Tech Works IC-52B Operation And Installation Manual

IC-52B

DUAL CHANNEL

AUDIO INTERCOM AMPLIFIER

OPERATION AND INSTALLATION

MANUAL

Tech Works

“Making Specialized Communication Easy”

A Division of: United Communication Technology, Inc.

22347 La Palma Ave., Suite #107, Yorba Linda, CA 92887

Direct Line: 714-694-1040 Fax: [phone] Toll Free: 1-800-813-1080

TM

Web site www.tech4people.com 2/15

How to use this Manual

Those wishing to use one of the standard Configuration Templates, should first read the

Overview, and then proceed to the appropriate Configuration Template for your application.
The Setup, Adjustments section should also be read before installation.

For those users who wish to do their own engineering then all sections may be useful. You may
also wish to contact a Tech Works application engineer for assistance.

Table of Contents

Table of Contents…………………………………….

List of Illustrations……………………………….……

Overview…………………………………………….….

Specifications…………………………………………..

Functional Diagram and Explanation………………..

Mechanical Details….…………………………………

Front Panel controls and Indicators…….…………..

Rear Panel Connections.……………………………..

Main Board Jumper Options……...…………………..

Setup, Adjustments…………………………………….

Application Templates…………………………………..

Mounting Options……………………………………..…

Accessories………………………………………………

Page 2

Page 3

Page 4

Page 6

Page 5

Page 8

Page 9

Page 10

Page 13

Page 17

Page 21

Page 25

Page 26

2/15 Page 2 of 26

List of Illustrations:

Functional Diagram……………………………………....

Mechanical Drawings…………………………………....

Front View……..……………………………….………….

Rear View……………………………….…….…………...

Simplified Block Diagram…………………….…………..

PCB Jumper Location.……………………………….…..

General Configuration Template………………………...

Ticket/Drive-Through Window VOX application……….

Cath-Lab Application with Doctor Music………………..

Interview Application with Conversation Logging………

IC-52B-DM Desk Mount…………………….……………..

IC-52B-WM Single Wall Mount…………………………..

IC-52B-WM2 Dual Wall Mount……………..…………….

IC-52B-RM Rack Mount……………………..……………

IC-52B-RM2 Rack Mount…………………………………

Accessories………………………………………………..

Page 5

Page 8

Page 9

Page 10

Page 12

Page 13

Page 21

Page 22

Page 23

Page 24

Page 25

Page 25

Page 25

Page 25

Page 25

Page 26

2/15 Page 3 of 26

Overview

The IC-52B is the most versatile Audio Intercom ever built. Yet it is also the easiest to integrate
into your design. Configuration Templates support every common application. Follow the
Setup and you’re done. If there is not a template for your application, give us a call; we will be
pleased to assist you to configure the IC-52B into your design.

The audio quality of the IC-52B is superb. Noise and distortion are very low. Selectable
equalization optimizes voice communications. The Automatic Level Control assures optimum
performance. There are separate controls for Audio Level, and Reach. Once set, the Audio
Level remains constant over wide dynamic input range. The independent Reach Control allows
for optimized accommodation of the input signal level. The user may wander throughout the
room, and still be heard at a nearly constant level without any operator adjustments!

Hands-Free operation is easily achieved with the IC-52B. The selectable Voice Operation
(VOX) operates flawlessly. Electronic switching takes less than 3mS. Setup indicators make
adjustments easy

The IC-52B incorporates two selectable Notch-Filters to reduce acoustic feedback. One filter
has an optimized frequency range to compensate for poor room acoustics. The other has a
higher frequency range to reduce microphone to wall/glass resonance.

In every way the IC-52B is the Universal Audio Intercom Amplifier Solution. The logic interface
has a plethora of Inputs and Outputs. However standard functions require few wires. The
Indicators are comprehensive, yet a simple. The interface is fully configurable, with jumpers,
however common functions are preset. Audio controls are on the IC-52B front panel.

Line Level, 0dBm Outputs may be configured for Paging, Monitoring or Logging
Jumpers allow for Audio Signal Selection, and Keying

The Tech Works PA-BUSS Line Level Output is fully configurable.
Pre-emptive Music is accommodated using the Tech Works PA-402 Power Amplifier

Modular Construction makes the IC-52B ideal for integrated designs. The unit is small; mounting
is flexible, and easy. Power is from a Universal Plug-in D.C power adapter. All I/O is through
Euro-Style connectorized barrier strips.

The IC-52B has major improvements, over its predecessor:

Universal Microphone/Line Inputs
Phantom Power now 22 Volts Current Limited (used to be 10 Volts)
Gain Structure change; Rotary Microphone Gain Control, Trim-Pot Speaker Level
25 Volt, 10 Watt Speaker Outputs
Line Outputs, inbuilt, no Option PCB required
PA-BUSS Output Connector, Easy Connectivity to other Tech Works Products
Privacy Tone removed

2/15 Page 4 of 26

IC-52B Functional Diagram

Each audio path or channel has its own audio control section, which provides Automatic Level
Control, Amplifier Muting and other functions. These can be operationally assigned for specific
applications based on placement of removable jumpers inside the unit.

A two band notch filter is included to reduce feedback. These filters are shipped from the factory
disabled; they can be enabled by moving jumpers to the Remote or Operator Channel. Notch
filters must be set up in the field.

The Logic Control section provides the interface of the control contact inputs as well as the
audio control for muting audio signals depending on how the unit is configured. If it is configured
for full duplex then only muting is enabled. If the Call In feature is active, the logic controls the
tone interfaces to the Operator Speaker amplifier.

Configurable Line Level Outputs are provided for Paging, Monitoring or Logging

A PA-BUSS output may be used with a PA-402 Power Amplifier for Pre-emptive Music

2/15 Page 5 of 26

Specifications

General:

Dual Channel Universal Audio Intercom Amplifier
Inputs: R.F. and static electricity protected
Outputs: short circuit protected
Frequency Response: 250 Hz to 10 KHz
10-Watts RMS Sine Wave output, 25 Volts (Balanced)
Distortion at full voltage output < 1% T.H.D.
Power Supply Required: 24 Volts DC @ 2.2 Amps for full rated output
Unit is intended to use with class 2 power source (Sold Separately)
24 Volts D.C. 48-Watts Maximum

Microphone/Line Inputs:

Both Operator and Remote

Configured for a Microphone Level Input:
2000 Ohms Balanced

-76dBm or -60dBm (Selectable) minimum input (Balanced) for full rated output
Selectable Equalization - 3 settings optimized for voice communication
Selectable Phantom Power (22 Volts, Short Circuit Protected)

Configured for a Line Level Input:
2000 Ohms Balanced, 1000 Ohms Unbalanced
Balanced input -35dBm to +5dB or -20dBm to +20dB Accommodation range Un­Balanced Input -30dBm to +10dB or -10dBm to +20dB Accommodation range

Speaker Outputs:

Both Operator and Remote

Balanced
25-Volts, 10-Watts (Maximum)

Line Level Outputs:

Transformer Isolated ~0dBM

Remote Microphone, after signal processing

May be keyed by control inputs

Mixed Output

Selectable summing of any of:
Remote Microphone, after signal processing
Operator Microphone, after signal processing
Call Tone

All signals may be keyed by control inputs

2/15 Page 6 of 26

PA-BUSS Output, signal pairs:

Configurable with internal jumper options

Power, 23 Volts, 350 Milli-Amps fold back current limited, short circuit current ~ 40MA
Line Level Output, Transformer Isolated ~0dBM
ALERT, indicates attention is requested

Automatic Level Control:

Operator and Remote

Greater then 40dB Automatic Level accommodation

Fast Attack, <10mS

Feed Forward Control, no ‘Pumping’

Independently adjustable Microphone Gain

Notch Filters
Selectable Channel: Operator; Remote; Not used

Notch Depth > 10dB
Two tandem frequency ranges: 250-1000Hz; 750-3000Hz

Voice Activation (VOX)

VOX setup indicator

Electronic Switching <3mS

Silent Switching, no Pops

Adjustable Recovery Delay

Call Tone

Uses Operator Speaker

Selectable

Continuous, or One Shot

Adjustable Level

2/15 Page 7 of 26

Mechanical and Electrical:

1U, Half Rack, 8½” X 1¾” X 6”

Mounting Options: Table-Top; Under Counter; Rack

Approximately 3 lbs

Modular aluminum enclosure

Euro-Style connectorized barrier strips

SIDE VIEW FRONT VIEW

DESK MOUNT TOP

DUAL WALL MOUNT TOP

RACK MOUNT TOP

WALL MOUNT TOP

2/15 Page 8 of 26

FRONT PANEL CONTROLS AND INDICATORS

IC-52B Front View

Power Indicator

Green when operating normally

Call Tone Level

Control trimpot, sets the level of the tone from the Operator speaker associated with a

‘Call’ button closure.

“OPERATOR” (Remote Microphone to Operator Speaker)

Active Indicator

Green: Remote Microphone is keyed, Operator Speaker Amplifier is ON

‘Reach’, Remote Microphone Gain

16 Position Switch, 3dB/step

Sets preamplifier sensitivity for Normal Microphone input level

‘Reach’ Level Indicator, Remote Microphone Level

Off, Microphone Off

Green, low input level

Green, flashing to Red, Normal Operation

Speaker Level

Control trimpot, sets the listening level from the Operator Speaker

Voice Activation

VOX Sensitivity trimpot, when fully CCW, VOX is disabled

VOX Setup Indicator, Green when Operator is listening, or muted,

Red when Operator is talking (See setup instructions)

Anti-VOX Trimpot (Negates inside Speaker Microphone acoustic coupling)

Notch Filters:

‘LO’ Band Notch Filter trimpot, 250 to 1000Hz
‘HI’ Band Notch Filter trimpot, 750Hz to 3000Hz

“REMOTE” (Operator Microphone to Remote Speaker)

Active Indicator

Green: Operator Microphone is keyed, Remote Speaker Amplifier is ON

2/15 Page 9 of 26

‘Reach’, Operator Microphone Gain

16 Position Switch, 3dB/step

Sets preamplifier sensitivity for Normal Microphone input level

‘Reach’ Level Indicator, Operator Microphone Level

Off, Microphone Off

Green, low input level

Green, flashing to Red, Normal Operation

Speaker Level

Control trimpot, sets the listening level from the Remote Speaker

REAR PANEL CONNECTIONS

ACTIVATE SW

OP MIC (-)

OP MIC (+)

COMMON

COMMON

OP SPKR (-)

OP SPKR (+)

SUTOFF SW

VOX INHIBIT

CALL SW

PTT SW

COMMON

REM MIC (-)

REM MIC (+)

REM SPKR (-)

REM SPKR (+)

COMMON

OP ACTIVE

CALL

PA (-)

PA (+)

REM (+)

REM ACTIVE

REM (-)

CHASSIS

COMMON

+24VDC

IC-52B Rear View

Audio I/O, Euro Style Barrier Strip

Operator Microphone/Line Input, Configurable, see Specifications, and Jumper Options

Operator Speaker Output

Remote Microphone/Line Input, Configurable, see Specifications, and Jumper Options

Remote Speaker Output

Page Output Line Level Output, after signal processing, ~0dBm

Remote Microphone Line Level Output, after signal processing, ~0dBm

PA-BUSS Output, RJ-45 Connector, signal pairs:

Power, 23 Volts, current limited, shared with IND PWR
Line Level Output, after signal processing, ~0dBm

ALERT, indicates attention is requested

2/15 Page 10 of 26

Control Inputs, Euro Style Barrier Strip, common sensing for Switches, or PLC

Switch Common

Shutoff (Lowest Priority) - Active low, momentary, or sustained, see below

Disables both Operator and Remote Speakers

(Overridden by “Activate”, “Push to Talk”)

Power on, quiescent state, Operator Shutoff

Activate - Active Low, momentary, or sustained

Overrides “Shut Off”,

Cancels Call Tone (Jumper Option)

Cause Privacy Tone to be sent (Jumper Option)

Push to Talk (PTT) - Active Low, momentary or sustained

Forces the Remote speaker on while depressed (Sustained)

Cancels “Call Tone” (Jumper Option)

Activates the Intercom if Inactive

VOX Inhibit - Active low, sustained

Defeats VOX while depressed,

Provides privacy to the Operator microphone, when using VOX

Call - Active low, momentary

Causes ‘Call Tone’ to be sent to the Inside speaker

Causes Call Light to flash

Indicator Outputs, Euro Style Barrier Strip

Open Collector Transistors, Common sensing for Indicators, or PLC V<30Volts, I<200MA

Common

Remote Active, Remote Microphone Keyed, low when Keyed

Operator Active, Operator Microphone is Keyed, low when Keyed

Call Indicator, flashes Low when Call Tone is present

Power, Euro Style Barrier Strip, connected in parallel with Barrel Connector

+24 Volts, DC
Power Supply Return
Chassis

Barrel Connector, two in Parallel
PJ-102A, center connector positive

2/15 Page 11 of 26

Simplified Block Diagram

2/15 Page 12 of 26

Jumper Options (Refer to the Block Diagram for Jumper Function)

