AEV ITB 3O2 User manual

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
1
AEV ITB 3O2
Dual Digital Telephone Hybrid

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
2
ITB 302
Guarantee
The equipment is warranted for a period of 2 years from the date of invoice (ex-works). The
warranty does not cover faults provoked by carelessness, natural causes and parts sub ect to
wear. In addition, the cost of labour and shipment is not covered. The warranty will be voided
if the equipment is mishandled.
AEV VIA DELLA TECNICA N.33 I-40050 ARGELATO BOLOGNA ITALY WWW.AEV.eu WWW. E-
MAIL: [e-mail]
Feedback
AEV welcomes your comments on our products. Your suggestions may be extremely useful to
develop new equipment and manuals and this will be of benefit to you too! Let us have your
comments on our products and we will be pleased to read them.
S e n d your information by e-mail to the following address: [e-mail], or send a letter
to the AEV SERVICE Department.
Technical Support
If you require technical support, contact AEV SERVICE giving a clear and concise account of
your specific problem. Quote the serial number of your equipment by referring to the AEV
nameplate attached to the equipment itself as this is the most important piece of information
to be provided.
Factory Service and Repairs
If problems arise while the equipment is being installed, consult this manual and check that
the
installation is being carried out properly. If the problems still cannot be solved, call the AEV
SERVICE Department for further information. If the problem is a minor one we can a telephone
call will probably suffice. If, on the other hand, the equipment is to be shipped to AEV for
service or repairs.
No repairs will be made if the cost of shipment is charged to AEV. In this case, we will not
accept the delivery.
Shipping Instruction
When shipping the equipment to AEV, use the original package in order to be certain that it will
be fully protected during handling. If you need the original package, call us for a new one.
If you ship the equipment in a different packing container, take care to provide a double
package
by interposing padding material between the two containers in order to fully protect the
equipment during shipment. The package should be marked "FRAGILE" in red.
Remember that the RMA number must be clearly visible on the package. If it is not, the
equipment will not be accepted.
SAFETY PRECAUTIONS
IMPORTANT: Carefully read this paragraph as it contains important instructions concerning
operator safety and directions regarding the installation, operation and maintenance of the
equipment.
Failure to observe the safety instructions and information given in this manual constitutes an
infringement of t e safety rules and design specifications provided for t is piece of
equipment.
Futurcom declines all responsibility if any one of the safety rules given herein is not
observed.
Futurcom declines all responsibility if the end-user resells the product.

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
3
The equipment is to be used by people capable of operating it in a trouble-free manner and it
is assumed t at t ey are aware of t e following safety rules.
• Keep this manual with the utmost care and close at hand so that it can be consulted
whenever needed
• After unpacking the equipment, check it for condition.
• Avoid banging the equipment.
• The packing material (plastic bags, polystyrene, nails, etc.) must never be left within the
reach of the children, as t ese items are potential sources of danger.
• Do not use the equipment in places where the temperature is not within the recommended
range, as specified by the manufacturer.
• Before connecting the equipment, make sure the nameplate specifications correspond to the
mains electricity supply (the nameplate is located on the equipment enclosure).
• Do not remove the sticker from the equipment as it contains important specifications and the
relevant serial number.
• To oin the equipment to the mains supply, use the power cord purchased with the
equipment.
• The equipment must be used only for the purpose it was designed for.
• Abuse or misuse of the equipment is extremely dangerous for people, pets and property.
The manufacturer declines all responsibility for damage and in ury resulting from improper
use and mis andling.
• Certain basic safety rules must be observed when using electrical equipment, in particular:
- Never touch the equipment with wet and/or damp hands or other parts of the body.
- Keep the equipment away from drops of water or sprinkling systems.
- Never use the equipment near high heat sources or explosive material.
- Do not introduce any extraneous matter into the equipment.
- Do not allow children or untrained people to use the equipment.
• Before cleaning or servicing the equipment outside, disconnect it from the supply and wait at
least 2 seconds before working on it, as recommended by current safety regulations.
• In the event of faults and/or improper operation, turn off the equipment, shut off the
electrical power and call your dealer.
covers/guards or circuit boards are to be removed.
• Blown fuses inside the power supply indicate that there may be a fault in the power supply
itself. The fuses must be replaced by qualified and authorised persons. It is advisable to call
your nearest dealer.
• Call your dealer for any repairs and be certain original spare parts are used. Failure to
observe t is rule may adversely affect t e safety level of your equipment.
• The equipment is to be connected to the mains supply and provided with adequate and
efficient earth conductors.
• The electrical wiring must be done in compliance with current electrical codes CEI 64-8
“Electrical specification for domestic buildings”.
• When installing, leave a clearance of at least 1 cm around the equipment to allow air to pass
freely.
NOTE. T is piece of equipment as been manufactured to t e ig est standards of
workmans ip. It must be used properly and serviced as recommended to ensure
long-term dependable operation.
The installation must be done in order to be able to guarantee an easy access to the cable of
feeding.
The device of dissection of the equipment is the cable of feeding, so it must be unconnected
from the equipment every time it is ecessary to do any type of maintenance.

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
4
Contents
Guarantee .......................................................... 2
Feedback............................................................ 2
Technical Support .................................................. 2
Factory Service and Repairs......................................... 2
Shipping Instruction ............................................... 2
SAFETY PRECAUTIONS ........................................... 3
Contenets .................................................... 5
PRECAUTIONS .................................................. 5
Telephone hybrids ............................................ 5
Features of AEV ITB-302 ...................................... 5
Installation ................................................. 5
General Description........................................... 6
The front panel .............................................. 6
The rear panel............................................... 6
The remote control .......................................... 7
On telephone lines........................................... 8
Connections to mixer and lines............................... 8
Hanging-on a line............................................ 8
Adjusting levels............................................. 8
Conference mode.............................................. 8
Releasing a line............................................. 8
Remote control operation of mixer ............................ 8
Expansions................................................... 8
4-wire lines................................................. 8
Technical Data............................................... 9
AUDIO LEVELS................................................. 9
INSERT....................................................... 9
HYBRID CIRCUIT .............................................. 9
4 WIRE SECTION............................................... 9
MEETING SECTION.............................................. 9
GENERAL DATA................................................. 9
Connections.................................................. 10
Connections EXPANDERS / REMOTE............................... 11
Expander 1.............................................. .....11
Remote....................................................... 11
Expander 2................................................... 11
Meeting connection ...........................................12

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
5
Telephone hybrids
A telephone hybrid is a system that is able to make an audio connection between a telephone
line and low frequency equipment. In practice this connection is by no means simple since
the characteristics of the telephone line require the equipment to employ a series of
techniques to ensure good audio quality and immunity to interference.
The bandwidth of a normal telephone line is compressed from about 100 Hz to 3-4 KHz in
order to guarantee a good reproduction of the human voice. A telephone hybrid must have a
wide frequency response in order to adapt to the quality of any line and to avoid adding
further limitations to the system. Unfortunately telephone lines are often sources of intense
disturbances, noise, crackling, fading etc. Furthermore they are often sources or conductors
of static charge and overvoltage, able to destroy circuits which have been imprudently
connected to them. Add the fact that the resistive and capacitative behaviours of line are
not uniform, and thus barely repeatable, and clearly the transmitted audio quality will vary
with time.
It is therefore necessary to take particular care in the design of line-audio interfaces in order
to avoid significant degradation of the bandwidth or re-in ection of induced interference. The
interface must also ensure complete electrical isolation between the line section and that
connecting to the audio equipment.
Another problem arises during a telephone connection between a remote correspondent
and an interviewer or DJ; the DJ’s voice will be transmitted down the telephone line and,
since the same line is used for transmission and reception, received again with a delay
with respect to the original. It will be re-amplified and looped back resulting in whistles
and Larsen effects. Usually, antilocal circuits are designed to solve this matter by
identifying those audio components which tend to enter into the loop and eliminating
only the part which re-enters. This is indispensable for Audioconferences.
The new Digital Hybrid features with an electronic echo canceller, that allows to reduce
drastically or even eliminate the feedback. In this way the diaphony is improved thanks
to the use of a DSP.
Audioconferencing allows simultaneous communication between remote correspondents that
are interconnected through telephone lines and the hybrid, which interconnects them without
introducing distortions or noise. It allows also to the DJ to participate in the conference. The
DJ, as “manager” of the conference, is able to include or exclude each correspondent from the
conference and can also speak privately to each of them for instance to prepare the interview.
Features of AEV I TB-302
AEV ITB-302 is a telephone hybrid that satisfies all today’s demands for studio and broadcast
telephony allowing total management of telephone lines. It is designed in a 19", 1 unit,
rackmounting container, housing 1 or 2 telephone hybrids. Units may be interconnected to
allow expansion to “n” lines whilst maintaining simplicity of use and the possibility of remote
control.
The telephone lines, appropriately filtered and isolated, allow Audioconferencing between them
and the DJ. An internal microprocessor provides a range of functions that, until now, have
been difficult to provide in the same unit. All potentiometers were eliminated in order to solve
wear problems. It is also available a socket on the rear panel to connect a headset.
Installation
AEV ITB-302 telephone hybrid has been designed and manufactured to conform to current
safety standards. The unit should only be installed by competent personnel and in compliance
with operator safety requirements and environmental specification. Great care should be taken
in making earth and ground connections to the unit and associated equipment. As for any
electronic equipment, adequate ventilation for cooling must be ensured in order to guarantee
operating temperatures within the limits defined in the Technical Specifications section. This is
particularly important in case of rack mounting or installation in confined or poorly ventilated
locations. It is advisable to leave a space between each unit and ad acent units (above and
below) even if mounted in a ventilated rack. If well connected to the rack’s ground and earth
connections, the unit will be immune to interference including RF, as long as the high
frequency units have been correctly connected. AEV ITB-302 is anyhow fitted with RF filters on

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
6
its input in order to eliminate annoying interference. Gas discharge tubes are fitted to the
telephone lines to guarantee immunity from static charges or over-voltages.
General Description
The front panel
The front panel of AEV ITB-302 is divided into 4 sections.
The first 2 sections from the left are identical and allow control over the telephone hybrids.
Four switches with associated LED indicators perform the following functions:
1 ) 2 WIRE / 4 WIRE Switches the hybrid of the section in use from 4 - wire to 2 - wire operation
2 ) MEETING Puts the line into conference mode
3 ) OFF HOOK Hangs-on the line (equivalent to picking up the handset)
4 ) 1 KHz SEND Generates a 1 KHz note at 0 dBm for local and remote ad ustment
5 ) Two level controls are situated on the input section which allow ad ustment of the receive
and send transmission levels; each one fitted with a LED level display (DOT mode), and a
trimmer to ad ust line levels.
The following controls are located in the third section:
6) BUZZER ON / AUTOLOCK SWI TCH
When turning the equipment on the buzzer will be enabled alone (incoming).
Pressing the switch successively: first it enables the Autolock and Hang-up; second it disables
the buzzer but not the Autolock and Hang-up; third it disables the Buzzer, the Autolock and
Hang-up; fourth it returns to the initial position.
7 ) PANEL/ REMOTE SWI TCH Switches between panel control or remote control.
8 ) MEETI NG L EVEL Ad usts the level during conference
The line power indicator lamp is situated in the fourth section.
The rear panel
The rear panel contains all the connectors required to connect to the outside world
1 Switch POWER Switch On/Off
2 AC POWER Line power socket
3 REMOTE 25-way Cannon connector for remote control
4 EXPANDER 1 9-way Cannon connector for expansion
5 EXPANDER 2 9-way Cannon connector for expansion
Plus two identical sections for the two lines, comprising:

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
7
6 4 WIRE RX TX 4-wire line connection
7 SEND Line input (from Mixer)
8 RECEIVE Line signal output
9 INSERT 9-way Cannon connector for insert
connection to the reception circuit and head.
10 TEL SET Line telephone connection
11 TEL LI NE Line connection for 2-wire lines
The remote control
AEV ITB-302 can be fitted with an optional
remote control, allowing control of the
hybrid and its functions. The remote control
reproduces the front panel functions of the
unit for the sections related to the two lines
and to the general one.
Two buttons are located on the upper part:
BUZZER ON/ AUTOLOCK SWI TCH
Successively pressed it enables or disables
the incoming call buzzer and Autolock with
Hang-up
functions together. Indicator leds facilitate
programming of these functions.
PANEL/ REMOTE B UTTON
Switches between panel control and remote
control.
On the lower part, two identical sections
relating to lines 1 and 2, allow control of:
2 WIRE / 4 WIRE Switches the hybrid of
the section in use from 4-wire to 2-wire
operation
MEETI NG Puts the line into
conference mode
OFF HOOK Hangs-on the line
(equivalent to picking up the handset)
1 KHz SEND Generates a 1 KHz
note at 0 dBm for local and remote
ad ustment

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
8
On telephone lines
Connections to mixer and lines
The connection of AEV ITB-302 to 2-wire telephone lines is made by inserting the telephone
cable into the corresponding socket on the ITB-302 using a standard telephone line connector.
Other telephonic equipment may be connected by inserting a standard connector in the
appropriate ITB-302 socket. This is useful for making calls and checking the line. Its onnection
is optional.
For connection to 4-wire lines it is advisable to check input and output connections.
The mixer output should be connected (balanced or unbalanced) to the hybrid’s SEND input,
whilst the feedback (RECEIVE) can be connected to the cue input of the same mixer.
WARNING: T AKE GREAT CARE I N CONNECTI NG LOOP - BACKS TO THE MI XER . F AI LURE TO DO SO CAN GENERATE
HUM , ECHOES AND “ TUBE ” EFFECTS .
Hanging-on a line
To hang-on a line, simply press the (OFF HOOK) button located on the front panel, or on the
remote control. If the autolock function has been enabled, the unit will automatically hang-on
the line after a few rings.
Adjusting levels
Once the line has been seized, ad ust the send and receive levels by in ecting the 1 KHz test
signal with the corresponding button, or with a standard signal, and calibrate the levels for a
near zero reading on the LED meters.
Conference mode
Once the line has been hang-on connection is made and maintained. The MEETING button
connects the line to the meeting circuit. In this configuration, the lines that have the relevant
MEETING button pressed, will be connected to each other enabling an audioconference.
Releasing a line
Pressing the OFF HOOK button a second time, on the front panel or on the remote control, it
releases the line. It is equivalent to putting the handset on-hook.
Remote control operation of mixer
The remote control allows the AEV ITB-302 to be installed in a conveniently located rack near
the telephone line sockets. Once the levels have been ad usted on AEV ITB-302 , the remote
control allows control of the following functions: on-hook, off-hook, conference mode etc.,
directly from the mixer or from the remote telephone location, for simple and rapid operation.
Expansions
M ORE THAN 2 LI NES
AEV ITB-302 is expandible, allowing connection of more than one unit in cascade, all remotely
controllable and able to perform audioconferencing. No modifications are necessary, except for
the addition of further units and their corresponding cables.
4 -wire lines
AEV ITB-302 features an interface for normal 2-wire lines and, as an option, for 4-wire lines.
This allows, amongst other things, connection to cellular telephones.

