AEQ BC-2500 User manual

A.E.Q., S.A. manufacturer of this equipment is a Registered Company
with UNE EN -ISO-9001 by AENOR ER-080/1/96 standard.
AEQ BC-2500
Broadcast Audio Mixer
USER’S MANUAL
ED. 01/03

AEQ BC-2500
Radio Broadcast Mixing Desk
3
1. GENERAL
1.1. GENERAL PRECAUTIONS
1.1.1. READ ALL INSTRUCTIONS
1.1.2. POWER SUPPLY AND EARTH CONNECTIONS
1.1.3. PROTECTION FROM EXCESSIVE SUPPLY VOLTAGE VARIATION
1.1.4. PROTECTION AGAINST WATER AND HUMIDITY
1.1.5. VENTILATION, FIRE AND INFLAMMABLE VAPOURS
1.1.6. MAINTENANCE
1.1.7. GUARANTEE
2. EQUIPMENT POWER SUPPLY
2.1. GENERAL
2.1.1. BEFORE CONNECTION TO THE MAINS SUPPLY
2.1.2. VOLTAGE SELECTION
2.1.3. SWITCHING ON THE EQUIPMENT
3. AUDIO CONNECTIONS
3.1. GENERAL
3.2. OTHER AUDIO CONNECTIONS
4. MIXER DESCRIPTION
4.1. BASIC DESIGN CONCEPTS
4.2. INITIAL CONFIGURATION
5. MODULE DESCRIPTION
5.1. BC-2511 MICRO/LINE MONOPHONIC MODULE
5.1.1.FUNCTIONAL DESCRIPTION
5.1.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.2. BC-2521 DOUBLE LINE EQUALIZED STEREO MODULE
5.2.1. FUNCTIONAL DESCRIPTION
5.2.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.3. BC-2522 DOUBLE LINE NOT EQUALIZED STEREO MODULE
5.3.1. FUNCTIONAL DESCRIPTION
5.3.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.4. BC-2533 HYBRID TELEPHONE INPUT/OUTPUT MODULE
5.4.1. FUNCTIONAL DESCRIPTION
5.4.2. EXAMPLE OF REMOTE CONNECTION OF THE HYBRID AEQ TH-02
MK-II
5.4.3. EXAMPLE OF REMOTE CONNECTION OF THE HYBRID AEQ TH-12
5.4.4. DESCRIPTION OF CONTROLS AND CONNECTORS
5.5. BC-2560-A STEREOPHONIC + SUM MONOPHONIC OUTPUT MODULE
5.5.1. FUNCTIONAL DESCRIPTION
5.5.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.6. BC-2560-C STEREOPHONIC + SUM MONOPHONIC + INPUT BYPASS
OUTPUT MODULE
5.6.1. FUNCTIONAL DESCRIPTION

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Radio Broadcast Mixing Desk
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5.6.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.7. BC-2578 MONITORING, SIGNAL AND CONTROL MODULE
5.7.1. FUNCTIONAL DESCRIPTION
5.7.1.1.CONTROL MONITORS, METERS AND PRE-LISTEN BLOCK
5.7.1.1.1. DESCRIPTION OF CONTROLS
5.7.1.2. STUDIO MONITOR BLOCK
5.7.1.2.1. DESCRIPTION OF CONTROLS
5.7.1.3. COMMAND, INTERCOM, OSCILLATOR AND TIME-SIGNAL
BLOCK
5.7.1.3.1. DESCRIPTION OF CONTROLS
5.7.1.4. STUDIO AND CONTROL MONITOR CUT AND SIGNAL
ADMINISTRATION
5.7.1.5. REMOTE FUNCTIONS
5.7.2. DESCRIPTION OF REAR CONNECTORS
5.8. BC-2523 EXTERNAL POWER SUPPLY MODULE
5.8.1. FUNCTIONAL DESCRIPTION
5.8.2. DESCRIPTION OF CONTROLS AND CONNECTORS
5.9. BC-2501 CHASSIS AND METER PANEL MODULE
5.9.1. FUNCTIONAL DESCRIPTION
6. TECHNICAL SPECIFICATIONS
6.1INPUTS
6.1.1. MICROPHONE INPUT
6.1.2. LINE INPUTS
6.1.3. BC-2511 INPUT/OUTPUT
6.1.4. BC-2533 HYBRID TELEPHONE INPUT/OUTPUT
6.1.5. BC-2578 EXTERNAL INPUTS
6.1.6. SENDS AND EQUALIZATION
6.1.7. BY-PASS INPUT
6.2. OUTPUTS
6.2.1. BC-2560 A/C MASTER AND AUXILIARY OUTPUTS
6.2.2. CONTROL AND STUDIO MONITOR OUTPUTS
6.2.3. INTERCOM
6.3. SIGNALING
6.4. POWER SUPPLY
6.5. DIMENSIONS
6.5.1. 20/24 MODULES CHASSIS DIAGRAM

AEQ BC-2500
Radio Broadcast Mixing Desk
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7. CONFIGURATION OF PROGRAMMABLE BRIDGES
7.1.BC-2511 PROGRAMMING BRIDGES
7.2.POSITION OF THE BC-2511 MODULE PROGRAMMING BRIDGES
7.3.BC-2521/22 PROGRAMMING BRIDGES
7.4. POSITION OF THE BC-2521/22 MODULE PROGRAMMING BRIDGES
7.5. BC-2560 A/C PROGRAMMING BRIDGES
7.6. POSITION OF THE BC-2560 A/C MODULE PROGRAMMING BRIDGES
7.7. BC-2533 PROGRAMMING BRIDGES
7.8. POSITION OF THE BC-2533 MODULE PROGRAMMING BRIDGES
7.9. BC-2578 PROGRAMMING BRIDGES
7.10 POSITION OF THE BC-2578 MODULE PROGRAMMING BRIDGES
APPENDIX 1: AEQ WARRANTY
BLOCK DIAGRAM

AEQ BC-2500
Radio Broadcast Mixing Desk
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1. GENERAL
1.1. General precautions
The following cautionary and security measures must be observed during all phases of
operation and maintenance of the unit. Failure to follow the instructions that are highlighted in this
manual could affect the specification and function of the equipment. AEQ. S.A. accept no
responsibility for damage or injury caused by incorrect operation of the equipment.
1.1.1. Read all the instructions.
To obtain the optimum performance and reliability from the moment of installation, and to
prevent injury, incorrect operation or damage to the equipment, it is absolutely indispensable to
thoroughly read all the instructions contained in this manual before connecting and operating the
equipment.
1.1.2. Power supply and earth connections.
To reduce the risk of electric shock, the power supply of this unit should be connected to
earth. The equipment is supplied with an earth connection socket. If it is necessary to change the
connection it should be noted that the cable to earth is marked yellow/green.
Note: The console must only be connected to the power supply module with the cable
supplied by the manufactures for this purpose. Cables of greater length may be ordered from the
manufactures if required.
1.1.3. Protection from excessive supply voltage variation.
In areas which are subject to frequent variations in the supply voltage it will be necessary
to incorporate additional external protection for the equipment, to ensure that the equipment
receives the voltage as specified in this manual.
1.1.4. Protection against water and humidity.
This equipment is not recommended for use in areas subject to ingress of rain, water etc.,
or sites with humid floors, or in places that are subject to a high degree of atmospheric humidity
that is condensing.
1.1.5. Ventilation, fire and inflammable vapours.
The equipment must not be place close to a source of heat. The use of electrical or
electronic equipment near a source of fire or in atmosphere containing inflammable vapours is
extremely dangerous and must be avoided at all cost.
All the ventilation grilles must remain unobstructed to permit sufficient ventilation and allow
the dissipation of heat to the exterior of the equipment.

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Radio Broadcast Mixing Desk
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1.1.6. Maintenance
The maintenance operations of this unit should only be carried out by qualified technical
personnel. AEQ S.A. does not accept responsibility for any damage or injury to the equipment
caused by maintenance by unauthorized persons, not for any damage or injury to other equipment
or persons caused by any unauthorized repair or maintenance operation.
Caution. A risk of severe electrical shock exists due to very high voltages that are
present in the interior of the power supply unit. Therefore proceed with absolute caution when
manipulating this unit.
The AEQ BC-2500 mixing console does not require preliminary adjustment, after
programming has been carried-out as described in this manual either by the maintenance
technician or the manufacturer, no additional operations whatsoever are necessary to obtain
optimum performance.
However it is advisable to periodically desmagnetize the input transformers of the various
modules, due to the influence this factor has on the final distortion ratio of the equipment. This
operation can be performed effectively by applying a 25 Hz signal at a level sufficient to saturate
the transformer core and then slowly diminish the signal level until annulment is achieved. It is
recommended that this operation is performed annually.
Note: In the event that the maintenance technician requires to change the location of the unit or
incorporate new modules in the equipment, the following procedure must be adopted:
1) Turn off the equipment using the on/off switch located at the rear of the power supply
module BC-2523.
2) Proceed to the removal of the module(s) for interchange by removing the chassis fixing
screws located at both end of the panel.
3) Disconnect the internal bus by loosening the ribbon cable connector located in the
lower middle part of the printed circuit board and the rear mounted connectors if fitted.
Module replacement is effected by the direct reversal of the operations described above.
1.1.7. Guarantee.
Guarantee period: The terms and conditions are as stated in the APPENDIX 1 of this
manual.

AEQ BC-2500
Radio Broadcast Mixing Desk
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2. EQUIPMENT POWER SUPPLY
2.1. General
A description of the module to power supply connection is detailed in Section 5.7 and 5.8.
2.1.1. Before connection to the mains supply
Caution: Before the equipment is connected to the power supply, the voltage selector
must be checked an if necessary set for the supply voltage as in Section 2.1.2. and the DC power
supply cable connected between module BC-2578 and the power supply BC-2523. The procedures
detailed in this section must be followed carefully before connecting and operating the equipment.
2.1.2. Voltage selection.
The AEQ BC-2500 mixer is designed to operate with a 110/220 V AC power supply. Set
the VOLTAGE SELECTOR (see Section 5.8 of this manual) to appropriate network supply voltage.
If the 110 V AC supply voltage is selected, the fusible link fitted as standard to the
equipment must be replaced by the alternative that can be found in the plastic bag containing this
manual, and following these instructions. Remove the fuseholder located in the rear of the power
supply module BC-2523 (see section 5.8 of this manual), and replace the existing fuse with the
alternative as mentioned previously.
Remember: 220 V AC Power supply = 1.6 A Fuse Type T
110 V AC Power Supply = 2.5 A Fuse Type T
Note: The equipment can be supplied with 220 AC or 110 AC volts supply.
Note: The power supply cable is supplied with a European Standard mains
interconnecting plug. In certain countries it could be necessary to exchange this plug to adapt to
the prevailing local standards. If this is the case, the substitution of the plug should be carried-out
before proceeding.
Note: Signallig circuit has its own fuse. This one is a 1 Amp fuse.
2.1.3. Switching on the equipment.
Once the checks and/or modifications indicated in the Section 2.1.2. have been
accomplished the equipment is prepared for connection to the electric supply network. Prior to
connection ensure that power supply switch POWER is in the off position.
Activate the power supply switch POWER. If all the previous instruction have been
correctly followed, the LED’s labelled as +ANALOG and -ANALOG of the control module BC-
2578 will illuminate, indicating that the equipment is receiving power supply.
Note: For the location of the power switch an LED’s indicators mentioned above, refer to sections
5.7. and 5.8. of this manual.

AEQ BC-2500
Radio Broadcast Mixing Desk
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3. AUDIO CONNECTIONS
3. 1. General
The audio connections of the AEQ BC-2500 mixer comply with the AES 14-1992 (ANSIS
4.48-1992) recommendations. This recommendation is based on IEC 268-12 of 1987. Equipment
for sound systems part 12, application of connectors for radio broadcast and similar uses.
The audio connection cables should be checked for compatibility with the standards
indicated. If this is not the case they must be exchanged or modified since problems could be
encountered with the phase of the audio signal.
male pin connector
female socket
connector
equipment output
equipment input
1 2
3
Application &
Power Supply
Balanced
Mono Channel
Unbalanced
Mono Channel
Balanced Mono
Channel.
Phantom Power
Balanced Mono
Channel
Power A-B
1
Screen
Screen & Return
Screen & Negative
Power
Screen
2 3
Positive Polarity
Positive Polarity
Polarity &Positive Power
Polarity &Positive Power
Return
NOTE 1*
Return & Positive Power
Return & Negative Power
NOTE 1*
If a balanced
microphone is
connected to an
unbalanced
amplifier
input,the input
contact 3 is
connected to
contact 1.
PIN NUMBER
3. 2. Other audio connections.
The BC-2578 module multipin connector wiring layout is described in section 5.7.2. of this
manual.
The BC-2511 module 1/4” jack connectors are wiring according to the following diagram:
RETURN
SEND
COMMON

