Impedance: >=2KΩ
Mic Limiter Threshold: -2dBu ±3dB
Mic Limiter Range: >= 15dB

Headset Microphone Input

Input Type: Dynamic
Input Impedance: >= 1KΩ
Mic Limiter Threshold: -2dBu ± 3dB
Mic Limiter Range: >= 15dB

Program Line Input

Maximum Level before
Clipping: >= 20dBu
Input Impedance: >= 5KΩ

Headset Output

Load Impedance: >= 8Ω
Output Impedance: <= 25Ω
Output Limiter Threshold: +5dBu ± 3dB
Maximum Output Level
before Distortion: >= 17dBu

Speaker Output

Load Impedance: >= 4Ω
Max Output Level before
1% Distortion: 20dBu ± 2dBu

Party Line Output

Off Noise: < -74dBu
Output Impedance: >10KΩ

Party Line Input

Crosstalk: < -60dB
Max level before Clipping : >= 12dBu
Sidetone Null Capability
(KB-702GM only): > 25dB

Frequency Response

Panel Mic - Party Line
(KB-702GM only): 300 - 16KHz ± 3dB
Headset Mic - Party Line: 300 - 15KHz ± 3dB
Program Input - Headset Out: 200 - 18KHz ± 3dB
Program Input - Speaker Out: 200 - 18KHz ± 3dB
Party Line - Headset Out: 200 - 18KHz ± 3dB
Party Line - Speaker Out: 200 - 18KHz ± 3dB

Max Distortion

Panel Mic - Party Line
(KB-702GM only): <= 0.5%
Headset Mic - Party Line: <= 0.5%
Program Input - Headset Out: <= 0.2%
Program Input - Speaker Out: <= 0.5%
Party Line - Headset Out: <= 0.2%
Party Line - Speaker Out: <= 0.5%

Noise

Panel Mic - Party Line
(KB-702GM only): < -65dBu
Headset Mic - Party Line: < -70dBu
Program Input - Headset Out: < -60dBu
Program Input - Speaker Out: < -60dBu
Party Line - Headset Out: < -50dBu
Party Line - Speaker Out: < -50dBu

Max Gain

Panel Mic - Party Line
(KB-702GM only): >= 37dB
Headset Mic - Party Line: 41dB ± 2dB
Program Input - Headset Out: >= 18dB
Program Input - Speaker Out: >= 24dB
Party Line - Headset Out: >= 34dB
Party Line - Speaker Out: >= 40dB

Power

Input Voltage Range: 20-30 VDC
Input Current (Idle): <= 90mA
Input Current (Max): <=110mA

Internal Adjustments and Connections

Intercom: Line Five terminal

connector

Program Input Three terminal

connector
Option Switches: Three DIP switches
Call Signal Jumper3: Three sets of

options jumpers
Call Alert Tone Level Control: Level adjustment

control

Front Panel Connectors

Panel Mic (KB-702GM only): (1) 1/4 in. (0.64 cm)

panel mounting jack
Headset: (1) XLR-4M

Front Panel Controls & Indicators (KB-702GM)

(1) Panel /headset mic switch
(1) Program monitor level control
(1) Sidetone null control
(1) Talk button
(1) Call button
(1) Speaker ON-OFF switch
(1) Channel select switch
(1) Speaker volume control
(1) VOX control
(1) VOX indicator

Front Panel Controls & Indicators (KB-702)

(1) Program monitor level control
(1) Sidetone null control
(1) Talk button
(1) Call button
(1) Speaker ON-OFF switch
(1) Channel select switch
(1) Speaker volume control

Environmental

32 - 122˚F (0 - 50˚C)

Dimensions

8.25 in. W x 4.5 in. H x 1.75 in. D
(210 mm x 114 mm x 44 mm)

Weight

KB-702 0.99 lbs. (0.45 Kg)
KB-702GM 1.1 lbs. (0.50 Kg)

Program Line Input

Maximum Level before Clipping: >= 20dBu
Input Impedance: >= 5KΩ

Speaker Output

Load Impedance: >= 4Ω
Max Output Level before
1% Distortion: 20dBu ± 2dBu

Party Line Output

Off Noise: < -74dBu
Output Impedance: >10KΩ

Party Line Input

Crosstalk: < -60dB
Max level before Clipping: >= 12dBu

Frequency Response

Program Input - Speaker Out: 200 - 18KHz ± 3dB
Party Line - Speaker Out: 200 - 18KHz ± 3dB

Max Distortion

Program Input - Speaker Out: <= 0.5%
Party Line - Speaker Out: <= 0.5%

Noise

Program Input - Speaker Out: < -60dBu
Party Line - Speaker Out: < -50dBu

Max Gain

Program Input - Speaker Out: >= 24dB
Party Line - Speaker Out: >= 40dB

Power

Input Voltage Range: 20-30 VDC
Input Current (Idle): <= 90mA
Input Current (Max): <=110mA

Internal Connectors and Jumpers

Intercom: Line Five terminal

connector

Program Input: Three terminal

connector

Option Switches: Three DIP switches

Front Panel Controls & Indicators

(1) Program level control
(1) Intercom level control
(1) Talk button

(1) Call button
(1) Integral microphone

Environmental

32 - 122o F (0 - 50o C)

Dimensions

8.5 in. W x 4.5 in. H x 1.75 in. D
(210 mm x 114 mm x 44 mm)

Weight

1.04 lbs. (0.47 Kg)

Notice About Specifications

While Clear-Com makes every attempt to maintain the
accuracy of the information contained in its product
manuals, that information is subject to change without
notice. Performance specifications included in this manual
are design-center specifications and are included for
customer guidance and to facilitate system installation.
Actual operating performance may vary.

Technical Specifications, KB-701 Speaker Station

Technical Specifications, KB-702/KB-702GM Two-channel Speaker Stations: