Clear-Com KB-701 User manual

KB-701 SPEAKER STATION
INSTRUCTION MANUAL
CLEAR-COM ENCORE

KB-701 Speaker Station Instruction Manual
© 2007 Vitec Group Communications
All Rights Reserved
Part Number 810350Z Rev. 2
Vitec Group Communications, LLC.
850 Marina Village Parkway
Alameda, CA 94501
U.S.A
Vitec Group Communications
7400 Beach Drive
Cambridge Research Park
Cambridgeshire
United Kingdom
CB25 9TP
Vitec Group Communications
Room 1806, Hua Bin Building
No. 8 Yong An Dong Li
Jian Guo Men Wai Ave
Chao Yang District
Beijing, P.R. China 100022
Clear-Com is a registered trademark of Vitec Group Communications.
The Clear-Com Logo is a registered trademark of Vitec Group Communications.

KB-701 SPEAKER STATION i
CONTENTS
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Front Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Internal Adjustments and Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
KB-701 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Troubleshooting Tips. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
TECHNICAL SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
KB-701 Speaker Station. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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-701 SPEAKER STATION
ii

KB-701 SPEAKER STATION iii
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.
Please read and follow these
instructions before operating
this product.

KB-701 SPEAKER STATION
iv
Figure 1: Safety Symbols
EMC AND SAFETY
The KB-701 station meets 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.
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 main-
tenance instructions are included in the literature accompanying
this product.

KB-701 SPEAKER STATION 1-1
OPERATION
INTRODUCTION
Congratulations on choosing this Clear-Com product. Clear-Com was
established in 1968 and remains the market leader in providing intercoms for
entertainment, broadcast and industrial applications. The ruggedness and high
build-quality of Clear-Com products defines the industry standard. In fact, many
of our original beltpacks and main stations are still in daily use around the world.
The KB-701 speaker station is a powerful, yet user-friendly unit that can serve as
a versatile intercom station. We recommend that you read through this manual
completely to better understand the functions of the KB-701. If you encounter a
situation or have a question that this manual does not address, contact your
dealer or call Clear-Com directly at the factory. Our applications support and
service people are standing by to assist you. (Refer to Chapter 5: “Warranty” for
contact information.) Thank you for selecting Clear-Com for your
communications needs.
DESCRIPTION
The Clear-Com KB-701 speaker station is designed for use in theatres, live
performances, industrial environments, and small television facilities. It features
speech intelligibility, even at high-noise levels, and can be customized through its
programmable options.
Local or remotely controlled talking or listening is selectable and allows either
hands-on or hands-free operation. The talk button operates in momentary mode.
The integral microphone and speaker offer half-duplex communication. The
KB-701 offers both visual and audible call signaling to attract the attention of
operators.
A balanced program input allows the monitoring of external audio through the
speaker. This program input can also be used as a paging function.
The integral speaker’s volume level can be adjusted using a front-panel knob. An
internal control allows setting a minimum speaker level. An automatic speaker
switching circuit will quiet the speaker when the talk button is activated.
The KB-701 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 V-Box. The extra-thick front panel and compact surface-mount
circuitry maintains Clear-Com ruggedness. The intercom channel connects to a
plug-on-screw terminal strip. Male and female three-pin XLR connectors are
provided on the optional V-Box to offer a through connection to the intercom
channel.
Although the optional EB7-TW daughter board module allows this unit to
function on a TW line, the unit’s operation will remain single channel. Also, the
1

KB-701 SPEAKER STATION
1-2
EB7-4W four-wire daughter board module is available to allow long-distance
connections using separate pairs of wires for send audio and receive audio.
The KB-701 is compatible with all Clear-Com party-line intercoms.
OPERATION
Normal operation of the KB-701 speaker station only requires access 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 volume control to the
desired level and press the talk button when talking.
FRONT PANEL
The controls and indicators on the KB-701 front panel are shown in Figure 1-1
and are described by the following text.
Figure 1-1: Front Panel
1. Talk Button : The talk button activates the microphone feed to the intercom
channel. The button activates when pressed and deactivates when released.
The talk button lights amber when the microphone feed to the intercom
channel is on, whether activated locally by pressing the button, or activated
remotely from another station using the call signal.
The talk button lights blue to indicate that the microphone feed to the inter-
com line is off, but the station is receiving power.
2. Call Button: Pressing the call button sends a call signal on the intercom line
and causes all the call lights on other stations on the intercom channel to
light.
The call button lights red when a call signal is sent or received on the inter-
com line.
Call
Talk
Program Level
Mic
1
2
5
643
KB-701
KB-701
1-Channel
Speaker Station
Volume

