TB-6R - Intercom Sonifex - Free user manual and instructions

Product Type	6-Way Talkback Intercom, 19-inch Rack Mounted
Model	TB-6R
Brand	Sonifex
Dimensions (H x W x D)	8.9 cm (2U) x 48.3 cm (19") x 18.5 cm
Net Weight	2.60 kg
Gross Weight	4.0 kg
Power Supply	85-264 V AC, 47-63 Hz, max 10 W
Power Connector	IEC, with fuse holder (1A anti-surge)
Talkback Channels	6 balanced outputs, 1 balanced input (DC signalling)
Talkback Input Gain Range	-28 dB to +9 dB (rear preset)
Microphone Type	Built-in electret or external (XLR), selectable via rear switch
Microphone Gain Range	53 dB to 74 dB (rear preset)
External Input 1	Balanced stereo line level on 9-pin D-sub
External Input 2	Unbalanced stereo (phono and 9-pin D-sub)
Monitor Speaker	1 W mono, internal
Headphone Output	6.35 mm jack, 150 mW into 32-600 Ω
Front Panel Controls	Power LED, volume, EXT1/EXT2 select, 6 talkback buttons, built-in mic
Rear Panel Connectors	Headphone jack, mic select, mic gain, talkback gain, EXT2 phono, EXT inputs & mute (9-pin D-sub), talkback I/O (15-pin D-sub), fuse, IEC
Configuration Jumpers	Internal: muting/mixing of external inputs during talkback, local/external talkback
Compatibility	Sonifex S2 mixer, other DC-signalling talkback systems
Safety & Compliance	CE, WEEE, RoHS, 12-month warranty
Cleaning	Wipe with soft dry cloth; no liquids
User Serviceable Parts	None; refer to qualified service personnel

Frequently Asked Questions - TB-6R Sonifex

How do I connect multiple TB-6R units together for more than 6 talkback points?

The TB-6R can be daisy-chained using the 15-pin D-sub talkback input/outputs. Each unit supports up to 6 talkback destinations; linking units allows communication between multiple locations (up to 7 units total). Use balanced audio cabling with DC signalling.

Can I use an external microphone instead of the built-in electret?

Yes. Connect a gooseneck or other dynamic/condenser microphone to the XLR input on the top panel. Then set the rear panel 'Mic Select' switch to the depressed (down) position to select the external mic. Adjust the Mic Level preset pot for desired gain.

How do I adjust the talkback input level?

On the rear panel, locate the 'Talkback Level' preset pot. Use a jeweller's screwdriver to adjust the gain from -28 dB to +9 dB. This controls the level of incoming talkback signals before they reach the speaker or headphones.

How can I mute the speaker remotely?

On the 9-pin external inputs D-sub connector, link pin 9 (mute control) to pin 5 (ground) to activate remote mute. This is useful in live mic areas to prevent feedback.

Can I use the TB-6R with a mixer’s talkback system?

Yes. By changing internal jumpers (J3, J4, J5) on the TB-6R, you can route the mixer’s talkback input/output via the 9-pin external inputs connector. This allows the intercom to function purely as a monitor selector while the mixer handles talkback audio. See the manual section on 'Local/External Talkback'.

What is the power consumption and fuse rating?

The TB-6R operates on 85-264 V AC, 47-63 Hz, with a maximum power consumption of 10 W. It uses a 1A anti-surge fuse located in the IEC power inlet.

Why does my talkback switch not latch when headphones are not plugged in?

The unit is designed so that talkback switches only latch when headphones are inserted. Without headphones, the switches operate in momentary mode only. This prevents accidental sustained talkback when using only the speaker.

How do I configure external inputs to mute during talkback?

Set the internal jumper J1 over pins 1 & 2 (fitted) to mute external inputs when talkback is active. Remove J1 to mix external inputs with talkback. See the internal jumper layout diagram in the manual.

What is the difference between TB-6D and TB-6R?

The TB-6D is a desktop free-standing unit, while the TB-6R is a 19-inch rack-mounted version (2U). Both have identical features and controls.

Can the TB-6R be used with other brand talkback systems?

Yes, because it uses DC signalling (ground lift) which is common in professional intercom systems. However, compatibility should be verified by testing. The TB-6R also integrates directly with Sonifex S2 mixers.

USER MANUAL TB-6R Sonifex

Collage of industrial control equipment including a T-6R device, a 5000 MHz spectrometer, and a Station Number (SOMFES) with visible ports and cables against a blue abstract background.

Abstract circular design with concentric curved lines, no text or symbols present

Station Master &

Talkback Intercoms

User Handbook

SONIFEX

This handbook covers the following product stock codes:

SM-24 Station Master for 2 studios (PPM and VU)

SM-44 Station Master for 4 studios (PPM and VU)

SM2 Add on card to upgrade from an SM24 to SM44

TB-6D Talkback Intercom 6 Way, desktop free standing

TB-6R Talkback Intercom 6 Way, 19 inch rack mounted

TB-SD Talkback Intercom Station Master, desktop free standing

TB-SR Talkback Intercom Station Master, 19 inch rack mounted

Revision 2.04 February 2020

©Sonifex Ltd, 2000-20

All Rights Reserved

Sonifex Ltd, 61, Station Road, Irthlingborough,

Northants, NN9 5QE, England.

Tel: [phone]

Fax: [phone]

Email : [e-mail] or [e-mail]

Web : http://www.sonifex.co.uk

Information in this document is subject to change without notice and does not represent a commitment on the part of Sonifex Ltd. Sonifex Ltd shall not be liable for any loss or damage whatsoever arising from the use of information or any error contained in this manual.

No part of this manual may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or information storage and retrieval systems, for any purpose other than the purchaser's personal use, without the express written permission of Sonifex Ltd.

Unless otherwise noted, all names of companies, products and persons contained herein are part of a completely fictitious adaptation and are designed solely to document the use of Sonifex products.

Warranty & Safety Information i

Warranty and Liability i

Returning the Warranty Card iii

Unpacking the Station Master/Talkback Intercom iii

Safety of Mains Operated Equipment iv

Fuse Rating iv

Power Cable and Connection iv

WEEE & RoHS Directives - Sonifex Statement v

Reporting Faults vi

1 Station Master Introduction 1

Introduction 1

Studio Switching 1

Delay Control 1

Monitoring 2

Audio Distribution 2

Talkback 2

Logging 2

Power Failure 2

Installation Notes 2

Atmosphere 2

Electromagnetic Radiation 2

Connectors and Cabling 3

XLR 3 Pin Connectors 3

1/4" 'A' Gauge Stereo Jack Plugs 3

D-Type Connectors 4

2 Operation 5

Configuration Flowchart 5

Studio Feeds, Transmission Outputs and Logging Outputs 6

Studio Feeds 6

Transmission Outputs 6

Logging Outputs 6

Logging Off-Air instead of Pre-Transmission 6

Monitoring 7

Monitoring Options 8

Enabling Talkback Over the Monitors 8

Mixing or Ducking the Normal Monitor Output During Talkback 9

Fixing the Monitor Output Level for the Phono Connectors 9

Offer and Accept Switching 10

Talkback 11

Delay and Dump Control 13

External Inputs 13

Routing Of External Inputs 13

Altering the External Input Levels 14

3 Connection Details 15

Audio Connections 15

Audio In/Out 1 - 4 16

Studio Controls 17

Controls In/Out 1 & 2 17

Controls In/Out 3 & 4 18

Transmission Outputs 19

Logging Outputs 19

Balanced Logging Outputs 19

Unbalanced Logging Outputs 19

Other Connectors 20

Mains Power 20

Delay/Dump Control 20

External Inputs 21

Monitor Output 22

Monitor Insert 22

Speaker Output 22

Talkback Microphone Input 22

5 Talkback Introduction 26

TB-6D & TB-6R 6 Way Talkback Intercom Overview 27

Example Application For TB-6D & TB-6R 28

TB-SD & TB-SR Station Master Talkback Intercom Overview 29

Example Application For TB-SD & TB-SR 29

Talkback Intercom Benefits 30

Station Master Features 31

Station Master Talkback Operation and Connections 32

6 TB-6D & TB-6R 6 Way Talkback Intercom Configuration & Controls 34

Front Panel Control Details 34

Power LED Indicator 35

Level Control for Monitor Loudspeaker and Headphones 35

External Select Switch 1 35

External Select Switch 2 35

Talkback Switches 35

Built in Electret Microphone 35

Monitor Loudspeaker 35

External Microphone 35

Rear Panel Control Details 36

Headphone Output 36

Mic Select 37

Adjusting the Microphone Gain Level 37

Adjusting the Talkback Gain Level 37

External Input 2 37

External Inputs & Mute Control 37

Talkback Input/Outputs 38

Fuse Holder 38

Mains Input 38

Internal Jumper Configuration 39

Summary of Jumper Settings for the Talkback Unit 39

External Input Muting/Mixing 40

Local/External Talkback 40

TB6 Interconnection Wiring Diagram 42

7 TB-SD & TB-SR Station Master Talkback Intercom Configuration & Controls 43

Front Panel Control Details 43

Power LED Indicator 44

Level Control for Monitor Loudspeaker and Headphones 44

External Select Switch 1 44

External Select Switch 2 44

Talkback Switches 44

Built in Electret Microphone 44

Monitor Loudspeaker 44

External Microphone 44

Rear Panel Control Details 45

Headphone Output 45

Mic Select 46

Adjusting the Microphone Gain Level 46

Adjusting the Talkback Gain Level 46

External Input 2 46

External Inputs & Mute Control 46

Station Master Remotes 47

Fuse Holder 47

Mains Input 47

Internal Jumper Configuration 48

Summary of Jumper Settings for the Talkback Unit 48

External Input Muting/Mixing 49

Local/External Talkback 49

8 Talkback Intercom Technical Specification 51

Audio & Power Specification 51

Physical Specification

52

Figures

Fig 1-1: XLR-3 Connectors. 3

Fig 1-2: ¼" Jack Connectors 3

Fig 1-3: D-Type Connectors. 4

Fig 2-1: Station Master Block Diagram. 5

Fig 2-2 : Monitor Section of the Front Panel. 7

Fig 2-3: Station Master Viewed From Above Showing Jumper Positioning. 8

Fig 2-4: Station Master Offer & Accept Status. 10

Fig 2-5 : Offer & Accept Switches for Studio 1. 10

Fig 2-6: Front Panel Talkback Switches & Mic Input. 12

Fig 5-1: TB-6D Talkback Intercom 6 Way Desktop & TB-SD Talkback Intercom Station Master Desktop. 26

Fig 5-2: TB-6R Talkback Intercom 6 Way Rack & TB-SR Talkback Intercom Station Master Rack. 26

Fig 5-3: Example Application For TB-6D & TB-6R. 28

Fig 5-4: Example Application For TB-SD & TB-SR. 29

Fig 5-5: Talkback Intercom System Block Diagram. 33

Fig 6-1: TB-6D Front Panel. 34

Fig 6-2: TB-6R Front Panel. 34

Fig 6-3: TB-6D Rear Panel. 36

Fig 6-4: TB-6R Rear Panel. 36

Fig 6-5: TB-6D & TB-6R Board Layout. 39

Fig 6-6: Connecting The Talkback Intercom To The Sonifex S2 Mixer Output Module (S2-OMC). 41

Fig 6-7: Interconnection Wiring Diagram 42

Fig 7-1: Front Panel Controls for TB-SD. 43

Fig 7-2: Front Panel Controls for TB-SR. 43

Fig 7-3: TB-SD Rear Panel. 45

Fig 7-4: TB-SR Rear Panel. 45

Fig 7-5: TB-SD & TB-SR Board Layout. 48

Fig 7-6: Connecting The Talkback Intercom To The Sonifex S2 Mixer Output Module (S2-OMC). 50

Warranty & Safety Information

Warranty and Liability

Important: the purchaser is advised to read this clause

(a) The Company agrees to repair or (at its discretion) replace Goods which are found to be defective (fair wear and tear excepted) and which are returned to the Company within 12 months of the date of despatch provided that each of the following are satisfied:

(i) notification of any defect is given to the Company immediately upon its becoming apparent to the Purchaser;
(ii) the Goods have only been operated under normal operating conditions and have only been subject to normal use (and in particular the Goods must have been correctly connected and must not have been subject to high voltage or to ionising radiation and must not have been used contrary to the Company's technical recommendations);
(iii) the Goods are returned to the Company's premises at the Purchaser's expense;
(iv) any Goods or parts of Goods replaced shall become the property of the Company;
(v) no work whatsoever (other than normal and proper maintenance) has been carried out to the Goods or any part of the Goods without the Company's prior written consent;
(vi) the defect has not arisen from a design made, furnished or specified by the Purchaser;
(vii) the Goods have been assembled or incorporated into other goods only in accordance with any instructions issued by the Company;
(viii) the defect has not arisen from a design modified by the Purchaser;
(ix) the defect has not arisen from an item manufactured by a person other than the Company. In respect of any item manufactured by a person other than the Company, the Purchaser shall only be entitled to the benefit of any warranty or guarantee provided by such manufacturer to the Company.

(b) In respect of computer software supplied by the Company the Company does not warrant that the use of the software will be uninterrupted or error free.
(c) The Company accepts liability:

(i) for death or personal injury to the extent that it results from the negligence of the Company, its employees (whilst in the course of their employment) or its agents (in the course of the agency);
(ii) for any breach by the Company of any statutory undertaking as to title, quiet possession and freedom from encumbrance.

(d) Subject to conditions (a) and (c) from the time of despatch of the Goods from the Company's premises the Purchaser shall be responsible for any defect in the Goods or loss, damage, nuisance or interference whatsoever consequential economic or otherwise or wastage of material resulting from or caused by or to the Goods. In particular the Company shall not be liable for any loss of profits or other economic losses. The Company accordingly excludes all liability for the same.

(e) At the request and expense of the Purchaser the Company will test the Goods to ascertain performance levels and provide a report of the results of that test. The report will be accurate at the time of the test, to the best of the belief and knowledge of the Company, and the Company accepts no liability in respect of its accuracy beyond that set out in Condition (a).

(f) Subject to Condition (e) no representation, condition, warranty or other term, express or implied (by statute or otherwise) is given by the Company that the Goods are of any particular quality or standard or will enable the Purchaser to attain any particular performance or result, or will be suitable for any particular purpose or use under specific conditions or will provide any particular capacity, notwithstanding that the requirement for such performance, result or capacity or that such particular purpose or conditions may have been known (or ought to have been known) to the Company, its employees or agents.

(g) (i) To the extent that the Company is held legally liable to the Purchaser for any single breach of contract, tort, representation or other act or default, the Company's liability for the same shall not exceed the Price of the Goods.

(ii) The restriction of liability in Condition (g)(i) shall not apply to any liability accepted by the Seller in Condition (c).

(h) Where the Goods are sold under a consumer transaction (as defined by the Consumer Transactions (Restrictions on Statements) Order 1976) the statutory rights of the Purchaser are not affected by these Conditions of Sale.

Returning the Warranty Card

In order to register the date of purchase so that we can keep you informed of any design improvements or modifications, it is important to complete the warranty registration document that is enclosed and return it to Sonifex Ltd in the UK, or register online at www.sonifex.co.uk/register

For your own records you should write down the serial number (which can be found at the rear of the product.

Serial Number

Unpacking the Station Master/Talkback Intercom

Each product is shipped in protective packaging and should be inspected for damage before use. Where an item is found to have transit damage, notify your supplier immediately with all the relevant details of the shipment. Packing materials should be kept for inspection and also for if the product needs to be returned.

Safety of Mains Operated Equipment

CE This equipment has been designed to meet the safety regulations currently advised in the country of purchase and it conforms to the safety regulations specified by use of the CE Mark.

The power supply is rated to 95 - 265VAC at 47 - 63Hz with a fuse of 2A.

Warning: There are no user serviceably parts inside the machine. If you should ever need to look inside the unit, always disconnect the mains supply before removing the equipment covers.

Fuse Rating

The product is supplied with a single fuse in the live conducting path of the power-in feed at the power supply. For reasons of safety it is important that the correct rating and type of fuse is used. Incorrectly rated fuses could present a possible fire hazard, under equipment fault conditions.

Power Cable and Connection

An IEC power connector is supplied with the product, which has a moulded plug attached – this is a legal requirement. If no moulded plug has been supplied with your product, please contact your supplier, because an IEC connector is always supplied from the Sonifex factory.

If for any reason, you need to use the product with a different power cable, you should use the following wiring guidelines

Wire Colour Connection

Green, or green and yellow Earth (E)

Blue, or Black Neutral (N)

Brown, or Red Live (L)

WEEE & RoHS Directives - Sonifex Statement

The Waste Electrical and Electronic Equipment (WEEE) Directive was agreed on 13 February 2003, along with the related Directive 2002/95/EC on Restrictions of the use of certain Hazardous Substances in electrical and electronic equipment (RoHS).

The Waste Electrical and Electronic Equipment Directive (WEEE) aims to minimise the impacts of electrical and electronic equipment on the environment during their life times and when they become waste. It applies to a huge spectrum of products. It encourages and sets criteria for the collection, treatment, recycling and recovery of waste electrical and electronic equipment. All products manufactured by Sonifex Ltd have the WEEE directive label placed on the case. It gives a contact for individuals who are unsure about the correct procedure when the product has reached its “end of use”.

Sonifex Ltd will be happy to give you information about local organisations that can reprocess the products, or alternatively all products that have reached “end of use” can be returned to Sonifex and will be reprocessed correctly free of charge.

Sonifex Ltd has phased out the use of certain hazardous substances identified in the European Union's Restriction of Hazardous Substances (RoHS) directive. The RoHS directive limits the use of certain hazardous substances currently used in EEE manufacture, including lead, mercury, cadmium, hexavalent chromium, and halide-containing compounds PBB (polybrominated biphenyl) and PBDE (polybrominated diphenyl ether). Elimination of these substances will result in more environmentally friendly recycling of electronic equipment. For the products which Sonifex manufacture, the main area where products were affected was in the use of lead for manufacturing and assembling electronics circuit boards.

Sonifex Ltd practices lead-free (LF) manufacturing processes. LF solder is used on the surface-mount PCB manufacturing processes and for hand soldering. The printed circuit boards (PCBs) used are either gold plated, or immersion tin plated, both of which use no lead. Historically the PCBs were hot air solder levelled (HASL) PCBs which used tin/lead based solder.

The manufacturing processes include the assembly of purchased components from various sources. Product is offered as RoHS compliant, or LF, only after sufficient evidence is received from the component manufacturers that their components are RoHS compliant. Sonifex Ltd relies solely on the distributor, or manufacturer, of the components for identification of RoHS compliance. Thus whilst every effort is made to ensure compliance, Sonifex Ltd makes no warranty, or certification, or declaration of compliance concerning said components.

Sonifex Ltd defines "Lead Free" as pertaining to any product, which has been manufactured by Sonifex Ltd using components which have been declared by the manufacturers as "Lead Free". All statements by Sonifex Ltd of RoHS compliance are based on component manufacturer documentation.

Reporting Faults

Although this Sonifex product is manufactured to the highest standards, it is possible that minor faults may appear in the equipment over its normal lifetime. If you find any problems with the product, please contact your Sonifex distributor, or contact Sonifex directly at the following address, or fax with a copy of this completed sheet:

To : From:
Sonifex Ltd, Name
61, Station Road, Position
Irthlingborough, Company
Northants. Address
NN9 5QE, UK
Tel : [phone] Tel
Fax : [phone] Fax
Email : [e-mail] Email

For the Serial No. of your machine, see the back panel of the unit.

Serial No.

Please describe the error in as much detail as possible (for example what you were doing when the problem occurred, what actually happened, etc)

Description of Error

Also, if you have any suggestions for additions or upgrades to the unit, we would like to hear what they are:

Additions that I Would Like to See

1 Station Master Introduction

Introduction

Station Master is an addition to the Sonifex range of professional audio products designed for building radio stations on a budget. It combines all the black boxes required for audio distribution, studio switching, talkback and monitoring for up to 4 studios into a single package. The Station Master has a number of benefits:

• Saves money - combining several features into one unit gives significant cost savings over purchasing the discrete parts that Station Master replaces, without any compromise on quality.
  • Easy to install - single unit simplifies installation.
• Requires less space - Station Master is a 3U high 19" single rackmount unit which replaces up to 11U rackspace that discrete components can occupy.
• Reliability - If power to the Station Master fails, it keeps the output routing as set and remembers this state, providing continuity on restoration of power.

Studio Switching

Station Master accepts stereo audio feeds from up to 4 studios, switching them individually to transmission using offer and accept operation. The output of the current 'on-air' studio is distributed to the other studios via a dedicated bus, avoiding the need for multiple studio distribution links.

The output of the Station Master is provided as a stereo pair or a mono feed of the stereo source. The studio switching is achieved using latching relays and therefore retains its switch status in the event of power-failure.

Delay Control

A profanity delay can be controlled by the Station Master allowing you to install just one delay unit that can be shared by your studios and used by the studio currently on air.

1

STATION MASTER INTRODUCTION

Station Master

Monitoring

The Station Master is fitted with either a pair of true PPM meters, or VU meters, for monitoring up to 8 stereo sources. These sources consist of the connected studios and four external sources such as news feeds or off air receivers. The audio can be monitored via headphones or output through a power amplifier capable of driving 10W into 8 speakers. There are also two 1/4" jack insert points for using the Station Master to monitor from a jack-field.

Audio Distribution

Station Master distributes the 4 incoming stereo signals to each of the connected studios without the need for external distribution amplifiers. These signals, such as off-air receivers, news feeds and outside broadcasts, can be professional balanced inputs or at domestic unbalanced line levels. The gain of the incoming stereo signals can be adjusted from the front panel. Distribution gain is controlled by a preset potentiometer.

