Clear-Com KB-702GM User Manual

CLEAR-COM ENCORE

KB-702/KB-702GM TWO-CHANNNEL

SPEAKER STATIONS

INSTRUCTION MANUAL

KB-702/KB-702GM Two-Channel Speaker Stations Instruction Manual

Part Number: 810492Z Rev. 3

Legal Disclaimer

Copyright © 2013 HME Clear-Com Ltd.

All Rights Reserved

Clear-Com, the Clear-Com logo, and Clear-Com Concert are trademarks or registered trademarks of HM Electronics, Inc.
The software described in this document is furnished under a license agreement and may be used only in accordance with the
terms of the agreement.

The product described in this document is distributed under licenses restricting its use, copying, distribution, and decompilation/
reverse engineering. No part of this document may be reproduced in any form by any means without prior written authorization
of Clear-Com, an HME Company.

Clear-Com Offices are located in California, USA; Cambridge, UK; Montreal, Canada; and Beijing, China. Specific addresses
and contact information can be found on Clear-Com's corporate website:

www.clearcom.com

Clear-Com Contacts

Americas and Asia-Pacific Headquarters

California, United States
Tel: [phone]
Email: [e-mail]

Europe, Middle East, and Africa Headquarters

Cambridge, United Kingdom
Tel: [phone]
Email: [e-mail]

Canada Office

Quebec , Canada
Tel: [phone]

China Office

Beijing Representative Office
Beijing, P.R.China
Tel: [phone]

CONTENTS

OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Internal Adjustments and Connections . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5

INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Block Diagram for the KB-702 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Block Diagram for the KB-702GM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

TECHNICAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . 4-1

KB-702/KB-702GM Two-Channel Speaker Stations . . . . . . . . . . . . . . . . . 4-1

LIMITED WARRANTY. . . . . . . . . . . . . . . . . . . . . . . . . . 5-I

Warranty Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-i

Technical Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-i

Warranty Repairs and Returns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-ii

Non-Warranty Repairs and Returns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-ii

Extended Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-ii

Service Contract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-iii

Liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-iii

KB-702/KB-702GM TWO-CHANNEL

i

ii

KB-702/KB-702GM TWO-CHANNEL SPEAKER

Please read and follow

these instructions before

operating this product.

IMPORTANT SAFETY INSTRUCTIONS

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not use this apparatus near water.

6. Clean only with dry cloth.

7. Do not block any ventilation openings. Install in accordance with the
manufacturer’s instructions.

8. Do not install near any heat sources such as radiators, heat registers,
stoves, or other apparatus (including amplifiers) that produce heat.

9. Only use attachments/accessories specified by the manufacturer.

10. Use only with the cart, stand, tripod, bracket, or table specified by the
manufacturer, or sold with the apparatus. When a cart is used, use caution
when moving the cart/apparatus combination to avoid injury from
tip-over.

11. Unplug this apparatus during lightning storms or when unused for long
periods of time.

12. Refer all servicing to qualified service personnel. Servicing is required
when the apparatus has been damaged in any way, such as power-supply
cord or plug is damaged, liquid has been spilled or objects have fallen into
the apparatus, the apparatus has been exposed to rain or moisture, does
not operate normally, or has been dropped.

13. WARNING: To reduce the risk of fire or electric shock, do not expose
this product to rain or moisture.

Please familiarize yourself with the safety symbols in Figure 1. When you
see these symbols on this product, they warn you of the potential danger
of electric shock if the station is used improperly. They also refer you to
important operating and maintenance instructions in the manual.

KB-702/KB-702GM TWO-CHANNEL

iii

CAUTION

RISK OF ELECTRIC SHOCK

DO NOT OPEN

This symbol alerts you to the presence of uninsulated dangerous
voltage within the product's enclosure that might be of sufficient
magnitude to constitute a risk of electric shock. Do not open
the product's case.

This symbol informs you that important operating and main­tenance instructions are included in the literature accompanying
this product.

Figure 1: Safety Symbols

EMC AND SAFETY

The KB-702 and KB-702GM stations meet all relevant CE and FCC
specifications set out below:

EN55103-1 Electromagnetic compatibility. Product family standard for
audio, video, audio-visual, and entertainment lighting control apparatus
for professional use. Part 1: Emissions.

EN55103-2 Electromagnetic compatibility. Product family standard for
audio, video, audio-visual, and entertainment lighting control apparatus
for professional use. Part 2: Immunity.

And thereby compliance with the requirement of Electromagnetic
Compatibility Directive 2004/108/EC and Low Voltage Directive
2006/95/EC

This device complies with Part 15 of the FCC Rules. Operation is subject
to the following two conditions: (1) this device may not cause harmful
interference, and (2) this device must accept any interference received,
including interference that may cause undesired operation.

iv

KB-702/KB-702GM TWO-CHANNEL SPEAKER

OPERATION

INTRODUCTION

Congratulations and thank you for choosing this Clear-Com product. The
KB-702 and KB-702GM two-channel speaker stations are powerful,
user-friendly units that can serve as versatile intercom stations.

Please read this manual completely to better understand the functions of these
products. For questions not addressed in this manual, contact the dealer or
Clear-Com directly. Clear-Com applications support and service people are
ready to help.

DESCRIPTION

The Clear-Com KB-702 is a two-channel speaker station ideal for theatre, live
performances, industrial applications, and small TV facilities. It features
excellent speech intelligibility even in high-noise environments and can be
tailored to your needs through its programmable options.

In addition, the Clear-Com KB-702GM contains a jack for an optional
Clear-Com gooseneck panel microphone and a close-in, voice-controlled
circuit (VOX). This circuit allows automatic, alternate dipping of the panel
microphone and the speaker in response to conversation.

Selectable two-channel talking and/or listening allows the operator to
communicate on either of the intercom channels. The dual-action talk button
is electronic momentary or latching. Monitoring can be done through the
headset, the integral speaker, or both at once. The KB-702 offers both visual
and audible call signaling to attract the attention of operators. The remote mic
kill (RMK) feature on main stations will turn off any open mics on the
KB-702.

A balanced program input allows the monitoring of external audio using the
headset or speaker. This program input can also be used as a paging function.

The KB-702 speaker station accepts dynamic headsets. A sidetone control
allows the operator to vary the level of his/her own voice as heard in the
headset and speaker.

The integral speaker can be turned on or off by a convenient front panel
switch. An automatic speaker dipping circuit will lower the level of the
speaker whenever the talk button is activated. This feature helps minimize
acoustical feedback.

The KB-702 receives power from the Clear-Com intercom line. The unit
mounts either in a standard four-gang electrical outlet box or in an optional
Clear-Com four-gang V-box. The extra-thick front panel and compact
surface-mount circuitry maintains legendary Clear-Com ruggedness. The two
intercom channels connect to a plug-on screw terminal strip. Male and female

KB-702/KB-702GM TWO-CHANNEL

1-1

3-pin XLR connectors are provided on the four-gang V-box for an inline

Speaker

Program Level

Off On

A

B

Channel Select

KB-702KB-702

Call

Talk

Sidetone

Headset

Volume

2-Channel
Speaker Station

3

4

9

2

1

5

7610

connection to one of the intercom channels.

The optional EB7-TW daughter board module can be installed to provide an
interface to two intercom channels on a single microphone cable. Also, the
EB7-4W four-wire daughter board module is available to allow long-distance
connections using separate pairs of wire for send audio and receive audio. The
EB7-4W four-wire option supports two-channel operation.

The KB-702 and KB-702GM are compatible with all Clear-Com party-line
intercoms.

OPERATION

Normal operation of the KB-702 speaker station requires access only to the
front panel controls. The controls located elsewhere on the unit are intended
to be set-and-forget in nature. For intercom operation, set the listen level
control to the desired level and press the talk button when talking. If a headset
or handset is used, set the sidetone control for each channel for the desired
amount of sidetone in the earphone. If a hand-held push-to-talk mic is used, or
if the panel mic is used on the KB-702GM, set the sidetone controls for
minimum feed-through to the speaker to prevent acoustic feedback.

FRONT PANEL

The controls, indicators, and connectors found on the KB-702 and
KB-702GM front panels are shown in the following figures and are described
by the following text. The numbers in the left column refer to Figure 1-1 and
Figure 1-2.