AEQ BC-2500
Radio Broadcast Mixing Desk
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4. MIXER DESCRIPTION
4.1. Basic design concepts.
The AEQ BC-2500 Audio Mixer has been designed for use in radio broadcast studios
together with mobile units, television and sound installations where the quality and reliability of the
equipment are fundamental factors.
The criteria base for development and fabrication of the audio mixer were based on our extensive
experience in the field of radio broadcasting and direct contact with the professionals in the sector.
This has allowed us to capture the necessity of an audio mixer for radio and television in line with
current technology and with the highest performance.
The design and configuration assures rapid assimilation of the mixer functions by the user. The
logical distribution of the controls and the automatic monitor and signal cut features simplify the
operator tasks.
The modular concept allows the extraction of any module for repair or replacement in a
few moments. The high quality of the components used in manufacture guarantees the prolonged
service life of the equipment.
The AEQ BC 2500 audio mixer is user configurable according to the specific
requirements. Beginning with the standard ex-works configuration, it is easily upgraded by
incorporating new input modules or it can be redistributed according to operator preferences.
The following details some of the characteristics that make the AEQ BC 2500 mixer an
excellent piece of equipment for utilization in radio and television broadcasters.
-Programmable micro input channels for autocontrol or announcer control by means of
internal programmable bridges.
-Fader control of VCA signal.
-Indirect control of the principal outputs.
-Electronically balanced buses.
-Transformed balanced inputs and outputs.
-External inputs 1 and 2 Electronically balanced.
-Input channel RF filters.
-Lock-in metal XLR connectors.
-Output to auxiliary programmable pre or post fader by internal bridges.
-Remote Mute and PFL from the announcer.
-Input module saturation and “clipping” indicators.
-Stereo pre-listening.
-Input/output module compatible with an external hybrid telephone, with independent
control and PFL for both input and output.
-Output modules with simultaneous stereophonic/monophonic function.
-Output modules with simultaneous stereophonic/monophonic function with exterior
stereo input which is “bypassable” to the stereo output.
-Independent headphone controls for the controller, the primary and secondary
announcers.
-4 way intercom for communication of instructions to or from the exterior, co-ordination
of mobile units, microphone lines, etc...
-Automatic signal activation ON AIR through input modules, programmable by
internal bridges.
-24 volts power supply for signaling.

AEQ BC-2500
Radio Broadcast Mixing Desk
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4.2. Initial Configuration
The AEQ BC-2500 audio mixer is supplied with two basic configurations:
BC-2500 FM-AUTOCONTROL
1BC-2501FM Chassis with capacity for 24/20 modules, with audio meters and PFL
monitor loudspeakers.
1BC-2578 Control, monitor and “intercom” module for controller and announcer.
(occupies three module space)
2BC-2511 Micro/line mono input module.
5BC-2522 Double switchable stereo input module.
1BC-2533 External hybrid telephone input/output and control module.
2 BC-2560-AStereo plus added mono output module.
7 BC-2502 Blank module.
1BC-2523 External power supply module.
(This module does not occupy chassis space)
BC-2500 FM ANNOUNCER-CONTROL
1BC-2501FM Chassis with capacity for 24/20 modules, with audio meters and PFL
monitor loudspeakers.
1BC-2578 Control, monitor and “intercom” module for controller and announcer.
2BC-2511 Micro/line mono input module.
6BC-2522 Double switchable stereo input module.
2BC-2533 External hybrid telephone input/output and control module.
2 BC-2560-AStereo plus added mono output module.
3 BC-2502 Blank module. (This module does not occupy chassis space)
1BC-2523 External power supply module.
Other configurations are available on demand, only limited by the spatial capacity of the
chassis. The minimum functional requirement is the inclusion of one BC-2501 or BC-2501FM
module, one BC-2578 module, one input and one output module, an external power supply and
blanking plates to complete the chassis.