Talkback

The Station Master's talkback system acts as the master station for talkback with 4 satellite systems. These can either be the connected studios or other locations such as a record library or engineering workshop. Individual satellites can talk to each other or broadcast to all stations.

Logging

To allow for logging of broadcasts the Station Master has a stereo balanced output for professional logging equipment, together with 3 sets of phono unbalanced outputs for connection to domestic VCR equipment.

Power Failure

In the event of a power failure to the Station Master, it will continue to route the current on-air studio to the stereo transmission output. Also, when power is re-applied to the Station Master, all switching, including the offer and accept switching, will instantly re-initialise to the configuration when power was lost. This means that your on-air studio can continue transmitting, even if power to the Station Master has failed.

Installation Notes

Atmosphere

The Station Master should be installed in an area which is not subject to excessive heat or cold. Also, you should avoid installing it in atmospheric conditions which are dusty, smoky or dirty, or where there is moisture or vibration.

Do not use liquids to clean the front of the Station Master - wiping with a soft, dry cloth is advised.

Electromagnetic Radiation

Note that there can be a degradation of the audio quality if the Station Master is used near to strong sources of electromagnetic radiation. Strong sources include video monitors, and mains cabling.

Connectors and Cabling

Many of the problems associated with installing and maintaining studio equipment are due to the use of poor cables or faulty connections. It is recommended that, wherever possible, prewired cables are purchased from recommended manufacturers. If you need bespoke cables making, please ensure that the work is carried out by a qualified engineer.

The main types of connectors used with the Station Master are the following :

XLR 3 Pin Connectors

The following diagram shows the pin details for the 3 pin XLR sockets and plugs :

Fig 1-1: XLR-3 Connectors.

1/4" 'A' Gauge Stereo Jack Plugs

1/4" 'A' Gauge Stereo Jack Plugs can be connected as follows :

Fig 1-2: ¼" Jack Connectors

1

STATION MASTER INTRODUCTION

Station Master

D-Type Connectors

Three different D-Type connectors are used on the Station Master. A 9 pin plug is used for the Delay/Dump Control. A 25 pin plug is used for the Audio I/O and a 25 pin socket for the Control I/O connector.

Fig 1-3: D-Type Connectors.

2 Operation

Configuration Flowchart

graph TD
    subgraph External Inputs
        A1["External Input 1"] --> B1["To Studio 1"]
        A2["External Input 2"] --> B2["To Studio 2"]
        A3["External Input 3"] --> B3["To Studio 3"]
        A4["External Input 4"] --> B4["To Studio 4"]
    end

    subgraph Main Studio Feeds
        C1["Main Feed From Studio 1"] --> D1["Last Studio To Offer Switch"]
        C2["Main Feed From Studio 2"] --> D2["Studio Feed Bus"]
        C3["Main Feed From Studio 3"] --> D3["Studio On Air"]
        C4["Main Feed From Studio 4"] --> D4["Studio On Offer"]
    end

    subgraph Offer & Accept Switches
        E1["Studio 1 Offer Switch"] --> F1["Offer And Accept Circuit"]
        E2["Studio 1 Accept Switch"] --> F2["Studio 1 On Air"]
        E3["(Studios 2,3 & 4 are identical to 1)"]
    end

    subgraph Delay & Dump Switches
        G1["Studio 1 Dump Switch"] --> H1["Dump And Delay Circuit"]
        G2["Studio 1 Delay Switch"] --> H2["Delay Unit (Not Included)"]
        G3["(Studios 2,3 & 4 are identical to 1)"]
    end

    subgraph Talkback Control
        I1["Talkback Mic Input"] --> J1["Level"]
        I2["Talkback From Studio 1"] --> J2["Talkback To Studio 1"]
        I3["Talkback From Studio 2"] --> J3["Talkback To Studio 2"]
        I4["Talkback From Studio 3"] --> J4["Talkback To Studio 3"]
        I5["Talkback From Studio 4"] --> J5["Talkback To Studio 4"]
    end

    subgraph Talkback Switching Matrix
        K1["Talkback Switching Matrix"] --> L1["Talkback To Studio 1"]
        K2["Talkback To Studio 2"]
        K3["Talkback To Studio 3"]
        K4["Talkback To Studio 4"]
        K5["Talkback To Studio 5"]
    end

    subgraph Monitor Outputs
        M1["Monitor Bus"] --> N1["PPM or VU Meter Driven"]
        N1 --> O1["Monitor Headphones"]
        O1 --> P1["Jumper Selectable"]
        P1 --> Q1["Speaker Output"]
        Q1 --> R1["Level"]
        R1 --> S1["Monitor Output"]

    end

    subgraph Transmission Outputs
        T1["Balanced Stereo Transmission Output"]
        T2["Balanced Mono Transmission Output"]
        T3["Logging Outputs"]
        T4["Balanced Stereo Logging Output"]
        T5["Balanced Mono Logging Output"]
        T6["Unbalanced Logging Output"]
        T7["Unbalanced Logging Output"]
        T8["Unbalanced Logging Output"]
    end

    subgraph Jumper Selectable
        U1["Jumper Selectable"]
        U2["Jumper Selectable"]
    end

    style External Inputs fill:#f9f,stroke:#333
    style Main Studio Feeds fill:#ccf,stroke:#333
    style Offer & Accept Switches fill:#cfc,stroke:#333
    style Delay & Dump Switches fill:#fcc,stroke:#333
    style Talkback Control fill:#cff,stroke:#333

Fig 2-1: Station Master Block Diagram.

Studio Feeds, Transmission Outputs and Logging Outputs

Studio Feeds

Station Master takes an audio feed from each connected studio and routes them to the transmission and logging outputs. It uses the offer and accept switching to know which output should be switched to air - as soon as a studio accepts the offer made by the current on-air studio, the output is switched to the accepting studio. The following connections should be made :

The audio feed, from the master output of the mixing desk which you are using in each studio, should be connected to the 25 pin D-type "AUDIO IN/OUT" plug connector, on pins 1, 2, 14 and 15 (marked TRX left/right phase/non-phase). Pin 13 can be used as the screen for these connections. This is the audio feed from the studio to the Station Master.

Once all the studios are connected, you will need to connect the Offer and Accept switching (see the Section marked "Offer and Accept Switching") to ensure that the correct studio is switched to the transmission path.

Transmission Outputs

Depending on whether you are transmitting a mono or stereo signal, you can use either the mono, or stereo balanced XLR-3 transmission outputs to connect the Station Master to a limiter or processor before being sent to the transmitter.

Logging Outputs

Which logging output you use depends on what type of logging equipment you have installed in your radio station. If you are using a balanced "professional" piece of logging equipment, such as the Sonifex Net-Log audio logger, or a balanced PC based recorder, then the balanced XLR-3 outputs should be connected. There are separate stereo and mono outputs.

If you are using "consumer" logging equipment, such as domestic DVD-R recorders, then there are three phono outputs which can be connected. Three outputs have been provided so that three DVD-R's can be used to record longer durations.

Logging Off-Air instead of Pre-Transmission

You can also choose whether to log the transmission output (before it is sent to the transmitter), or whether to log the External Input 1, which could be defined as an off-air receiver, so that you can log what is actually broadcast. On the main motherboard SM-MB-02, check the following jumpers:

Jumper Set Over Pins Effect
JP5	1 & 2	The left logging output comes from the transmission path.
	2 & 3	The left logging output comes from External Input 1.
JP6	1 & 2	The right logging output comes from the transmission path.
	2 & 3	The right logging output comes from External Input 1.

Note : Items in bold are set as default when shipped.

Set the jumpers over pins 2 & 3 if you want to connect an off-air receiver to External Input 1. See Fig 2-3 for placement of the jumpers on the motherboard.

Monitoring

Fig 2-2: Monitor Section of the Front Panel.

• Front panel monitoring is carried out using the eight MONITOR SELECT buttons on the front of the unit. These buttons control which input is sent to the monitor speaker outputs, the monitor outputs, the headphones and the meters.
• The MONITOR INSERT 1/4" jack sockets can be used to monitor left and right signals from a jackfield - they over-ride the MONITOR SELECT selection.
• The "MONITOR LEVEL" volume control alters the level of the output from the monitor speakers and the monitor output.
• The "PHONES LEVEL" volume control alters the level of the output from the headphones.

2

Inside the Station Master there are a number of jumpers that can be altered to change the way that the monitor function operates :

Fig 2-3: Station Master Viewed From Above Showing Jumper Positioning.

Enabling Talkback Over the Monitors

The output of the monitors is normally whatever is selected from the "MONITOR SELECT" buttons on the front panel. You can also have inter-studio talkback sent to the monitors by doing the following. On the Monitor and External Input PCB (SM-ML-01) set jumpers JP2 and JP3 over pins 2 & 3 (see Fig 2-3):

Jumper Set Over Pins Effect
JP2	1 & 2	Monitors (left channel) only output the monitor selection.
	2 & 3	Monitors (left channel) output talkback and the monitor selection.
JP3	1 & 2	Monitors (right channel) only output the monitor selection.
	2 & 3	Monitors (right channel) output talkback and the monitor selection.

Note : Items in bold are set as default when shipped.

Mixing or Ducking the Normal Monitor Output During Talkback

If the talkback is enabled over the monitors, as above, normally the monitor selection output is ducked while the talkback is output. You can also have the talkback mixed with the monitor selection output by setting jumper JP1 on the monitor and external input PCB (SM-ML-01) (see Fig 2-3):

Jumper Set Over Pins Effect
JP1	1 & 2Off	If talkback is enabled, it is mixed with the monitor selection.If talkback is enabled, the monitor selection is ducked while the talkback is output.

Note : Items in bold are set as default when shipped.

Fixing the Monitor Output Level for the Phono Connectors

The monitor output level for the phono connectors can be made either fixed, or affected by the volume control on the front panel of the Station Master. On the main motherboard SMMB-02, check the following jumpers (see Fig 2-3):

Jumper Set Over Pins Effect
JP1	1 & 2	Monitor left output on the phonos is at a fixed level.
	2 & 3	Monitor left output on the phonos can be altered by volume control.
JP2	1 & 2	Monitor right output on the phonos is at a fixed level.
	2 & 3	Monitor right output on the phonos can be altered by volume control.

Note : Items in bold are set as default when shipped.

2

Offer and Accept Switching

The Station Master can control the Offer and Accept switching for up to four connected studios. This switching also controls which studio output is sent to the transmission and logging outputs and which studio has control of the delay/dump switching.

Fig 2-4: Station Master Offer & Accept Status.

The way that offer and accept switching works is that each studio has an Offer and an Accept switch which is routed back to the Station Master. The Station Master has an audio feed to each studio called the "Last Studio to Offer" which should be routed to an input of each studio mixer (Station Master takes this from the transmission output of the current Accepted studio which is already routed to the Station Master).

When a studio is on-air, it has accepted the request to transmit and it's Accept Lamp is illuminated to indicate this. When a studio is reaching the end of its broadcast, the DJ presses the Offer button and the Offer buttons in all connected studios will illuminate to indicate that the transmission is ready to be passed to another studio.

To Accept the offer, a studio must bring up the "Last Studio to Offer" on the mixer (ensuring that the levels are the same as for the outgoing studio - this should be completed beforehand by an engineer), and press the Accept button. The transmission path is then immediately taken from the accepting studio and its' Accept light illuminates. All the Offer lights in the other studios are simultaneously extinguished.

The front panel of the Station Master shows the status of the studios with a LED indication. When the "STUDIO ON OFFER" LED is illuminated, it means that the studio indicated is on offer.

So, the connections for each studio can be summarised as :

graph LR
    A["×"] --> B["Studio 1 O fferSwitch"]
    C["×"] --> D["Studio 1 AcceptSwitch"]
    B --> E["Station Master"]
    D --> E
    E --> F["AudiofromLastStudio t o O ffer to a m ixingdeskinput"]

Fig 2-5: Offer & Accept Switches for Studio 1.

Connect the "Last Studio to Offer" balanced audio connection from the Station Master to each studio using pins 3, 4, 16 and 17 of the "Audio In/Out" connector. Pin 13 can be used as a screen.

For each studio, connect Offer and Accept switches to pins 2 and 3 respectively of the "Controls In/Out" connectors. Pins 15 and 16 can be used to power the Offer and Accept lamps respectively.

Note : A standard Offer and Accept switch panel can be ordered which operates with the Sonifex S2 mixer (S2-MTBS) and which also has Delay/Dump controls as well as an Obit indicator.

Talkback

Talkback refers to the standard method of communication between studios - each studio has a row of switch buttons, each one of which connects to another studio when pressed, and routes the presenter audio to it. Station Master can route and control the talkback between up to 4 studios and the Station Master itself (i.e. 5 talkback points). Each studio has the ability to have a row of five switch buttons so that the presenter can talk to the other three studios, the Station Master, or all studios, including the Station Master. So, for each studio, you'll need to make the following connections :

Connect the talkback switches to pins 6, 7, 8, 9, and 10 of the "Controls In/Out" connectors. Pins 19, 20, 21 and 22 can be used to power the lamps for the switches. (When the T/B Switch All button is pressed, all four lamps should be illuminated).

Note : The talkback connection details are slightly different for each studio - ensure that you are connecting to the correct studio.

Connect the unbalanced audio input and output signals, together with the T/B control output to the studio :

• The T/B audio input (pin 23 of the "Controls In/Out" connector) should be connected to the talkback output of the mixing desk in the studio.
• The T/B audio output (pin 12 of the "Controls In/Out" connector) should be connected to the talkback input of the mixing desk in the studio.
• The T/B control signal (pin 13 of the "Controls In/Out" connector) should be routed to the talkback control input of the mixing desk. When one of the talkback buttons is pressed in a different studio, the talkback control signal closes to indicate to the mixing desk that a talkback signal is being sent to it. The mixing desk is usually configured to mix the talkback with the presenter's headphones, so that the presenter can hear the talkback being sent from another studio.

On the front of the Station Master are a set of switches for communication with the other studios. There is also a TALKBACK LEVEL control for altering the level of the talkback received from other studios to the in-built speaker.

2

A microphone can be plugged directly into the front of the Station Master for when sending talkback to other studios. We recommend the use of a standard STUB, or goose-neck, microphone. The level of the microphone can be set by adjusting the MIC LEVEL potentiometer using a small flatbladed jeweller's screwdriver.

To operate the talkback, simply press and hold the button for the studio that you want to talk to for the duration of your conversation.

Fig 2-6: Front Panel Talkback Switches & Mic Input.

Note : A standard talkback panel is available for insertion into the Sonifex Sovereign mixer which has five talkback switches for communication with 3 other studios, all studios or the Station Master unit.

Delay and Dump Control

Station Master can be used to control a single profanity delay unit from the multiple studios connected to it. Please note that Station Master does not actually contain a profanity delay.

The unit has two relay controls, Delay and Dump, which should be connected to the profanity unit from the 9 pin D-type on the rear of the Station Master.

Each studio should then be connected to a Dump and Delay switch mounted on the mixing console. For each studio, connect Dump and Delay switches to pins 4 and 5 respectively of the "Controls In/Out" connectors. Pins 17 and 18 can be used to power the Dump and Delay lamps respectively.

In the following description of operation, it is assumed that a sampling profanity delay unit is used which uses digital audio techniques to build up a delay of several seconds which can be dumped all at once, or in several steps.

When a presenter enters a studio and wants to operate in delay, he should ensure that the Delay lamp is illuminated. If it isn't, then the Delay button should be pressed. When the Delay button is pressed in a studio, a permanent contact closure is enabled between the Station Master and the delay unit and the Delay lamp illuminates. This indicates that the delay unit has been primed (however, it may be some time before the delay has actually been built up to the full quoted duration - see your delay unit's technical literature). Pressing the Delay button again will take the delay unit out of operation

If the presenter wants to dump the current on-air audio (for example, if a telephone caller starts swearing), he should press the Dump button. When the Dump button is pressed, a 0.5 second pulse is sent to the Dump input of the profanity delay, so that the current broadcast is discarded (the amount of audio discarded is controlled by your profanity delay). The Dump lamp illuminates for 0.5 seconds while this is happening. The presenter is then immediately live as if the telephone caller had never sworn!

Note : The switch panel which operates with the Sonifex S2 mixer (S2-MTBS) has Delay/ Dump switch controls built into it.

External Inputs

Routing Of External Inputs

The Station Master can accept four stereo balanced inputs which can be distributed to all of the four studios independently. To connect the external sources, use the following connectors :

Audio inputs to the Station Master should be wired to the "External Inputs" connector on the far left of the unit (looking at it from the rear). Phase, non-phase and screen connections are provided for both left and right signals of each input.

Audio outputs to each studio are found on Pins 5 - 12 and Pins 18 - 25 on each of the Audio In/Out 1 - 4 connectors. They all share a common screen on Pin 13.

2

The levels for each input can be altered by adjusting the small potentiometers hidden beneath the holes on the front panel, underneath the "MONITOR SELECT" buttons for EXT 1 - EXT 4 (See Fig 2-2). You'll need a small flat-blade jeweller's screw driver to turn the potentiometers.

The input range for the input level can be adjusted between +5dB and -16dB.

3 Connection Details

Section 1.3 contains information on standard connector wiring for the XLR's, jacks and D-Type connectors found on the Station Master.

Audio Connections

The 25 pin D-Type male (plug) audio connectors marked "AUDIO IN/OUT 1 - 4" are mounted vertically on the rear panel below the "CONTROLS IN/OUT 1 - 4" connectors. All of them have the same connection details.

Audio In/Out 1 - 4

Pin No.	Audio In/Out 1 - 4
1	TRX Left Phase input
2	TRX Right Phase input
3	Last Studio to Offer Left Phase output
4	Last Studio to Offer Right Phase output
5	External 1 Left Phase output
6	External 1 Right Phase output
7	External 2 Left Phase output
8	External 2 Right Phase output
9	External 3 Left Phase output
10	External 3 Right Phase output
11	External 4 Left Phase output
12	External 4 Right Phase output
13	0 Volts Analog (Screen)
14	TRX Left Non-Phase input
15	TRX Right Non-Phase input
16	Last Studio to Offer Left Non-Phase output
17	Last Studio to Offer Right Non-Phase output
18	External 1 Left Non-Phase output
19	External 1 Right Non-Phase output
20	External 2 Left Non-Phase output
21	External 2 Right Non-Phase output
22	External 3 Left Non-Phase output
23	External 3 Right Non-Phase output
24	External 4 Left Non-Phase output
25	External 4 Right Non-Phase output
Case (Mounted on chassis)

Studio Controls

The Studio Control connectors are 25 pin D-Type female (socket) connectors mounted vertically below the studio numbers 1 to 4 (1 to 2 for the SM24 model).

Note : the talkback connections for each studio's control connector are different, so please ensure that you are careful when using the details below.

Controls In/Out 1 & 2

Pins 2 - 10 are momentary make to 0V common Pin 14

Pins 15 - 22 are all open collector to 0V, current sink outputs

Pin No.	Controls In/Out 1 Controls In/Out 2
1 Volts	+15V Volts +15V
2 Offer Switch Offer Switch
3 Accept Switch Accept Switch
4 Delay Switch Delay Switch
5 Dump Switch Dump Switch
6 T/B	Switch to studio 2 T/B Switch to studio 1
7 T/B	Switch to studio 3 T/B Switch to studio 3
8 T/B	Switch to studio 4 T/B Switch to studio 4
9 T/B	Switch to Station Master T/B Switch to Station Master
10 T/B	Switch All T/B Switch All
11 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
12 T/B	Audio output to Studio 1 T/B Audio output to Studio 2
13 T/B	Control output to Studio 1 T/B Control output to Studio 2
14	0 Volts common	0 Volts common
15 Offer Lamp		Offer Lamp
16 Accept Lamp		Accept Lamp
17 Delay Lamp		Delay Lamp
18 Dump Lamp		Dump Lamp
19 T/B	Lamp for studio 2 switch T/B Lamp for studio 1 switch
20 T/B	Lamp for studio 3 switch T/B Lamp for studio 3 switch
21 T/B	Lamp for studio 4 switch T/B Lamp for studio 4 switch
22 T/B	Lamp for Station Master switch T/B Lamp for Station Master switch
23 T/B	Audio input from Studio 1 T/B Audio input from Studio 2
24 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
25 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
Case	(Mounted on chassis) N/C	N/C (Mounted on chassis)

Controls In/Out 3 & 4

Pins 2 - 10 are momentary make to 0V common Pin 14

Pins 15 - 22 are all open collector to 0V, current sink outputs

Pin No.	Controls In/Out 3 Controls In/Out 4
1 Volts	+15V Volts +15V
2 Offer Switch Offer Switch
3 Accept Switch Accept Switch
4 Delay Switch Delay Switch
5 Dump Switch Dump Switch
6 T/B	Switch to studio 1 T/B Switch to studio 1
7 T/B	Switch to studio 2 T/B Switch to studio 2
8 T/B	Switch to studio 4 T/B Switch to studio 3
9 T/B	Switch to Station Master T/B Switch to Station Master
10 T/B	Switch All T/B Switch All
11 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
12 T/B	Audio output to Studio 3 T/B Audio output to Studio 4
13 T/B	Control output to Studio 3 T/B Control output to Studio 4
14	0 Volts common	0 Volts common
15 Offer Lamp	Offer Lamp
16 Accept Lamp	Accept Lamp
17 Delay Lamp	Delay Lamp
18 Dump Lamp	Dump Lamp
19 T/B	Lamp for studio 1 switch T/B Lamp for studio 1 switch
20 T/B	Lamp for studio 2 switch T/B Lamp for studio 2 switch
21 T/B	Lamp for studio 4 switch T/B Lamp for studio 3 switch
22 T/B	Lamp for Station Master switch T/B Lamp for Station Master switch
23 T/B	Audio input from Studio 3 T/B Audio input from Studio 4
24 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
25 0 Volts Analog (Audio Common) 0 Volts Analog (Audio Common)
Case	(Mounted on chassis)	(Mounted on chassis)

Transmission Outputs

There are three XLR 3 pin plugs used for the electronically balanced transmission outputs. The transmission output is simultaneously fed to both the stereo (LR) and mono outputs. Usually, these outputs will be connected to a processor/limiter before the signal is sent to the transmitter. The connectors have the following pin details:

Pin No. Transmission Outputs
1 Screen
2 Phase
3 Non-phase

Logging Outputs

Balanced Logging Outputs

There are three XLR 3 pin plugs used for the electronically balanced logging outputs. The station output is simultaneously fed to both the stereo (LR) and mono outputs, so that a professional logging machine such as the Sonifex Net-Log can be used to log the station output. The connectors have the following pin details:

Pin No. Balanced Logging Outputs
1 Screen
2 Phase
3 Non-phase

Unbalanced Logging Outputs

The unbalanced phono logging outputs are useful for connecting to domestic logging machines, such as to DVD recorders. Three outputs have been provided so that three DVD-Rs can be used to record a longer duration. The connections are :

Pin No. Unbalanced Logging Outputs
Tip Phase
Ring Non-phase

3

STATION MASTER CONNECTION DETAILS

Station Master

Other Connectors

Mains Power

IEC Connector

Delay/Dump Control

The 9 Pin D-Type male (plug) connector provides the outputs for controlling a profanity delay :

Pin No. Delay/Dump Control
1 Ground
2 N/C
3 Delay relay contact, normally closed
4 Dump relay, common contact
5 Dump relay contact, normally open
6 N/C
7 Delay relay, common contact
8 Delay relay contact, normally open
9 Dump relay contact, normally closed

External Inputs

The 25 pin D-Type female (socket) connector provides the stereo balanced inputs for the four external sources, with the following pins used :

Pin No. External Inputs

1 Left phase input EXT 1

2 Left chassis ( screen ) input EXT 1

3 Right non-phase input EXT 1

4 Left phase input EXT 2

5 Left chassis ( screen ) input EXT 2

6 Right non-phase input EXT 2

7 Left phase input EXT 3

8 Left chassis ( screen ) input EXT 3

9 Right non-phase input EXT 3

10 Left phase input EXT 4

11 Left chassis ( screen ) input EXT 4

12 Right non-phase input EXT 4

13 N/C

14 Left non-phase input EXT 1

15 Right phase input EXT 1

16 Right chassis ( screen ) input EXT 1

17 Left non-phase input EXT 2

18 Right phase input EXT 2

19 Right chassis ( screen ) input EXT 2

20 Left non-phase input EXT 3

21 Right phase input EXT 3

22 Right chassis ( screen ) input EXT 3

23 Left non-phase input EXT 4

24 Right phase input EXT 4

25 Right chassis ( screen ) input EXT 4

3

STATION MASTER CONNECTION DETAILS

Station Master

Monitor Output

The monitor output uses a pair of unbalanced phono connectors for the left and right signal. These should be used if you want to distribute the transmission output through the radio station by connecting these to a power amplifier. The connections are :

Pin No. Monitor Output
Tip Phase
Ring Non-phase

Monitor Insert

The left and right monitor insert connectors are 14 " (6.3mm) jack sockets with the following connections :

Pin No. Monitor Insert
Tip Phase
Ring Non-phase
Sleeve Screen

Speaker Output

The speaker outputs allow you to connect a pair of speakers directly to the Station Master, for use, for example, in the station foyer. The connectors are quick connect spring loaded lever terminals with two holes each for left and right pairs of speaker wires.

Talkback Microphone Input

The talkback microphone input on the front of the Station Master uses an XLR-3 female balanced connector. It has the following connections:

Pin No.	Talkback Microphone Input
1 Screen
2 Phase
3 Non-phase

We recommend the use of a stub-neck microphone such as those made by Canford Audio (STUB MIC NC, no 53-099).

Headphones

The headphone socket on the front of the Station Master is 14 " (6.3mm) jack socket suitable for driving 600 ohm stereo headphones.

Pin No. Headphones

Tip Left Out

Ring Right Out

Sleeve Common

4

STATION MASTER TECHNICAL SPECIFICATION

Station Master

4 Station Master Technical Specification

Inputs/Outputs

Transmission Outputs: Balanced feed-through of transmission inputs via relay contacts.

Mono Output: <75Ω electronically balanced.

Stereo Line Inputs: >20kΩ electronically balanced.

Stereo Line Outputs: <75Ω electronically balanced.

Professional Logging Outputs: <75Ω electronically balanced.

Domestic Logging Outputs: <75Ω unbalanced.

Monitor Speaker Outputs: 10 Watts into 8Ω.

Talkback Mic Input: >1.5kΩ electronically balanced.

Talkback Line Inputs: >10kΩ unbalanced.

Switch Inputs: Momentary closure to common.

Headphone Output: Drives 600 ohm headphones.

Lamp Outputs: Open Collector reference to common, sink 40mA Voltage for lamps is supplied.

Frequency Response

Mic Input: 40Hz to 20kHz at -1dB, +0dB.

Line Inputs: 20Hz to 20kHz at -0.5dB, +0dB.

Noise (20Hz to 20kHz)

Mic Input E.I.N.: -128dB with 200Ω source.

Stereo Line Inputs: -96dB (ref. +8dB)

Connections Summary

For more detail of the connections, please refer to Section 3.

Transmission Outputs: XLR 3 pin male (Balanced).

Mono Output: XLR 3 pin male (Balanced).

Stereo Line External Inputs: 25 pin D-Type plug male.

Studio Line Inputs/Outputs: 25 pin D-Type plug male.

Studio Talkback & Controls: 25 pin D-Type socket female.

Talkback Mic Input: XLR 3 pin female (Balanced).

Professional Logging Outputs: XLR 3 pin male (Balanced).

Domestic Logging Outputs: Phono sockets.

Monitor Speaker Outputs: Quick connect spring loaded lever terminals.

Headphones: 14 " Stereo jack socket.

Physical Specification

Dimensions: 13.5cm (3U)(H)×48.3cm (19" Rack)(w) × 30cm (D)

Weight: 9.15 kgs

Equipment Type

SM24-VU: Station Master with switching and talkback for 2 studios, VU meters.

SM44-VU: Station Master with switching and talkback for 4 studios, VU meters.

SM24-PPM: Station Master with switching and talkback for 2 studios, PPM meters.

SM44-PPM: Station Master with switching and talkback for 4 studios, PPM meters.

SM2

Add on cards to upgrade from an SM24 to an SM44.

5

TALKBACK INTERCOM INTRODUCTION

Close-up of a white electronic device with a black screen and a metallic blade, partially obscured by a purple background (no visible text or symbols)

5 Talkback Introduction

Talkback refers to the standard method of communication between broadcast studios. Each studio has either a desktop, a rack-mount, or mixer-mounted intercom, usually containing a row of switch buttons. Each switch buttons connects to another studio when pressed, and routes the presenter audio to it.

There are 4 products in the Sonifex Talkback Intercom range :

TB-6D 6 Way Talkback Intercom, desktop free standing

TB-6R 6 Way Talkback Intercom, 19" rack mounted

TB-SD Station Master Talkback Intercom, desktop free standing

TB-SR Station Master Talkback Intercom, 19" rack mounted

The TB-6D and TB-6R are general talkback interfaces which can be connected together to form a talkback system. The TB-SD and TB-SR are talkback units which only operate when connected to the Sonifex Station Master studio switcher.

Fig 5-1: TB-6D Talkback Intercom 6 Way Desktop & TB-SD Talkback Intercom Station Master Desktop.

Front panel of an electronic device with ports and a knob (no visible text or symbols)

Front panel of a computer interface with buttons and ports (no readable text or symbols)

Front view of a beige electronic device rear panel with ports and connectors (no visible text or symbols)

Front view of a Siemens 3.02 microcontroller with ports and indicator lights (no visible text or labels)

Fig 5-2: TB-6R Talkback Intercom 6 Way Rack & TB-SR Talkback Intercom Station Master Rack.

TB-6D & TB-6R 6 Way Talkback Intercom Overview

The TB-6D and TB-6R are used for general talkback between studios and use DC signalling, also known as ground lifting or ground signalling, to communicate with each other. These units can be installed in various locations throughout a studio complex and linked to one another, with each unit being able to talkback to up to 6 others connected together. Most other talkback systems in general operation also use DC signalling, so you should be able to add these units into an existing installation.

The TB-6D and TB-6R are identical in operation, with the TB-6D used for desktop operation and the TB-6R available as a 2U rack-mount, for use for example, in a central apparatus room or central technical area.

Up to 7 locations or studios can communicate with each other. On each panel, there are 6 front panel buttons for talkback selection and 2 for external inputs. While a button is pressed, the button lights up and the talkback is active to that location.

The buttons work with both a momentary and latched operation. If you simply press the button, talkback will be on and can be cancelled by pressing the button again. If you press and hold the button, the selection is cancelled when released. So, if you wanted to listen to an external input, such as the radio station feed, or off-air monitor, you could simply press the EXT 1 button. If you press a talkback button when the external input buttons are also pressed, the external inputs can be either muted or mixed, depending on the setting of an internal jumper.

The talkback outputs and input are balanced signals on a 15-way male 'D' type plug and the talkback input can be adjusted from -28dB to 9dB using a rear panel preset pot.

You can speak to the separate locations using the onboard front-panel electret mic or there is a separate external mic input on 3 pin XLR female, into which you can plug a suitable gooseneck microphone. There is a rear panel switch to select between the electret and separate input mic. The mic input gain range is adjustable via a rear panel preset pot between 74dB and 53dB.

The unit can monitor two external sources. The EXT 1 input is a balanced stereo input on a rear panel 9 pin D-type socket. The EXT 2 input is an unbalanced stereo input on the 9 pin D-type socket as well as dual phono sockets. EXT 1 is useful for monitoring a distributed signal, such as a radio tuner off-air feed, or an outside source routed from an ISDN codec. EXT 2 is useful for monitoring a local source, such as a portable minidisc/flashcard recorder/player, or the unbalanced soundcard output from a PC editing/playback package.

If you already use a mixer which has a talkback input and output, or continuous talkback output, or just a line level output which you want to use, by changing internal jumpers the intercom can be configured to use these connections instead of the on-board microphone and speaker/headphones. For example, if you have a mic channel on a mixer assigned to talkback and the presenter is using headphones for monitoring the mixer talkback, the Talkback Intercom can be used purely for talkback switching and for monitoring external inputs.

Close-up of a white electronic device with a black circular button and a metallic blade, partially obscured by a light overlay (no visible text or symbols)

5 TALKBACK INTERCOM INTRODUCTION

Close-up of a white electronic device with a black screen and a metallic blade, no visible text or symbols.

For monitoring, you can use either the built-in 1W loudspeaker, or headphones on 6.35mm unbalanced stereo jack. The headphones provide 150mW into 32-600Ω headphones. When the headphones are used, the speaker is automatically muted. Additionally, the monitor speaker can be muted via a remote contact on the 9 pin D-type External Input connector, for example, when used in an area with live microphones. Both monitor and headphone levels are fully adjustable between 60dB and 9dB using the front panel volume control.