Tech Works

IC-52

REV- B-1

REM MIC ON

CALL TONE RUNNING

REMOTE MIC

OPERATOR MIC

OP MIC ON

CALL TONE

CALL TONE

PA OUTPUT

ALERT

P16P17P18P19P20P21P12

AUDIO

SOURCES

ON OFF

CONTINUOUS

REM PHANTOM

P7

OFF ON

OP SPKR ON

REM SPKR ON

P15 P14

ALWAYS

SWITCHED

CHANGEOVER

DELAY

P13

10 mS

200 mS

ONE CYCLE

REM MIC ON

P11

ALWAYS

SWITCHED

UNUSED

MIC MIC

OPREM

REM GAIN OP GAIN

P10

LO HI OFF ON LO HI

P9 P8

HI CUT

REM EQ

MED CUT

NOTCH
FILTER

P6

OP PHANTOM

P1

P3 P2

HI CUT

P4

OP EQ

MED CUT

OP MIC ON

P5

ALWAYS

SWITCHED

IC-52B Main Board Jumper Locations

Control Functions Jumpers:
Change Tone Shutoff

The Call Tone is edge triggered by a Switch Closure

The Call Tone is Cancelled by the a PTT Switch Closure

The Call Tone may run a single cycle and Stop ONE CYCLE

Or Run continuously until the PTT switch is pressed CONTINUOUS

Change Over Delay

These Jumpers control the switching time from the Remote Speaker being active, to the
Remote Microphone turning on. When the Remote Speaker is also being used as the
Remote Microphone it is necessary to have a small delay or an acoustic pop will be heard at
the Operator position. The amount of delay is determined by experiment.

Delay:

~10mS, Normal for separate Microphone and Speaker 10mS

in a non-reverberant environment

Severe Reverberant Environment 200mS

Or Remote Speaker also being used as a Microphone

2/15 Page 13 of 26

Audio Input Jumpers:

Universal Microphone/Line Input both channels:

This input can accommodate a wide range Microphone or Line inputs
The Microphone Sensitivity is adjustable with the 16 Position Rotary Switch
With ~3db/Step for a 45 dB range
By using the Gain Switch, and Jumper options the total Range is -75dB to +20dB

The Signal is processed with an ALC, to assure the Output never exceeds 0dBm
Indicators allow the Microphone Gain to be adjusted to the optimal level

Phantom Power:
Terminating Resistors referenced to +22Volts, Current limited @ 7MA , ON
Terminating Resistors referenced to Common, OFF

Gain Range:
Input Gain reduced 15db, LO
Full Gain, HI

EQ Jumpers (Two):
Both Jumpers, upper position, lowest frequency Roll-off
(Used with most gooseneck and Hanging microphones)

Only MED CUT Jumper Upper Position, Medium frequency Roll-off
(Used with most flush mounted microphones)

Only HI CUT Jumper Upper Position, Highest frequency Roll-off
(Used with most Speakers used as a microphone)

Both Jumpers Lower Position, (Line Input)
~170Hz Roll-off, Sensitivity reduced to –35Bm for full Output

Note:
For a Balanced Line Level Input the LO Gain Position is also used

The Accommodation Range for full output is ~ -10dBm to +20dBm (With 10dB of Headroom)

Notch Filters

A Notch Filters are useful in Environment with one or two strong Resonant Modes
Examples are floor to ceiling modes, or small Room wall-to-wall modes
‘Notching out’ these resonances increases intelligibility, and reduces feedback
The Notch Filters may be used in either Channel, or not at all

Notch filters are shipped (default) in the Remote to Operator channel.
The factory settings are: LO, fully CCW, HI, Fully CW; the Notch Filters are essentially disabled

2/15 Page 14 of 26

Audio Switching Configuration Jumpers

The IC-52B has two Audio Channels, designated as
Remote Microphone to Operator Speaker and Operator Microphone to Remote Speaker
With all Signal Flow Jumpers in place, Half Duplex Operation is supported

Half Duplex Operation, the Microphone Inputs and Speaker Outputs are sequenced:

When the Operator is “Listening”:
The Remote Microphone is ON
The Operator Microphone is OFF
The Operator Speaker is ON
The Remote Speaker is OFF

When the Operator is “Talking”:
The Remote Microphone is OFF
The Operator Microphone is ON
The Operator Speaker is OFF
The Remote Speaker is ON

However, the control of the Microphones and Speakers are controlled by Jumpers

Any of these sections may always be ON

These ‘always’ selections are useful in implementing in implementing:

Always Listening, Push to Talk
Full Duplex Operation

Always Monitoring to the PA-BUSS Output
Etc.

Operator Microphone ON:
Always On ALWAYS
Sequenced SWITCHED

Remote Microphone ON:
Always On ALWAYS
Sequenced SWITCHED

Operator Speaker ON
(Also Keys Remote Microphone):

Always On ALWAYS
Sequenced SWITCHED

Remote Speaker ON
(Also Keys Operator Microphone):

On when the Intercom is Active ALWAYS
Sequenced SWITCHED

2/15 Page 15 of 26

PA-BUSS Output Jumpers

The PA Buss is provided for easy interface to other Tech Works PA-Buss products such as the
PA-402 Music and Paging Amplifier.
There are several Audio Selection Choices, which are summed. These selections determine
what signals are sent to the PA-402 and when they are sent.

What to send:
There are several Audio Selection Choices, which are summed
Remote Microphone: ON OFF
Operator Microphone: ON OFF
Call Tone: ON OFF

When to send
The PA-BUSS Output, ALERT Signal (Keying Signal) is selectable, logical OR’ed
Remote Microphone: ON OFF
Operator Microphone: ON OFF
Call Tone Running: ON OFF

The PA-BUSS (Audio Distribution Buss) has four signal pairs:
“Buss Power” (Option) Current Limited, 23-Volts
“Program” (Audio Option) Background Audio or Music
“Page/Communications” (Audio) Page/Monitor/Communications Audio
“Alert” (Control) Indicates Action is Requested

The IC-52B, PA-BUSS OUTPUT is always powered, 23 Volts, at a Maximum of 350
Milliamps

2/15 Page 16 of 26

Initial Adjustments, each channel:

There are both Input and Output Controls with associated Indicators
When the Indicators are green the associated control is enabled

Only attempt adjustments if the associated indicator is lighted green!

Do each channel separately, Remote to Operator, then, Operator to Remote

Digital Rotary Switches (3dB/Step) are used to set Reach, Microphone Gain
The nominal Reach, Microphone Gain is ~6dB, or less, into limiting

Reach, Microphone Gain is always setup first
Initially, the Output level controls should be set to minimum (No Output)

Limiter Setup with a Microphone:
Always do first

Provide a normal input to the Microphone, or Line input

Insure the Microphone is Keyed, the indicator is Green

Advance the “Reach, Microphone Gain”, from “0” until the Talk Level indicator

just flashes red

If this setting is below "2" move the Gain Range Jumper to the "LOW" Position

Advance the “Reach, Microphone Gain” no more than two clicks (6dB into limiting)

If the Notch Filters are going to be used, move the Jumpers to the appropriate channel and do
those adjustments next. Then you will need to redo the adjustment above of the effected
channel again before proceeding

Speaker Level setup:
Assure there is an audio input
With normal audio input levels, with Inputs and outputs keyed (Both Indicators Green)

Set the Speaker Listening Level

Call Tone Level:

The Call Tone alert signal comes through the Operator’s speaker. The call level is independent
of the voice communications level, and may be set to any appropriate level, from fully off,
to very loud.

Setup is accomplished by activating the ‘call signal’ by pushing the ‘Call Switch’. Adjust the Call
Tone alert to a suitable level.

2/15 Page 17 of 26

VOX and Anti-VOX:

When VOX is not used, the VOX Threshold must be set Fully CCW

This disables VOX, and sets the timing for Push-to-Talk Operation

Proper Speaker Microphone placement is necessary for VOX operation. The sound level from
the operator speaking into the microphone should be greater than sound level at the
microphone from the operator’s speaker.

Do the Level and Reach adjustments first.
Note the setting of the Operator Speaker Level Control

Setup is accomplished with the use of an Assistant (best) or a Radio, or other sound source.
The sound source should be set for the normal expected input level at the Remote microphone.

Turn both the VOX and Anti VOX pots fully counterclockwise.

Turn the ‘Operator Speaker Level’ control fully Counter Counterclockwise, so that there is no
sound coming from the Operator’s speaker. Speak at a normal level and distance into the
Operator microphone while advancing the VOX trimpot clockwise until the VOX indicator flashes
red and the direction indicators reverse.