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Radio Broadcast Mixing Desk
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5. MODULE DESCRIPTION
5.1. BC-2511 MICRO/LINE MONO INPUT MODULE.
5.1.1. Functional description.
The micro/line mono input module BC-2511 permits the connection of two independent
inputs; one microphone level (21) and the other line level (22), selection being carried-out by
means of the switch (1) MICRO/LINE.
Push-bottom (3) HFF activates a radiofrequency filter. (100 Hz)
Once the input type is selected, the level is adjusted by the potentiometer (2) GAIN, an external
signal can then be introduced through the connector (20) INSERT, subsequently the equalization
can be adjusted by the potentiometers (4, 5, 6 and 7) TREBLE, MID/FREQ, MID/GAIN and
BASS, corresponding to the treble level, mid frequencies gain and bass level respectively,
whenever the equalization circuit is activated by the switch (8) EQ ON.
With the aim of avoiding saturation an LED indicator (9) CLIP illuminates on reaching
maximum signal level. If required this signal can be monitored by activating Push-button (16) PFL
ON, to send it to the pre-listen bus. This status is confirmed by the illumination of led indicator
(17).
Potentiometer (12) BALANCE regulates the left/right channel output signal balance.
The output signal can be directed to the following outputs whenever the operative channel
selector (18) CHANNEL ON is activated:
Master 1, adjusts the send level with fader (19) and pushing the switch (13) MASTER 1
Master 2, adjusts the send level with fader (19) and pushing the switch (14) MASTER 2
Telephone buses 1 and 2, adjust the send level with fader (19) and pushing the switch (15)
PHONE.
This signal can also be sent to the following auxiliary outputs:
Auxiliary 1, the send level is adjusted with potentiometer (10) AUX 1 if working with the Auxiliary 1
send programmed pre-fader or the send level is adjusted with fader (19) once the send level to
Auxiliary bus 1 is set with potentiometer (10) AUX 1 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (18) CHANNEL ON is
activated.
Auxiliary 2, the send level is adjusted with potentiometer (11) AUX 2 if working with the Auxiliary 2
send programmed pre-fader or the send level is adjusted with fader (19) once the send level to
Auxiliary bus 1 is set with potentiometer (11) AUX 2 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (18) CHANNEL ON is
activated.
The position of the programming bridges and their functions are described in Section 7 of
this manual.

AEQ BC-2500
Radio Broadcast Mixing Desk
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5.1.2. Description of Controls and Connectors.
1
2
3
4
5
6
7
8
10
9
11
12
13
14
15
16
17
18
19
1.-Input switch MICRO/LINE
2.-Gain adjusting potentiometer GAIN
3.-Radiofrequency switch HFF
4.-Treble frequency level adjusting potentiometer TREBLE
5.-Middle frequency parametric equalizer potentiometer
MID/FREQ
6.-Middle frequency level adjusting potentiometer MID/GAIN
7.-Bass frequency level adjusting potentiometer BASS
8.-Equalizer activation switch EQ.ON
9.-Saturation level led indicator CLIP
10.-Send to auxiliary 1 bus potentiometer AUX. 1
11.-Send to auxiliary 2 bus potentiometer AUX. 2
12.-Balance level adjusting potentiometer BALANCE
13.-Send to master 1 output bus switch MASTER 1
14.-Send to master 2 output bus switch MASTER 2
15.-Send to telephone bus switch PHONE
16.-Send to pre-listen bus push-button PFL ON
17.-Pre-listen active led indicator PFL ON
18.-Channel activation switch CHANNEL ON
19.-Output level slide potentiometer FADER
20.-Input/output connector socket INSERT
21.-Microphone input connector MICRO
22.-Line input connector LINE
20
21
22
REAR
FRONT