Example Application For TB-6D & TB-6R

A typical application would be to distribute talkback and audio feeds around a radio or TV studio complex, as in this diagram.

graph TD
    subgraph RECEPTION_AREA
        A["TB-6D"] -->|Talkback EXT 1| B["Talkback"]
        B --> C["EXT 1"]
    end

    subgraph MAIN_ON_AIR_STUDIO_1
        D["TB-6D or TB-6R"] --> E["Talkback"]
        E --> F["EXT 1"]
    end

    subgraph NEWS_AREA
        G["TB-6D"] --> H["Portable MD/Flashcard Recorder/Player"]
        H --> I["Talkback EXT 1"]
        I --> J["EXT 2"]
    end

    subgraph PRODUCTION_STUDIO_ON_AIR_STUDIO_2
        K["TB-6D or TB-6R"] --> L["Talkback"]
        L --> M["EXT 1"]
    end

    subgraph SALES_AREA
        N["PC Soundcard"] --> O["Talkback EXT 1"]
        O --> P["EXT 2"]
    end

    subgraph CENTRAL_TECHNICAL_AREA
        Q["TB-6R"] --> R["Off-Air Receiver"]
        R --> S["Outside Sourcing, eg. codec"]
        S --> T["Talkback"]
        T --> U["EXT 1"]
        U --> V["EXT 2"]
    end

    RECEPTION_AREA -->|Talkback EXT 1| MAIN_ON_AIR_STUDIO_1
    NEWS_AREA -->|Talkback EXT 1| MAIN_ON_AIR_STUDIO_1
    SALES_AREA -->|Talkback EXT 1| MAIN_ON_AIR_STUDIO_1

Fig 5-3: Example Application For TB-6D & TB-6R.

The TB-6D and TB-6R units are daisy-chained from together from location to location and the radio station output from an off-air receiver is distributed on input EXT 1 of each unit. The EXT 2 input could be used in the news or sales area for monitoring local sources such as a PC audio output. Linking the studios in this way allows all locations to talk to each other together with the ability to monitor 2 external feeds, with independent control of monitor muting and headphone/speaker levels.

TB-SD & TB-SR Station Master Talkback Intercom Overview

These units are used for interfacing with the Sonifex Station Master studio switcher and are similar to the 6 way talkback intercoms, except that the talkback routing and switching (DC signalling) is handled by the Station Master.

All of the features regarding level control, use of the microphone, speaker, headphones, volume control and external inputs are the same as for the TB-6D and TB-6R intercoms. However, the TB-SD and TB-SR can be used to communicate with up to 4 other locations (including the Station Master), or all of the locations by pressing the "ALL" button.

Whereas the TB-6D and TB-6R have talkback outputs and input on a 15-way male 'D' type plug, the TB-SD and TB-SR have instead a remotes socket consisting of a 25-way female 'D' type. This contains switch and indicator controls for the 4 talkback buttons together with power and talkback input/output/control lines to and from the Station Master.

Example Application For TB-SD & TB-SR

Using the Station Master as the core of a complete studio air-switching, distribution and talkback system, up to 4 studios can be connected using the TB-SD and TB-SR. A typical application would be to distribute talkback and audio feeds around a small radio station, as in this diagram.

graph TD
    A["RECEPTION-AREA"] -->|Talkback EXT 1| B(CENTRAL TECHNICAL AREA)
    C["NEWS AREA/INPUT BOOTH"] -->|Talkback EXT 2| B
    D["MAIN ON-AIR STUDIO 1"] -->|Talkback EXT 1| B
    E["PRODUCTION STUDIO/ON-AIR STUDIO 2"] -->|Talkback EXT 1| B
    B --> F["Station Master"]
    F --> G["Off-Air Receiver"]
    G --> H["TB-SD or TB-SR"]
    B --> I["TB-SD"]

Fig 5-4: Example Application For TB-SD & TB-SR.

Close-up of a white electronic device with a screen and antenna, no visible text or symbols

5 TALKBACK INTERCOM INTRODUCTION

Close-up of a white electronic device with a transparent fan and control buttons, no visible text or symbols.

The TB-SD and TB-SR intercoms are connected to the Station Master in a star pattern, with the Station Master as the central hub and unbalanced point-to-point links from it to each location. This setup could also be used for controlling on-air switching and for distribution of the external inputs to the other locations.

Talkback Intercom Benefits

• Provide talkback for up to 7 locations (for TB-6D and TB-6R).
  • Brightly lit push-to-talk buttons.
  • Momentary or latched buttons.
  • Built-in electret microphone, with input for external microphone.
  • Monitoring of 2 external inputs, e.g. for off-air receiver.
  • Auto muting, or mix, of external inputs.
• Integrates with Sonifex S2 mixer and is compatible with other talkback systems.

Following are details on how the Station Master functions.

Station Master Features

Two of the talkback intercoms link to the Sonifex Station Master. This is a 3U rack-mount Sonifex product which combines into a single package all the black boxes required for audio distribution, studio switching, talkback and monitoring for up to 4 studios.

Studio Switching - Station Master accepts stereo audio feeds from up to 4 studios, switching them individually to transmission using offer and accept operation. The output of the current 'on-air' studio is distributed to the other studios via a dedicated bus, avoiding the need for multiple studio distribution links. The output of the Station Master is provided as a stereo pair or a mono feed of the stereo source. The studio switching is achieved using latching relays and therefore retains its switch status in the event of power-failure.

Delay Control - A profanity delay can be controlled by the Station Master allowing you to install just one delay unit that can be shared by your studios and used by the studio currently on air.

Monitoring - The Station Master is fitted with either a pair of true PPM meters, or VU meters, for monitoring up to 8 stereo sources. These sources consist of the connected studios and four external sources such as news feeds or off air receivers. The audio can be monitored via headphones or output through a power amplifier capable of driving 10W into 8Ω speakers. There are also two 14 " jack insert points for using the Station Master to monitor from a jack-field.

Audio Distribution - Station Master distributes the 4 incoming stereo signals to each of the connected studios without the need for external distribution amplifiers. These signals, such as off-air receivers, news feeds and outside broadcasts, can be professional balanced inputs or at domestic unbalanced line levels. The gain of the incoming stereo signals can be adjusted from the front panel. Distribution gain is controlled by a preset potentiometer.

Talkback - The Station Master's talkback system acts as the master station for talkback with 4 satellite systems. These can either be the connected studios or other locations such as a record library or engineering workshop. Individual satellites can talk to each other or broadcast to all stations.

Logging - To allow for logging of broadcasts the Station Master has a stereo balanced output for professional logging equipment, together with 3 sets of phono unbalanced outputs for connection to domestic VCR equipment.

Power Failure - In the event of a power failure to the Station Master, it will continue to route the current on-air studio to the stereo transmission output. Also, when power is re-applied to the Station Master, all switching, including the offer and accept switching, will instantly re-initialise to the configuration when power was lost. This means that your on-air studio can continue transmitting, even if power to the Station Master has failed.

Close-up of a white electronic device with a black circular button and a metallic blade, partially obscured by a light overlay (no visible text or symbols)

5 TALKBACK INTERCOM INTRODUCTION

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

Station Master Talkback Operation and Connections

Station Master can route and control the talkback between up to 4 studios and the Station Master itself (i.e. 5 talkback points). Each studio has the ability to have a row of five switch buttons so that the presenter can talk to the other three studios, the Station Master, or all studios, including the Station Master. So, for each studio, you'll need to make the following connections:

Connect the talkback switches to pins 6, 7, 8, 9, and 10 of the "Controls In/Out" connectors. Pins 19, 20, 21 and 22 can be used to power the lamps for the switches. (When the T/B Switch All button is pressed, all four lamps should be illuminated).

Note : The talkback connection details are slightly different for each studio - ensure that you are connecting to the correct studio.

Connect the unbalanced audio input and output signals, together with the T/B control output to the studio :

• The T/B audio input (pin 23 of the "Controls In/Out" connector) should be connected to the talkback output of the mixing desk in the studio.
• The T/B audio output (pin 12 of the "Controls In/Out" connector) should be connected to the talkback input of the mixing desk in the studio.
• The T/B control signal (pin 13 of the "Controls In/Out" connector) should be routed to the talkback control input of the mixing desk. When one of the talkback buttons is pressed in a different studio, the talkback control signal closes to indicate to the mixing desk that a talkback signal is being sent to it. The mixing desk is usually configured to mix the talkback with the presenter's headphones, so that the presenter can hear the talkback being sent from another studio.

On the front of the Station Master are a set of switches for communication with the other studios. There is also a TALKBACK LEVEL control for altering the level of the talkback received from other studios to the in-built speaker.

A microphone can be plugged directly into the front of the Station Master for when sending talkback to other studios. We recommend the use of a standard STUB, or goose-neck, microphone. The level of the microphone can be set by adjusting the MIC LEVEL potentiometer using a small flat-bladed jeweller's screwdriver.

To operate the talkback, simply press and hold the button for the studio that you want to talk to for the duration of your conversation.

Note : A standard talkback panel is available for insertion into the Sonifex S2 mixer which has five talkback switches for communication with 3 other studios, all studios or the Station Master unit.

graph TD
    A["1 2 3 4 5 6"] --> B["TB-6D & TB-SR TALKBACK SWITCHES"]
    C["1 2 3 4 ALL"] --> B
    D["TB-6D & TB-SR"] --> E["STATION MASTER REMOTES"]
    F["TALKBACK OUTPUTS/INPUT"] --> G["TRX"]
    H["TRX"] --> I["TRX"]
    J["External INPUTS"] --> K["MUTE"]
    L["VOLUME CONTROL"] --> M["SWITCHING/ROUTING"]
    N["EXT INPUTS MUTE CONTROL"] --> M
    O["T/BACK IN"] --> P["T/BACK CTRL"]
    Q["T/BACK GAIN"] --> P
    R["J1"] --> S["EXT1 EXT2"]
    T["J3"] --> U["T/BACK OUT"]
    V["AGC"] --> W["MIC GAIN"]
    X["EXT MIC"] --> Y["EXCTRET MIC"]
    Z["LETTLE"] --> AA["OUT"]
    AB["LETTLE"] --> AC["OUT"]
    AD["LETTLE"] --> AE["OUT"]
    AF["LETTLE"] --> AG["OUT"]
    AH["LETTLE"] --> AI["OUT"]
    AJ["LETTLE"] --> AK["OUT"]
    AL["LETTLE"] --> AM["OUT"]
    AN["LETTLE"] --> AO["OUT"]

Illustration of a stylized house with decorative elements and floating bubbles (no text or symbols)

TALBACK INTERFACE INTRODUCTION
Fig 5-5: Talkback Intercom System Block Diagram.

6

TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a screen and antenna, no visible text or symbols

6 TB-6D & TB-6R 6 Way Talkback Intercom Configuration & Controls

Front Panel Control Details

Information about all of the connections and controls located on the front of the TB-6D units. Monitor External

Fig 6-1: TB-6D Front Panel.