KB-701 SPEAKER STATION 1-3
3. Speaker: The audio output for the KB-701 device.
4. Volume Control: Turn this control to set the speaker’s required listen level.
This control does not affect the tone alert level or the program input level.
5. Program Level Control: Adjust the program level control to set the program
audio level heard in the panel speaker.
Note: Forcing the trimpots past their stop points will damage them.
6. Integral Microphone: The microphone for the KB-701 is built into the
front panel.
INTERNAL ADJUSTMENTS AND CONNECTIONS
The controls and connectors inside the KB-701 are shown in the following figure
and described by the following text. The controls can be accessed without
completely removing the panel from its wall box or V-Box enclosure by removing
the top two screws and loosening the bottom two screws a few turns. The panel
can then be leaned out from the wall to make the controls accessible as shown in
the lower view of Figure 1-2.
Figure 1-2: Internal Controls
7. Call Alert Tone Level Control: This internal control adjusts the volume of
the call alert tone sound. This is normally adjusted when the system is set up
and shouldn’t need to be adjusted during normal operation. This feature can
be disabled by turning the control fully counterclockwise.
An audible tone alert can sound when a call signal is received on the
intercom channel. This can be useful when the operator's attention has been
drawn away from the KB-701 indicator panel. The tone alert will not sound
if a call signal is originated at the KB-701 station.
P3 Must be
installed if
no option
P1 Must be
installed if
no option
1 2
3
10
11
8
7
View from top
of KB-701
Front Panel
12
9

KB-701 SPEAKER STATION
1-4
Note: This feature is automatically turned off if the operating mode of the
KB-701 is set to any setting other than normal.
8. Minimum Volume Control: This control adjusts the minimum setting of
the intercom level control on the front panel. Setting this control can prevent
people from inadvertently turning the intercom level all the way down. This
is normally adjusted when the system is set up and shouldn’t need to be
adjusted during normal operation. This feature can be disabled by turning
the control fully counterclockwise.
9. Option Switches: Three option switches are provided. They should be
configured when the system is set up, but are not changed in normal
operation.
Note: The “on” position of each switch is toward the circuit board and the
“off” position is toward the front panel. A description of the function
of these switches follows.
•Internal Microphone Gain (S-1)— This switch determines the
microphone’s sensitivity. When the switch is in the on position, talking
should be done within 2 ft. (0.61 m) of the front panel. If it is necessary
to talk from a greater distance, the switch should be turned off. The
default position of this switch is in the on position.
•Operating Mode (S-2 and S-3)—These switches work together to
define the operating mode of the KB-701. In modes other than normal,
the call signal from other stations on the same channel activates the
KB-701. Refer to the following table:
Table 1: KB-701 Operating Mode Options
• The default position of these switches is in the off position for normal
mode, which is the only mode in which the call alert tone functions
operate. In other modes, the call alert tone is automatically disabled to
avoid interference with operation.
Note: Only normal mode may be used when the EB7-4W four-wire option
module is installed.
MODE S-2 S-3 DESCRIPTION
Normal off off
Speaker is on
Mic is activated by the talk button
Remote Page off on
Speaker turns on by remote call signal control
Mic is activated by the talk button
Remote Listen on off
Speaker is on
Mic is activated by remote call signal control or by
the talk button
Remote Listen-Page on on
Speaker turns on by remote call signal control or by
the talk button
Mic is normally on

KB-701 SPEAKER STATION 1-5
10. Intercom Line Connection: The KB-701 contains a five-terminal, plug-on
connector for intercom line connection. This connector is intended to be
unplugged from the circuit board when connecting the intercom line, and
then plugged back on when the wiring is completed. The connections for
each pin are visible on the circuit board when the connector is unplugged.
The pinout of this connector is as follows:
Pin #1 --- (NC)
Pin #2 --- (NC)
Pin #3 --- Channel A Audio
Pin #4 --- Power
Pin #5 --- Ground (Shield)
Figure 1-3: Intercom Line Cable Wiring
11. Program Input: A three-terminal, plug-on connector provides the program
input to the station. Program is fed to the speaker. This level is controlled by
the program level control. If this input is connected to the stage announce
(SA) output of a main station it can be used as a paging input. Since the level
of this input is independently adjustable from the intercom audio volume, it
can be used to override the intercom audio in all modes except remote
listen-page. The program input is also independent of the mode setting. The
pinout of the program input connector is as follows:
Pin #1 --- Ground (Shield)
Pin #2 --- + Signal
Pin #3 --- - Signal
Cable Wiring:
KB-701 Intercom
Connector
XLR
Connector
Channel
A
Pin1
Pin5
1
3
2

KB-701 SPEAKER STATION
1-6
Figure 1-4: Program Input Cable Wiring
12. Option Board Jumpers: The two jumper plugs P1 and P3 must be installed
when optional modules are not used. When the optional EB7-4W or
EB7-TW modules are used, both P1 and P3 must be removed. Save these
jumper plugs for possible future use.
Note: The KB-701 will not operate without either the jumper plugs or the
optional modules installed. The orientation of P1 in J1 and P3 in J3
does not matter.
P rogram Input
Cable Wiring:
KB-701 Program
Input Connector
XLR
Connector
Pin 1
1
3
2