AEQ BC-2500
Radio Broadcast Mixing Desk
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5.2. BC-2521 DOUBLE LINE EQUALIZED STEREO INPUT MODULE.
5.2.1. Functional description
The Double Line Equalized Stereo Input Module BC-2521 permits the connection of two
stereo inputs A and B. These lines are connected to (23) INPUT A (L) and (24) INPUT A (R) for
the left and right Line A channels and (26) INPUT B (L) and (27) INPUT B (R) for the left and rigth
Line B channels, selection is by switch (1) INPUT A/B. If the selector is at rest input A is active,
when the selector is depressed input B is selected.
The gain of the selected input is adjusted with potentiometer (3) GAIN.
It is possible to convert this signal to mono by activating switch (2) ST/MONO
Switch (4) HFF activates a radiofrequency filter. (100 Hz)
Subsequently the equalization can be adjusted by the potentiometers (5, 6, 7 and 8) TREBLE,
MID/FREQ, MID/GAIN & BASS, corresponding to the treble level, mid frequencies, mid
frequencies gain and bass level, respectively, whenever the equalization circuit is activated by the
switch (9) EQ ON.
With the aim of avoiding saturation a led indicator (10) CLIP illuminates on reaching
maximum signal level. If required this signal can be monitored by activating Push-button (18) PFL
ON, to send it to the pre-listen bus. This status is confirmed by the illumination of led indicator
(19).
Potentiometer (12) BALANCE regulates the left/right channel output signal balance. This
function is activated when switch (14) BALANCE ON is activated.
The output signal can be directed to the following outputs whenever the operative switch
(20) CHANNEL ON is activated:
Master 1, adjusts the send level with fader (21) and pushing the switch (15) MASTER 1
Master 2, adjusts the send level with fader (21) and pushing the switch (16) MASTER 2
Telephone buses 1 and 2, adjust the send level with fader (21) and pushing the switch (17)
PHONE.
This signal can also be sent to the following auxiliary outputs:
Auxiliary 1, the send level is adjusted with potentiometer (11) AUX 1 if working with the Auxiliary 1
send programmed pre-fader or the send level is adjusted with fader (21) once the send level to
Auxiliary bus 1 is set with potentiometer (11) AUX 1 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (20) CHANNEL ON is
activated.
Auxiliary 2, the send level is adjusted with potentiometer (12) AUX 2 if working with the
Auxiliary 2 send programmed pre-fader or the send level is adjusted with fader (21) once the send
level to Auxiliary bus 1 is set with potentiometer (12) AUX 2 when working with the send to
auxiliary 1 programmed as post-fader and whenever the channel operative switch (20) CHANNEL
ON is activated.
The position of the programming bridges and their functions are described in Section 7 of
this manual.

AEQ BC-2500
Radio Broadcast Mixing Desk
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5.2.2. Description of Controls and Connectors.
1.-A/B Input selector switch INPUT A/B
2.-Mono/stereo selector switch ST/MONO
3.-Gain adjusting potentiometer GAIN
4.-Radiofrequency switch HFF
5.-Treble frequency level adjusting potentiometer TREBLE
6.-Middle frequency parametric equalizer potentiometer
MID/FREQ
7.-Middle frequency level adjusting potentiometer MID/GAIN
8.-Bass frequency level adjusting potentiometer BASS
9.-Equalizer activation switch EQ.ON
10.-Saturation level led indicator CLIP
11.-Send to auxiliary 1 bus potentiometer AUX. 1
12.-Send to auxiliary 2 bus potentiometer AUX. 2
13.-Balance level adjusting potentiometer BALANCE
14.-Balance activation switch BALANCE ON
15.-Send to master 1 output bus switch MASTER 1
16.-Send to master 2 output bus switch MASTER 2
17.-Send to telephone bus switch PHONE
18.-Send to pre-listen bus push-button PFL ON
19.-Pre-listen active led indicator PFL ON
20.-Channel activation switch CHANNEL ON
21.-Output level slide potentiometer FADER
22.-Line A remote connectors REMOTE A
23.-Line A left input connector INPUT A(L)
24.-Line A rigth input connector INPUT A (R)
25.-Line B remote connectors REMOTE B
26.-Line B left input connector INPUT B (L)
27.-Line B rigth input connector INPUT B (R)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
FRONT
REAR