Power LED Indicator

The power LED indicates that the equipment is powered and operational when illuminated.

Level Control for Monitor Loudspeaker and Headphones

This will alter the output level of either the top mounted monitor loudspeaker or the rear mounted headphone output. Plugging in the headphones mutes the loudspeaker output.

External Select Switch 1

This selects and routes external input 1 to the headphones or loudspeaker.

External Select Switch 2

This selects and routes external input 2 to the headphones or loudspeaker.

Talkback Switches

While a button is pressed, the switch is illuminated and the talkback is active to that location. The buttons work with both a momentary and latched operation (* see below). If held down, the selection is cancelled when released, otherwise the button is alternate action. When talkback is active, depending on the setting of Jumper 1, the external inputs can be either muted or mixed.

* When headphones are not inserted, it's not possible to latch the function of talkback switches 1-6. The latch function will function as normal when headphones are inserted. Similarly if the latched function is used with headphones inserted and they are then removed, the unit will default back to non-latched operation.

Built in Electret Microphone

The built in microphone, fitted under the front panel, is used unless the external mic is selected on the rear panel.

Monitor Loudspeaker

There is a 1W mono speaker output to hear talkback and external monitoring. The talkback level is adjustable via the pot on the rear panel. The external input level is set internally. The talkback and EXT 1 and EXT 2 output levels can be adjusted using the front panel level control. The speaker can be muted via a remote on the external input connector when used in an area with live microphones.

External Microphone

The external microphone input is an XLR 3 pin connector on the top panel which allows the fitment of a gooseneck microphone or other standard microphone. Selection for the microphone input type is made on the back panel.

Pin 1: Screen.

Pin 2: Phase.

Pin 3: Non-phase

Close-up of a white electronic device with a black circular button and a metallic blade, partially obscured by a light overlay (no visible text or symbols)

6

TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a transparent fan and control buttons (no visible text or symbols)

TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

Rear Panel Control Details

Information about all of the connections and controls located on the rear of the TB-6D units.

Fig 6-3: TB-6D Rear Panel.

Headphone Output

This is a 6.35mm unbalanced stereo headphone jack providing a stereo audio output, capable of driving 150mW into 32-600Ω headphones. Plugging in the headphones disables the loudspeaker output.

Ring: Right

Tip : Left

Sleeve : Screen

Mic Select

This push-button switch selects the mic input :Switch depressed (down) - External mic selectedSwitch not depressed (up) - Internal mic selected

Adjusting the Microphone Gain Level

The Mic Level Preset Pot controls the level of the mic input signal. Use a jeweller's screwdriver to adjust the gain between 74dB and 53dB.

Adjusting the Talkback Gain Level

The Talkback Level Preset Pot controls the level of the talkback input signal. Use a jeweller's screwdriver to adjust the gain between -28dB and 9dB.

External Input 2

This is a dual phono socket, stereo unbalanced at domestic level in parallel with the 9 way female 'D' type socket. These inputs are not used when pins 4 & 8 on the external inputs connector are configured for talkback.

Inner: Phase

Outer: Screen

External Inputs & Mute Control

This is a 9-way female 'D' type socket used for accepting external inputs and the mute signal. External input 1 is a balanced analogue stereo line level input with an impedance of >40kΩ. Pins 4 & 8 are dual purpose and configured by the internal jumpers. When the pins are used as external input 2, or as talkback input/output they accept an unbalanced analogue stereo domestic level input with an impedance of >30kΩ.

If you already use a mixer which has a talkback input and output, or continuous talkback output, or just a line level output which you want to use, by changing internal jumpers the intercom can be configured to use these connections instead of the on-board microphone and speaker/headphones. For example, if you have a mic channel on a mixer assigned to talkback and the presenter is using headphones for monitoring the mixer talkback, the Talkback Intercom can be used purely for switching and monitoring external inputs. See the later section on “Local/External Talkback” for information on how to do this.

The connector pin-out is as follows;

Pin 1: Talkback control output (active low)
Pin 2: Input 1 left phase
Pin 3: Input 1 right phase
Pin 4: Input 2 left OR Talkback in phase (see jumper settings)
Pin 5: Ground
Pin 6: Input 1 left non-phase
Pin 7: Input 1 right non-phase
Pin 8: Input 2 right OR Talkback out phase (see jumper settings)
Pin 9: Mute control (link to pin 5 for speaker mute)

Close-up of a white electronic device with a black circular button and a metallic blade, partially obscured by a light overlay (no visible text or symbols)

6 TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

Talkback Input/Outputs

These use a 15-way male 'D' type plug for the six balanced talkback outputs and one balanced talkback input, which all use DC signalling. These can interface with other Sonifex S2 mixer talkback or intercom units as well as talkback panels in some other mixers, or dedicated talkback systems.

The connector pin-out is as follows;

Pin 1: Talkback 1 out phase.

Pin 2: Talkback 2 out phase.

Pin 3: Talkback 3 out phase.

Pin 4: Talkback 4 out phase.

Pin 5: Talkback 5 out phase.

Pin 6: Talkback 6 out phase.

Pin 7: Talkback in phase.

Pin 8: Ground.

Pin 9: Talkback 1 out non-phase.

Pin 10: Talkback 2 out non-phase.

Pin 11: Talkback 3 out non-phase.

Pin 12: Talkback 4 out non-phase.

Pin 13: Talkback 5 out non-phase.

Pin 14: Talkback 6 out non-phase.

Pin 15: Talkback in non-phase.

Fuse Holder

Fitted with a single 1 amp anti-surge fuse.

Mains Input

The power supply is connected via an IEC Connector (85V - 264V, 47-63Hz AC operation).

Internal Jumper Configuration

The talkback intercom can be configured in a number of ways depending on the way in which the jumpers are set. The standard options are;

• Mix or mute external inputs when talkback is active.
• Select local or external (via external inputs connector) talkback.

Summary of Jumper Settings for the Talkback Unit

Jumper	Set over Pins	Effect
J1	1 & 2None	External inputs are muted when talkback is activeExternal inputs are mixed when talkback is active
J2 - Reserved
J3	1 & 2None	Set when local talkback is usedSet when external talkback is used
J4	1 & 22 & 3	Pin 4 on External Inputs connector is external input 2 leftPin 4 on External Inputs connector is talkback input
J5	1 & 22 & 3	Pin 8 on External Inputs connector is external input 2 rightPin 8 on External Inputs connector is talkback output

Note: Options in bold are set as default when shipped.

Fig 6-5: TB-6D & TB-6R Board Layout.

6

TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

External Input Muting/Mixing

When the talkback is active, the external inputs can be either muted or mixed to the outputs depending on the jumper settings. With J1 fitted the external inputs are muted when talkback is active. With J1 not fitted the external inputs are mixed with the talkback when active.

Local/External Talkback

The talkback can be either local or external. When J4 is fitted over pins 1 & 2, pin 4 on the external inputs remote connector is configured as external input 2 left. When J4 is fitted over pins 2 & 3, pin 4 on the external inputs remote connector is configured as the talkback input.

In this case, talkback input means the talkback input to the internal system, i.e. it is an actual output on the 9 pin D-type connector, which could be the talkback input to the Sonifex S2 mixer control room monitor channel.

When J5 is fitted over pins 1 & 2, pin 8 on the external inputs remote connector is configured as external input 2 right. When J5 is fitted over pins 2 & 3, pin 8 on the external inputs remote connector is configured as the talkback output.

In this case, the talkback output is to the internal system, but on the connector appears as a talkback input, e.g. when the talkback output comes from another source other than the built in microphone or external microphone connector. This could be, for example, the talkback output from the Sonifex S2 mixer control room monitor channel, or a continuous talkback output from any other mixer.

In this case J3 must also be not fitted, so that the internal mic, or connected mic are not used. If J3 is fitted, the mic will be mixed over the incoming talkback signal.

Below is an example of using the external talkback by connecting the unit to an S2 mixer via the control room monitor module. The following connections are made to the module via the external inputs connector on the rear panel:

Pin 1: Connect to "Ring" on the talkback input jack.

Pin 2: As required.

Pin 3: As required.

Pin 4: Connect to "Tip" on the talkback input jack.

Pin 5: Ground (connect to screens).

Pin 6: As required.

Pin 7: As required.

Pin 8: Connect to "Tip" on the talkback output jack.

Pin 9: As required.

graph TD
    A["TB-SD & SR"] --> B["STATION MASTER REMOTES"]
    B --> C["FITTED OVER PINS 2 & 3"]
    C --> D["S2 MIXER"]
    D --> E["S2-CMC CONTROL ROOM MONITOR"]
    D --> F["TALKBACK INPUT"]
    D --> G["TALKBACK OUTPUT"]
    H["TB-6D & 6R"] --> I["TALKBACK OUTPUTS/INPUT"]
    I --> J["TRX"]
    J --> K["External INPUTS"]
    K --> L["J3 NOT FITTED"]
    M["TRX"] --> N["External INPUTS"]
    O["External INPUTS"] --> P["PINS 1 & 4"]
    P --> Q["S2 MIXER"]

Fig 6-6: Connecting The Talkback Intercom To The Sonifex S2 Mixer Output Module (S2-OMC).

Close-up of a white electronic device with a transparent screen and control buttons, no visible text or symbols.

Close-up of a white electronic device with a black circular top and a metallic blade, partially visible against a purple background (no text or symbols)

TB-6D & TB-6R TALKBACK INTERCOM CONFIGURATION & CONTROLS

TB6 Interconnection Wiring Diagram Example Situations

This configuration applies to TB-6D, TB-6R, S2-TBS units.

If the TB-6D or TB-6R units are to be used in a live microphone situation, the mute signals (pins 5 & 9) on the external inputs connector must be connected to the relevant mic live mute controls signals.

Studio 1

Studio 2
Racks Room
News Booth
Sales Office
Reception
News Room

Fig 6-7: Interconnection Diagram.

7 TB-SD & TB-SR Station Master Talkback Intercom Configuration & Controls

Front Panel Control Details

Information about all of the connections and controls located on the front of the

TB-SD units.

Fig 7-1: Front Panel Controls for TB-SD.

Close-up of a smartphone screen with abstract UI elements and a circular icon (no readable text or symbols)

7 TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a transparent fan and control buttons, no visible text or symbols.

Power LED Indicator

The power LED indicates that the equipment is powered and operational when illuminated.

Level Control for Monitor Loudspeaker and Headphones

This will alter the output level of either the top mounted monitor loudspeaker or the rear mounted headphone output. Plugging in the headphones will disable the loudspeaker output.

External Select Switch 1

This selects and routes external input 1 to the headphones or loudspeaker.

External Select Switch 2

This selects and routes external input 2 to the headphones or loudspeaker.

Talkback Switches

While a button is pressed, the switch is illuminated and the talkback is active to that location. The "ALL" button allows talkback to all 4 of the locations. The buttons work with both a momentary and latched operation. If held down, the selection is cancelled when released, otherwise the button is alternate action. When talkback is active, depending on the setting of Jumper 1, the external inputs can be either muted or mixed.