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
9
Tec nical Data
AUDIO LEVELS
Input level (SEND 1/2) ± 12 dBm
Input impedance >10 KΩElectronically Balanced
Connector XLR female
Output level (RECEIVE 1/2) 0 dBm
Output impedance 100 Ω Electronically Balanced (max load 600 Ω)
INSERT
Input level 0 dB
Input impedance >10 KΩ
Insert Output level 0 dB
Head Output level +10 dB
Head Output impedance 10 Ω
Head Commentator 50 Ω Unbalanced
Connector Cannon 9 pole female
HYBRID CIRCUIT
Input/output balanced and floating.
Impedance 600 Ω
RX Level - 20 ÷ 0 dBm
TX Level - 8 dBm
Hybrid null - 40 dB Full Band (on urban telephon line)
Frequency response 230 ÷ 3400 Hz
Distortion 0.8 %
4 WIRE SECTION
Impedance 600 Ω
RX Level - 12 ÷ + 12 dBm
TX Level 0 dBm
Frequency responce 50 ÷ 20000 Hz (-1 dB)
Distorsion 0.8 %
Noise ≥ 74 dB (DIN Noise)
Crosstalk ≥ 75 dB (1KHz 0dBm)
MEETING SECTION
Connector 9-contact subminiature Cannon female
Input meeting ± 12 dBm
Input meeting impedance >10 KΩ Electronically Balanced
Connector 9-contact subminiature Cannon female
Output meeting 0 dB
Output meeting impedance 100 Ω Electronically Balanced
(max load 600 Ω)
GENERAL DATA
Power supply 87 to 254 V 50/60 Hz 10 VA
Dimension 19" Rackmount 1 Unity
Weight 4.0 Kg
Attention: All cables should not be more than 3 meters length.

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
10
Connections
SEND: 1-GROUND RECEIVE: 1-GROUND
2-INPHASE 2-INPHASE
3-RETURN 3-RETURN
(option )
INSERT: 1-MIC +
2-GND
3-IN SIGNAL (Insert)
4-GND
5-OUT SIGNAL +10 dB (Head)
6-MIC -
7-GND
8-GND
9-OUT SIGNAL 0 dB (Insert)
2 WIRE: 2-N.C. 4 WIRE: 2-OUTPUT INPHASE
3-TEL. SET / TEL. LINE 3-OUTPUT RETURN
4-TEL. SET / TEL. LINE 4-INPUT INPHASE
5-N.C. 5-INPUT RETURN

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
11
Connections EXPANDERS / REMOTE
Expander 1 Expander 2
1- INPUT + 1- N.C.
2- GND 2- GND
3- INPUT - 3- N.C.
4- OUTPUT + 4- N.C.
5- GND 5- GND
6- OUTPUT - 6- N.C.
7- EXPANDER INPUT 7- EXPANDER INPUT
8- GND 8- GND
9- EXPANDER OUTPUT 9- EXPANDER OUTPUT
Remote
4 - Hook 2 (active low TTL input : internal pull-up 4K7)
16-Meeting 2 (active low TTL input : internal pull-up 4K7)
18-Hook 1 (active low TTL input : internal pull-up 4K7)
17-Meeting 1 (active low TTL input : internal pull-up 4K7)
12-Hook 2 (active low TTL output : 20 mA max)
11-Meeting 2 (active low TTL output : 20 mA max)
13-Hook 1 (active low TTL output : 20 mA max)
25-Meeting 1 (active low TTL output : 20 mA max)
6 - + 5 Volt (50 mA max)
19- + 5 Volt (50 mA max)
7 - + 5 Volt (50 mA max)
20- + 5 Volt (50 mA max)
21- GND
9- GND
22- GND
8- GND

AEV ITB302 - dual digital telephone hybrid
AEV Broadcast Srl via della Tecnica 33, 40050 Argelato (BO) ITALY
www.aev.eu - mail : [e-mail]
12