Reset the Operator Speaker Level control to its normal setting. The Intercom may intermittently
switch directions; this is normal. Advance the Anti-VOX clockwise until the VOX indicator is
green with brief flashes of red. The intercom should no longer be intermittently switching
directions.

When you speak into the Operator Microphone at a normal level the direction should easily
change.

2/15 Page 18 of 26

Notch Filter Setup: Do after initial adjustments

Notch Filters can greatly reduce feedback; however they cannot make up for
poor acoustic isolation

When shipped from the factory the Notch Filters not used.
The Notch Filter Configuration Jumpers must be moved to the appropriate channel first

The factory settings are: LO, fully CCW, HI, Fully CW; the Notch Filters are essentially disabled

There are two methods to adjust the Notch Filters; both entail forcing a feedback condition
The one below is required if access to the jumpers is unavailable

If the covers are off the IC-52B, the second method may be easier; see next page

Method 1:
Move Speaker wires

The Notch Filters are adjusted by moving the Speaker wires so the channel with the
Notch Filters is temporarily connected to the Room Speaker with the microphone
To induce feedback

There are two distinct primary resonance modes in most installations. One is room resonance;
usually one mode is most prevalent, such as floor to ceiling resonance. This frequency is
usually on the order of a few hundred cycles. The second mode is the distance of the
microphone from a near object. This frequency is much higher near 1000Hz. The IC-52B
incorporates two filters in tandem, one a low Band Filter 250Hz to 1000Hz, and the other a High
band Filter 750Hz to 3000Hz.Adjust the Notch Filters one at a time. Increase the Speaker Level
Control until feedback occurs.

Make a rough determination of the frequency (or measure the frequency with a counter).
If the feedback is below ~800Hz, adjust the ‘Lo Notch’ until feedback ceases. If the feedback is
above ~800Hz, adjust the ‘Hi Notch’ until feedback ceases. (This is a 20-turn pot so it is best to
start from one extreme, and slowly turn the pot in the other direction

Increase the Speaker Level Control until feedback occurs again, if it is at the same frequency;
try finely adjusting the same filter to see if the feedback can be eliminated. If the frequency is
different, and in the other range not already tuned, repeat the steps above

If only one Notch Filter is required, the other filter should be set at the extreme of its range.
Fully CCW (lowest frequency) for the LO filter, and fully CW (highest frequency) for the HI filter.

After the Notch Filters are adjusted, move the speaker wires and redo the initial adjustments.

Note:
Before making any adjustments assure there are audio Inputs and Outputs

All the associated indicators must be lighted green

2/15 Page 19 of 26

Method 2:
Jumper Settings

The Notch Filters are adjusted by moving the Configuration Jumpers so the Audio from
the microphone temporarily appears at the Speaker in the same room, to induce
feedback.

REMOTE

TO

OPERATOR

Also Jumper
Remote Speaker
Always On

OPERATOR

TO

REMOTE

Also Jumper
Operator Speaker
Always On

Temporary Jumper Setting for Notch Filter Setup

There are two distinct primary resonance modes in most installations. One is room resonance;
usually one mode is most prevalent, such as floor to ceiling resonance. This frequency is
usually on the order of a few hundred cycles. The second mode is the distance of the
microphone from a near object. This frequency is much higher near 1000Hz. The IC-52B
incorporates two filters in tandem, one a low Band Filter 250Hz to 1000Hz, and the other a High
band Filter 750Hz to 3000Hz.Adjust the Notch Filters one at a time. Increase the Speaker Level
Control until feedback occurs.

Make a rough determination of the frequency (or measure the frequency with a counter).
If the feedback is below ~800Hz, adjust the ‘Lo Notch’ until feedback ceases. If the feedback is
above ~800Hz, adjust the ‘Hi Notch’ until feedback ceases. This is a 20-turn pot so it is best to
start from one extreme, and slowly turn the pot in the other direction

Increase the Speaker Level Control until feedback occurs again, if it is at the same frequency;
try finely adjusting the same filter to see if the feedback can be eliminated. If the frequency is
different, and in the other range not already tuned, repeat the steps above

If only one Notch Filter is required, the other filter should be set at the extreme of its range.
Fully CCW (lowest frequency) for the LO filter, and fully CW (highest frequency) for the HI filter.

After the Notch Filters are adjusted, move the Jumpers to their correct position and redo the
initial adjustments.