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Radio Broadcast Mixing Desk
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5.3. BC-2522 DOUBLE LINE STEREO INPUT MODULE.
5.3.1. Functional description
The Double Line Stereo Input Module BC-2522 permits the connection of two stereo inputs
A and B. These lines are connected to (18) INPUT A (L) and (19) INPUT A (R) for the left and right
Line A channels and (21) INPUT B (L) and (22) INPUT B (R) for the left and rigth Line B channels,
selection is by switch (1) INPUT A/B. If the selector is at rest input A is active, when the selector
is depressed input B is selected.
The gain of the selected input is adjusted with potentiometer (3) GAIN.
It is possible to convert this signal to mono by activating switch (2) ST/MONO
Switch (4) HFF activates a radiofrequency filter. (100 Hz).
With the aim of avoiding saturation a led indicator (5) CLIP illuminates on reaching
maximum signal level. If required this signal can be monitored by activating Push-button (13) PFL
ON, to send it to the pre-listen bus. This status is confirmed by the illumination of led indicator
(14).
Potentiometer (8) BALANCE regulates the left/right channel output signal balance. This function is
activated when switch (9) BALANCE ON is activated.
The output signal can be directed to the following outputs whenever the operative channel
selector (15) CHANNEL ON is activated:
Master 1, adjusts the send level with fader (16) and pushing the switch (10) MASTER 1
Master 2, adjusts the send level with fader (16) and pushing the switch (11) MASTER 2
Telephone buses 1 and 2, adjust the send level with fader (16) and pushing the switch (12)
PHONE.
This signal can also be sent to the following auxiliary outputs:
Auxiliary 1, the send level is adjusted with potentiometer (6) AUX 1 if working with the Auxiliary 1
send programmed pre-fader or the send level is adjusted with fader (16) once the send level to
Auxiliary bus 1 is set with potentiometer (6) AUX 1 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative selector (15) CHANNEL ON is
activated.
Auxiliary 2, the send level is adjusted with potentiometer (7) AUX 2 if working with the Auxiliary 2
send programmed pre-fader or the send level is adjusted with fader (16) once the send level to
Auxiliary bus 1 is set with potentiometer (7) AUX 2 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (15) CHANNEL ON is
activated.
The position of the programming bridges and their functions are described in Section 7 of
this manual.