Built in Electret Microphone

The built in microphone, fitted under the front panel, is used unless the external mic is selected on the rear panel.

Monitor Loudspeaker

There is a 1W mono speaker output to hear talkback and external monitoring. The talkback level is adjustable via the pot on the rear panel. The external input level is set internally.

The talkback and EXT 1 and EXT 2 output levels can be adjusted using the front panel level control. The speaker can be muted via a remote on the external input connector when used in an area with live microphones.

External Microphone

The external microphone input is an XLR 3 pin connector on the top panel which allows the fitment of a gooseneck microphone or other standard microphone. Selection for the microphone input type is made on the back panel.

Pin 1: Screen.

Pin 2: Phase.

Pin 3: Non-phase

Rear Panel Control Details

Information about all of the connections and controls located on the rear of the TB-SD units.

Fig 7-3: TB-SD Rear Panel.

Fig 7-4: TB-SR Rear Panel.

Headphone Output

This is a 6.35mm unbalanced stereo headphone jack providing a stereo audio output, capable of driving 150mW into 32-600Ω headphones. Plugging in the headphones disables the loudspeaker output.

Ring: Right

Tip : Left

Sleeve: Screen

Close-up of a smartphone screen with a white abstract graphic overlay (no readable text or symbols)

7 TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a transparent fan and control buttons, no visible text or symbols.

Mic Select

This push-button switch selects the mic input :

Switch depressed (down) - External mic selected

Switch not depressed (up) - Internal mic selected

Adjusting the Microphone Gain Level

The Mic Level Preset Pot controls the level of the mic input signal. Use a jeweller's screwdriver to adjust the gain between 74dB and 53dB.

Adjusting the Talkback Gain Level

The Talkback Level Preset Pot controls the level of the talkback input signal. Use a jeweller's screwdriver to adjust the gain between -28dB and 9dB.

External Input 2

This is a dual phono socket, stereo unbalanced at domestic level in parallel with the 9 way female 'D' type socket. These inputs are not used when pins 4 & 8 on the external inputs connector are configured for talkback.

Inner: Phase

Outer: Screen

External Inputs & Mute Control

This is a 9-way female 'D' type socket used for accepting external inputs and the mute signal. External input 1 is a balanced analogue stereo line level input with an impedance of >40k . Pins 4 & 8 are dual purpose and configured by the internal jumpers. When the pins are used as external input 2, or as talkback input/output they accept an unbalanced analogue stereo domestic level input with an impedance of >30k .

If you already use a mixer which has a talkback input and output, or continuous talkback output, or just a line level output which you want to use, by changing internal jumpers the intercom can be configured to use these connections instead of the on-board microphone and speaker/headphones. For example, if you have a mic channel on a mixer assigned to talkback and the presenter is using headphones for monitoring the mixer talkback, the Talkback Intercom can be used purely for switching and monitoring external inputs. See the later section on "Local/External Talkback" for information on how to do this.

The connector pin-out is as follows;

Pin 1: Talkback control output (active low)

Pin 2: External input 1 left phase

Pin 3: External input 1 right phase

Pin 4: External input 2 left OR Talkback in phase (see jumper settings)

Pin 5: 0V Analogue (Input 2 Common)

Pin 6: External input 1 left non-phase

Pin 7: External input 1 right non-phase

Pin 8: External input 2 right OR Talkback out phase (see jumper settings)

Pin 9: Mute control (link to pin 1 for speaker mute)

Station Master Remotes

This is a 25-way female 'D' type socket used for connecting to the Talkback connector on a Sonifex Station Master. The connector pin-out is as follows:

Pin 1: +15V Input from Station Master (indicator supply)

Pin 2: N/C.

Pin 3: N/C.

Pin 4: N/C.

Pin 5: N/C.

Pin 6: Talkback 1 switch.

Pin 7: Talkback 2 switch.

Pin 8: Talkback 3 switch.

Pin 9: Talkback 4 switch.

Pin 10: Talkback all switch.

Pin 11:0V Analogue (audio common).

Pin 12: Talkback input from Station Master talkback out.

Pin 13: Talkback control input.

Pin 14: 0V Analogue (switch common).

Pin 15: N/C.

Pin 16: N/C.

Pin 17: N/C.

Pin 18: N/C.

Pin 19: Talkback 1 indicator.

Pin 20: Talkback 2 indicator.

Pin 21: Talkback 3 indicator.

Pin 22: Talkback 4 indicator.

Pin 23: Talkback output to Station Master talkback input.

Pin 24: 0V Analogue (audio common).

Pin 25: 0V Analogue (audio common).

Fuse Holder

Fitted with a single 1 amp anti-surge fuse

Mains Input

The power supply is connected via an IEC Connector (85V - 264V, 47-63Hz AC operation).

Close-up of a white electronic device with a black circular button and a metallic blade, partially overlaid by a light blue background (no visible text or symbols)

7

TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a handheld device with a screen and antenna, no visible text or symbols

TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

Internal Jumper Configuration

The Talkback Intercom can be configured in a number ways depending on the way in which the jumpers are set. The standard options are;

• Mix or mute external inputs when talkback is active.
• Local or external (via external inputs connector) talkback.

Summary of Jumper Settings for the Talkback Unit

Jumper	Set over Pins	Effect
J1	1 & 2None	External inputs are muted when talkback is activeExternal inputs are mixed when talkback is active
J2 - Reserved
J3	1 & 2None	Set when local talkback is usedSet when external talkback is used
J4	1 & 22 & 3	Pin 4 on External Inputs connector is external input 2 leftPin 4 on External Inputs connector is talkback input
J5	1 & 22 & 3	Pin 8 on External Inputs connector is external input 2 rightPin 8 on External Inputs connector is talkback output

Note: Options in bold are set as default when shipped.

Fig 7-5: TB-SD & TB-SR Board Layout.

External Input Muting/Mixing

When the talkback is active the external inputs can be either muted or mixed to the outputs depending on the jumper settings. With J1 fitted the external inputs are muted when talkback is active. With J1 not fitted the external inputs are mixed with the talkback when active.

Local/External Talkback

The talkback can be either local or external. When J4 is fitted over pins 1 & 2, pin 4 on the external inputs remote connector is configured as external input 2 left. When J4 is fitted over pins 2 & 3, pin 4 on the external inputs remote connector is configured as the talkback input.

In this case, talkback input means the talkback input to the internal system, i.e. it is an actual output on the 9 pin D-type connector, which could be the talkback input to the Sonifex S2 mixer control room monitor channel.

When J5 is fitted over pins 1 & 2, pin 8 on the external inputs remote connector is configured as external input 2 right. When J5 is fitted over pins 2 & 3, pin 8 on the external inputs remote connector is configured as the talkback output.

In this case, the talkback output is to the internal system, but on the connector appears as a talkback input, e.g. when the talkback output comes from another source other than the built in microphone or external microphone connector. This could be, for example, the talkback output from the Sonifex S2 mixer control room monitor channel, or a continuous talkback output from any other mixer.

In this case J3 must also be not fitted, so that the internal mic, or connected mic are not used. If J3 is fitted, the mic will be mixed over the incoming talkback signal.

Below is an example of using the external talkback by connecting the unit to an S2 mixer via the control room monitor module. The following connections are made to the module via the external inputs connector on the rear panel:

Pin 1: Connect to "Ring" on the talkback input jack.

Pin 2: As required.

Pin 3: As required.

Pin 4: Connect to "Tip" on the talkback input jack.

Pin 5: Ground (connect to screens).

Pin 6: As required.

Pin 7: As required.

Pin 8: Connect to "Tip" on the talkback output jack.

Pin 9: As required.

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

7 TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

Close-up of a white electronic device with a transparent blade and control buttons, no visible text or symbols.

TB-SD & TB-SR STATION MASTER TALKBACK INTERCOM CONFIGURATION & CONTROLS

graph TD
    A["TB-SD & SR"] --> B["STATION MASTER REMOTES"]
    B --> C["Fitted OVER PINS 2 & 3"]
    C --> D["External INPUTS"]
    D --> E["S2 MIXER"]
    E --> F["S2-OMC CONTROL ROOM MONITOR"]
    F --> G["TALKBACK INPUT"]
    F --> H["TALKBACK OUTPUT"]
    I["TB-6D & 6R"] --> J["TALKBACK OUTPUTS/INPUT"]
    J --> K["TRX"]
    K --> L["TRX"]
    L --> M["J3 NOT FITTED"]
    M --> N["PINS 1 & 4"]
    N --> O["PINS 8"]
    O --> P["External INPUTS"]

Fig: 7-6: Connecting The Talkback Intercom To The Sonifex S2 Mixer Output Module (S2-OMC).

8 Talkback Intercom Technical Specification

Audio & Power Specification

Feature Value
Talkback Input/Outputs	15-way male ‘D’ type plug (TB-6D & TB-6R) for 6 balanced talkback outputs and 1 balance talkback input.
Talkback Input Gain Range	9dB to -28dB adjusted by rear panel preset pot.
External Inputs & Mute	9-way female ‘D’ type socket, for stereo balanced external input 1, stereo unbalanced external input 2 (or external talkback input/output), talkback control output and mute input.
External Input 2	Dual phono socket, stereo unbalanced in parallel with the 9 way female ‘D’ type socket.
External Inputs Impedance	>30kΩ (unbalanced).
	>40kΩ (balanced).
External Talkback Input Impedance	>30kΩ (unbalanced).
External Talkback Output Impedance	<80Ω (unbalanced).
External Microphone Input	3 pin female XLR socket.
Mic Input Impedance	1.5kΩ balanced.
Microphone Input Gain Range	74dB to 53dB adjusted by rear panel preset pot.
Headphone Output	6.35mm jack, unbalanced stereo capable of driving 150mW into 32-600Ω headphones.
Headphone Output Gain Range	9dB to<-60dB (off) adjusted by front panel pot.
Station Master Remotes 25-way female ‘D’ type socket (TB-SD & TB-SR).
Loudspeaker power 1W.
Mains Input Power IEC, 85V - 264V	AC, 47-63Hz, max 10W.
Fuse Holder 1A anti-surge fuse.

Close-up of a white electronic device with a black circular button and a light blue abstract background (no visible text or symbols)

Close-up of a white electronic device with a black screen and a light blue abstract graphic overlay (no readable text or symbols)

Physical Specification

Order Code	Description Height Width Depth Total				Nett Weight	Total Gross Weight
TB-6D TB-SD	Talkback intercom desk units	6.1cm 22cm	17.0cm 1.25kg 2.0kg
TB-6R TB-SR	Talkback intercom, 19" rack mounted	8.9cm (2U)	48.3cm (19" rack)	18.5cm 2.60kg 4.0kg

Close-up of a white electronic device with a propeller and control panel (no visible text or symbols)

NOTES

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

NOTES

Close-up of a white electronic device with a black circular button and a metallic blade, against a purple background (no visible text or symbols)

NOTES

SONIFEX

www.sonifex.co.uk

t:[phone]

f:[phone]

[e-mail]

Product display of SonoFEX audio equipment with control knobs and buttons (no visible text or symbols)