KB-701 SPEAKER STATION 2-1
INSTALLATION
1. Unpack the unit and inspect it for any damage that may have occurred
during shipping.
2. Set the option switches to the default (toward the front panel) position.
3. Connect the intercom lines.
4. Install the KB-701 into the four-gang outlet box or V-Box. (For additional
information, refer to the Clear-Com System Installation Manual.)
5. Set listen levels. (Refer to “Intercom Level Control.”)
6. The speaker station should now be operating properly.
Read the rest of this manual for further information.
2

KB-701 SPEAKER STATION
2-2

KB-701 SPEAKER STATION 3-1
MAINTENANCE
This chapter provides maintenance information including a block diagram and troubleshooting tips.
Caution:These servicing instructions are for use by qualified personnel only. To reduce the risk of electrical shock, do not
perform any servicing other than that contained in the operating instructions unless you are qualified to do so.
KB-701 BLOCK DIAGRAM
The following is a block diagram of the KB-701 speaker station:
Figure 3-5: Block diagram of the KB-701
EQ/
LIM
Talk
Min
Vol
Call
Light
Call
Intercom
Volume
TW Option
Intercom
Speaker
Power
(NC)
Call Send &
Receive
Microprocessor
Talk
Balanced
Program
Input
Speaker
Mute
Program
Mute
Mic Mute
Common
+30 VDC
Ground
Operating
Mode
Options
Mic Gain
Program
Level
Call Alert
Tone Level
4-Wire
Input
4-Wire
Output
2-Wire / 4-Wire
Select
Rectifier 16 VAC Power
4-Wire
Option
Panel Mic
3

KB-701 SPEAKER STATION
3-2
TROUBLESHOOTING TIPS
SYMPTOM CAUSE SOLUTION
System does not operate. The
talk button does not light.
(1) No intercom connection to the
KB-701. If the EB7-4W four-wire
option module is connected, no AC
power is reaching the KB-701.
(1) Check connections and cable.
(2) The KB-701 has an internal
failure.
(2) Unit requires servicing.
System operates incorrectly. The
talk button does not turn amber
when the talk button is pressed,
or stays amber until talk button
is pressed and the speaker is off
when it should be on.
(1) Operating mode switches are set
incorrectly.
(1) Refer to the option switch setting
section of this manual.
Speaker does not operate. The
talk light turns amber when talk
button is pressed.
(2) Intercom level knob turned all the
way down.
(2) Adjust control appropriately.
(3) Speaker plug or wiring has come
loose.
(3) Make sure speaker is connected
internally.
(4) Plug P3 missing on circuit board. (4) Plug P3 must be installed in jack
J3 if the EB7-4W or EB7-TW option
is not used.
Hum or buzz in system. (1) Inductive pickup caused by close
proximity of this speaker station or
connected stations to power lines or
transformers.
(1) Relocate the offending unit or
wiring. If the cable run is
exceptionally long, consider adding
and using the EB7-4W four-wire
option module. (Requires an
additional four-wire interface at the
opposite end of a “long run.”)
System feedback (Acoustical). (1) Intercom level control at this
station or another station is set too
high.
(2) Adjust.
(2) Channel unterminated. (2) Set the main station or power supply
termination switch for the appropriate
channel to the on position.
(3) The KB-701’s microphone is too
close to an open speaker on the same
channel.
(3) Change the unit’s location.

KB-701 SPEAKER STATION 3-3
Table 2: Troubleshooting Tips
Excessive crosstalk. (1) High DC resistance in ground
return.
(1) Use heavier cable; add additional
conductor(s) to ground return. If the
cable run is exceptionally long,
consider adding and using the
EB7-4W four-wire option module.
(2) Multi-channel cable pairs are not
individually shielded.
(2) Replace cable with individually
shielded pairs.
Program signal sounds distorted. (1) Program level control set too high. (1) Turn the program level control
counter-clockwise.
(2) Overload of program input circuit. (2) Reduce the gain of the program
signal at the source, such as an audio
mixer.
The call signal does not
function.
(1) Excessive DC loading of intercom
line.
(1) Remove any audio transformers or
other equipment that may be
connected across the intercom line. If
equipment other than Clear-Com
intercom equipment must be
connected to the intercom line, please
contact Clear-Com application or
service personnel for information or
recommendations.
(2) Far too many terminations on the
intercom line.
(2) Check all main stations and power
supplies to make sure each intercom
channel is terminated at only one
point.
(3) Plug P1 missing on circuit board. (3) Plug P1 must be installed in the J1
jack if the EB7-4W or EB7-TW
options are not used.
SYMPTOM CAUSE SOLUTION

KB-701 SPEAKER STATION
3-4

KB-701 SPEAKER STATION 4-1
TECHNICAL SPECIFICATIONS
KB-701 SPEAKER STATION
dBu is an absolute measurement. 0 dBu is referenced to 0.775 volts RMS
Program Line Input
Maximum Level before Clipping >= 20dBu
Input Impedance >= 5K
Ω
Speaker Output
Load Impedance >= 4 Ω
Max Output Level before 1% Distortion 20dBu ± 2dBu
Party Line Output
Off Noise < -74dBu
Output Impedance >10K
Ω
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
4

KB-701 SPEAKER STATION
4-2
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 - 122
o
F (0 - 50
o
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.