Note:
Before making any adjustments assure there are audio Inputs and Outputs

All the associated indicators must be lighted green

2/15 Page 20 of 26

Application Templates

The Application Templates in this section cover some of the most common applications of the
IC-52. They are meant to allow the user to easily configure a standard system. They are also
useful as a guide for those configurations that are almost standard. The IC-52 is extremely
versatile; almost any design can be accommodated. If you need additional help please contact
a Tech Works applications engineer.

"CALL"

“OP MIC ON”

“REMOTE MIC ON”

"SHUT OFF"

"TALK" (OPERATOR MIC ACTIVE)

"ACTIVATE" (REMOTE MIC ACTIVE)

VOICE

25 VOLT

MICROPHONE

SPEAKER

Default Jumper Settings

2K

2K

"VOX INHIBIT"

"CALL"

VOICE

25 VOLT

MICROPHONE

SPEAKER

P16P17P18P1 9P20P21P12

ONE CYCLE

CONTINUOUS

2K

P7

P15 P14

ALWAYS

SWITCHED

P13

10 mS

200 mS

P11

ALWAYS

SWITCHED

HI CUT

P6

P1

P10

REM EQ

MED CUT

P4

HI CUT

OP EQ

MED CUT

P5

ALWAYS

SWITCHED

Setup:

The normal setup procedures for the intercom should be done first. The chart below shows the
setup for several typical applications. Place the jumpers as shown above for the functions
shown above. Then follow the setup procedures detailed previously.

2/15 Page 21 of 26

Ticket / Drive-Through Window, VOX application:

Ticket and Drive Through Windows include those applications such as the Movie
Theaters, Bank Drive Through Tellers, Prison Inmate Personal Items Return, and even
the local Landfill or Weigh Station. The IC-52 provides a flexible, quality communication
between the customer and the service attendant.

"CALL"

“OP MIC ON”

“REMOTE MIC ON”

2K

2K

"SHUT OFF"

"TALK" (OPERATOR MIC ACTIVE)

"CALL"

2K

VOICE

25 VOLT

MICROPHONE

SPEAKER

VOICE

25 VOLT

SPEAKER

The typical Drive Through or Ticket Window Intercom configuration does not use a separate
outside or Remote microphone. Simply jumper the REM MIC (+) to the REM SPKR (+) and the
REM MIC (-) to the REM SPKR (-) and the standard 25 volt speaker becomes a weather and
vandal resistant microphone.

P7

P15 P14

ALWAYS

SWITCHED

P16P17P18P1 9P20P21P12

ONE CYCLE

CONTINUOUS

P13

10 mS

200 mS

P11

ALWAYS

SWITCHED

HI CUT

P6

P1

P10

REM EQ

MED CUT

P4

HI CUT

OP EQ

MED CUT

P5

ALWAYS

SWITCHED

Jumper Settings must be changed from the default. Remove the top and move the “OP SPKR
ON” jumper P14 to the “SWITCHED” or left position.

2/15 Page 22 of 26

Procedure Room / Cath-Lab Application with Music Control Interface:

Today medical professionals expect high quality audio communications in a variety of facilities
commonly called Cath Labs. This may include a variety of Operating suites and other
applications such as infant monitoring that have nothing to do with Cardio Cath Labs.

"SHUT OFF"

“LISTEN" (REMOTE MIC ACTIVE)

"TALK" (OPERATOR MIC ACTIVE)

"CALL"

VOICE

25 VOLT

MICROPHONE

SPEAKER

VOICE

25 VOLT

MICROPHONE

SPEAKER

The typical medical Procedure Room Intercom configuration uses the special features
specifically designed into the IC-52B such as Operator Listen Always On and Procedure Room
Music Mute. Tech Works microphones include indicator lamps to tell the Operator when the
intercom is in the Listen mode or when the Microphone is active for both Talk and Listen

P7

P15 P14

ALWAYS

SWITCHED

P16P17P18P1 9P20P21P12

ONE CYCLE

CONTINUOUS

P13

10 mS

200 mS

HI CUT

P6

P1

P10

REM EQ

MED CUT

P4

HI CUT

OP EQ

MED CUT

The IC-52B comes with the default jumper settings set for Procedure Room operation.
You should not need to move any internal jumpers for proper operation.

2/15 Page 23 of 26

P11

ALWAYS

SWITCHED

P5

ALWAYS

SWITCHED

Interview Application with Conversation Logging:

In security and detention there are often needs to interview a detainee and observe the
conversation from an isolated room or even miles away over video link. Clear audio is
critical to observing the interview and recording the conversation.