1-2

KB-702/KB-702GM TWO-CHANNEL SPEAKER

Figure 1-1: KB-702 Front Panel

1. Talk Button and Indicator: The talk button activates the microphone

Speaker

Program Level

Off On

A

B

Channel Select

KB-702GMKB-702GM

Call

Talk

Sidetone

Headset

Panel Mic

VOX

Headset

Volume

Microphone

2-Channel
Speaker Station

6

7

3

4

9

2

8

1211

10

5

1

feed to the selected intercom channel. It has a dual action (momentary or
latching) depending upon how the button is pressed. If desired, the
latching function can be defeated using an internal option switch. The

following describes the various functions of this button.

• MOMENTARY: Press and hold the talk button while you are

speaking. Release it when you are finished. The button lights amber
when the talk function is active and blue when it is inactive.

• LATCHING: Press the button quickly to latch the talk function. Press

the button again to turn off the talk function.

• VOX INDICATION: On the KB-702GM, when the VOX feature is

enabled, the talk button illuminates amber to indicate an active talk,
and the VOX light illuminates amber to indicate that the panel
microphone is in use. This will automatically dip the speaker.

2. Call Button and Light: Pressing the call button will send a call signal on
the selected channel. All the call lights on that channel will then flash.
Call signals can also be sent while talking if required. The call button will
light when pressed, or whenever a call signal is present on the selected
channel. An internal option jumper can be set to allow the call button to
light when a call signal is present on either channel.

3. Tone Alert: An audible tone alert can be enabled to sound when a call
signal is received on the selected channel or either channel. This can be
useful when the operator’s attention has been drawn away from the
KB-702 indicator panel. The audible tone alert level can be adjusted or
turned off by an internal control. The tone alert will not sound if a call

KB-702/KB-702GM TWO-CHANNEL

Figure 1-2: KB-702GM Front Panel

1-3

signal originates at the KB-702 station or if the speaker on/off switch is
turned off. The tone alert plays through both the speaker and headset if the
speaker on/off switch is turned on.

4. Volume Control: Turn this control to set the volume required on the speaker or headset. This control does not affect the tone alert level or the program input level.

5. Sidetone Control: Sidetone is the level of your own voice that you hear
while talking on the intercom. Setting a comfortable level of sidetone will
ensure that the intercom line sounds alive and also helps you modulate
your voice relative to other voices on the line.

Typically, different sidetone null settings are needed depending upon
whether you are using the speaker. Use one of the following procedures
to correctly set the sidetone level control.

Sidetone Adjustment Procedure for Headset:

1. Set the intercom level control to a comfortable level by having

someone talk to you from another station.

2. Press the talk button and speak into the microphone while turning the

sidetone null control slowly back and forth until you hear your voice
at a comfortable level in the headset.

Sidetone Adjustment Procedure for Gooseneck Mic (KB-702GM only) or
hand-held push-to-talk mic with the speaker turned on:

1. Set the VOX control fully counterclockwise to disable this feature.

2. Set the intercom level control to a comfortable level.

3. Press the talk button and speak into the microphone while turning the

sidetone null control slowly back and forth. There should be a point
where your voice (and any accompanying acoustic feedback)
disappears. This is the null point.

4. Readjust the VOX control. (Refer to the VOX control paragraph in

this section.)

6. Program Level Control: Adjust the program level control to set the program audio level heard in the headset or panel speaker.

Note: Do not force the trimpots past their stop points. This will damage

them.

7. Speaker On/Off Switch: The speaker on/off switch turns the front panel
speaker on or off. This switch also controls whether the tone alert is heard
through the speaker. The speaker volume will automatically dip whenever
the talk function is set, unless the VOX function is disabled.

8. Mic Select Switch (KB-702GM only): The mic select switch selects whether the panel microphone or the headset microphone is active. If the VOX feature is enabled, it is only operational when the panel microphone is active.

9. Channel Switch: This switch selects whether the speaker station is active on intercom channel A or channel B.

10. Headset Connector: The headset connector is located on the front panel.
All Clear-Com headsets are recommended for use with the KB-702. The
Clear-Com handheld push-to-talk microphone will also plug into the

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KB-702/KB-702GM TWO-CHANNEL SPEAKER