The IC-52B includes balanced, transformer isolated, recording outputs with automatic level
control for line level audio to any professional recording equipment. The typical Interview Room
configuration uses the features such as Selective Recording of what was said or what was
heard depending on Jumper settings.

P7

P15 P14

ALWAYS

SWITCHED

P16P17P18P1 9P20P21P12

ONE CYCLE

CONTINUOUS

P13

10 mS

200 mS

P11

ALWAYS

SWITCHED

HI CUT

P6

P1

P10

REM EQ

MED CUT

P4

HI CUT

OP EQ

MED CUT

P5

ALWAYS

SWITCHED

Shown with ‘what was heard’ configuration. This is the default jumper configuration.

2/15 Page 24 of 26

Mounting Options

Desk Mount

IC-52B-DM

Wall or Under Counter Mount

IC-52B-WM

PA-402

PROGRAM AND

PAGING AMPLIFIER

POWER

PROGRAM

LEVEL

ACTIVE

PAGE

ACTIVELEVEL

IC-52-WM2 Shown with an IC-52B and a companion PA-402

IC-52-RM Rack Mount Option

IC-52-RM

PA-402

PROGRAM AND

PAGING AMPLIFIER

POWER

PROGRAM

LEVEL

ACTIVE

PAGE

ACTIVELEVEL

IC-52-RM2 Shown with an IC-52B and a companion PA-402

mounted in a single rack space

2/15 Page 25 of 26

PA-402

PROGRAM AND
PAGING AMPLIFIER

POWER

PROGRAM

ACTIVE

LEVEL ACTIVELEVEL

PROGRAM

PA-402

PROGRAM AND
PAGING AMPLIFIER

LEVEL

POWER

Accessories

CS540 WIRELESS HEADSET - When the user requires mobility, privacy,

and quality the CS540 does it all in a light weight rechargeable package with
an integral over the ear mounting band. The CS540 requires the HS-1
adaptor sold seperately.

PRO 45 HANGING MICROPHONE - In the procedure room area such as an
operating table the PRO 45 is a high quality condenser microphone with
cardioid pattern for excellent signal to noise and 25’ cable included for easy
connection.

PRO 47T -PLUS - MICROPHONE with a DESK STAND BASE and Two
Switches. This is the perfect solution for the Cath Lab operator location. It is

an attractive professional assembly complete with a Blue “Talk” and an
Amber “Listen” switch to allow complete control of communication flow.

PRO42 - is a wide-range miniature condenser microphone with a hemi-

cardioid polar pattern. It was designed for surface-mounted
applications in high-quality sound reinforcement and other demanding
sound pickup situations like procedure room boom arms.

HM-1 - Hidden Microphone - The HM-1 is an Omni-Directional Condenser
Microphone with an electronically balanced preamp designed for interview
pick up. This is a complete assembly including a 1-gang face plate and
mounting hardware.

FS-1-PLUS - CALL / CONTROL SWITCHES - The FS-1-PLUS which
includes a 15 foot cable with connectors and wall plate. Both offer a variety of
hands free call in and control options.

System 21 -

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hhiigghh--qquuaalliittyy 88"" lloouuddssppeeaakkeerr,, 2255VV ttrraannssffoorrmmeerr aanndd ppeerrffoorraatteedd sstteeeell ggrriillll..
TThhiiss uunniitt iiss mmaaddee ttoo ““BBlliinndd MMoouunntt”” iinn ttoo hhaarrdd cceeiilliinnggss.

System 5 CEILING MOUNT SPEAKER System- This is a complete
assembly including a back box and mounting hardware. The System 5 comes
complete with a 25 volt transformer or is available as the System 5-8 in 8
Ohm for Music playback.

IC52-WM WALL OR UNDER COUNTER MOUNT - The IC-52 is available
with a top that provides 1” metal tabs on each side of the unit for easy

PAGE

PAGE

ACTIVE

ACTIVELEVEL

attachment to either a wall or the underside of a counter. Also available in a
side by side IC52-WM2 .

IC52-RM RACK MOUNT - IC-52 units can be rack mounted as either a single
unit, dual units (side by side), or as companions with accessories like the SA­202 Stereo Amplifier. The rack mount is 1 rack unit (1-7/8”) High by EIA 19”
Wide.

.

2/15 Page 26 of 26