AEQ BC-2500
Radio Broadcast Mixing Desk
17
5.3.2. Description of Controls and Connectors.
1.-A/B Input selector switch INPUT A/B
2.-Mono/stereo selector switch ST/MONO
3.-Gain adjusting potentiometer GAIN
4.-Radiofrequency switch HFF
5.-Saturation level led indicator CLIP
6.-Send to auxiliary 1 bus potentiometer AUX. 1
7.-Send to auxiliary 2 bus potentiometer AUX. 2
8.-Balance level adjusting potentiometer BALANCE
9.-Balance activation switch BALANCE ON
10.-Send to master 1 output bus switch MASTER 1
11.-Send to master 2 output bus switch MASTER 2
12.-Send to telephone bus switch PHONE
13.-Send to pre-listen bus push-button PFL ON
14.-Pre-listen active led indicator PFL ON
15.-Channel activation switch CHANNEL ON
16.-Output level slide potentiometer FADER
17.-Line A remote connectors REMOTE A
18.-Line A left input connector INPUT A (L)
19.-Line A rigth input connector INPUT A (R)
20.-Line B remote connectors REMOTE B
21.-Line B left input connector INPUT B (L)
22.-Line B rigth input connector INPUT B (R)
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AEQ BC-2500
Radio Broadcast Mixing Desk
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5.4. BC-2533 HYBRID TELEPHONE INPUT/OUTPUT MODULE.
5.4.1. Functional description
The Hybrid Telephone Input/Output Module BC-2533 permits the adaptation of an external
analogue or digital hybrid telephone to the other modules that make up the system.
An audio input (20) INPUT FROM LINE is available for the signal from the external hybrid
telephone at line level. This input can be monitored by activating the push-button PFL INPUT (16)
the status is shown by the illumination of the PFL led. PFL INPUT (14).
The output signal can be directed to the following outputs whenever the operative channel
selector (17) CHANNEL ON is activated:
Master 1, adjusts the send level with fader (18) and pushing the switch (11) MASTER 1
Master 2, adjusts the send level with fader (18) and pushing the switch (12) MASTER 2
Auxiliary 1, the send level is adjusted with potentiometer (9) AUX 1 if working with the Auxiliary 1
send programmed pre-fader or the send level is adjusted with fader (18) once the send level to
Auxiliary bus 1 is set with potentiometer (9) AUX 1 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (17) CHANNEL ON is
activated.
Auxiliary 2, the send level is adjusted with potentiometer (10) AUX 2 if working with the Auxiliary 2
send programmed pre-fader or the send level is adjusted with fader (18) once the send level to
Auxiliary bus 1 is set with potentiometer (10) AUX 2 when working with the send to auxiliary 1
programmed as post-fader and whenever the channel operative switch (17) CHANNEL ON is
activated.
Press button (5) MULTIPLEX. When this function is activated in two BC-2533 modules (if both are
available in the console) the telephone lines associated with each one of them are interlinked.
The output signal from this module is the sum of all the sends in the telephone buses 1
and 2 PHONE, from the type BC-2511, BC-2521 & BC-2522 input modules. The monitoring of the
same is through the pre-listen bus activated by the push-button (15) PFL OUTPUT, the status is
reflected by the illumination of the led (13) PFL OUTPUT. The signal outputs via connector (21)
OUTPUT TO LINE and is sent to the external hybrid telephone; the level is adjusted by the
potentiometer (1) OUTPUT LEVEL.
This module also disposes of a remote control interface to allow control of an external hybrid
telephone of one or two lines and it has the controls and indicators necessary for this function,
namely:
Luminous led indicators (3) and (7) RING to signal incoming calls on line 1 and/or line 2.
Input “to air” switches (4) AIR 1and (8) AIR 2 in order to effect the connection of the
hybrid to telephone lines one and two (line busy / line available).
Call waiting switches (2) WAIT 1and (6) WAIT 2 to pass to the communications on line
one and/or two of the hybrid phone on hold. (This function is not available unless the Hybrid is
an AEQ TH-02 and the remote connectors for these functions are properly wired for both
the Hybrid and the Module) When this function is activated the callers are able listen to the
module output, but are not able to intervene, since the input remains blocked.

AEQ BC-2500
Radio Broadcast Mixing Desk
19
These are the diagrams of the internal configuration of the remote signals:
Note: The BC-2533
module can be programmed for connection to telephone bus 1 or 2. This
operation is performed
during manufacturate. To alter this specification our Technical Service
department should be consulted. It should be noted that two BC-
2533 modules must never be
connected to the same telephone bus.

AEQ BC-2500
Radio Broadcast Mixing Desk
20
5.4.2. Example of remote connection of the Hybrid AEQ TH-02 MKII
BC-2533 TH-02 MKII
Module. Hybrid pin connector.
5.4.3. Example of remote connection of the Hybrid AEQ TH-12
Module BC-2533 TH-12
Module. Hybrid pin connector.
Note: The situation of P.D.P. (program bridges) varies according to the AEQ external hybrid model
selected. Consult Section 7 for further explanation.
If you own an EAGLE ISDN Audiocodec, you can use it as an hybrid. Read EAGLE Users
Manual in order to make the connection.
REMOTE
INPUT FROM LINE
OUTPUT TO LINE
REMOTE
OUTPUT
INPUT
REMOTE RING 1
REMOTE AIR 1
INPUT FROM LINE
OUTPUT TO LINE
RING
AIR
OUTPUT
INPUT

AEQ BC-2500
Radio Broadcast Mixing Desk
21
5.4.4. Description of Controls and Connectors.
1.-Output level adjusting potentiometer OUTPUT LEVEL
2.-Wait 1 switch WAIT 1
3.-Call on line 1 luminous indicator RING
4.-Line 1 “TO AIR” switch AIR 1 (line busy)
5.-Interconnection with a second BC-2533 switch MULTIPLEX
6.-Wait 2 switch WAIT 2
7.-Call on line 2 luminous indicator RING
8.-Line 2“TO AIR” switch AIR 2
9.-Send to auxiliary 1 bus potentiometer AUX.1
10.-Send to auxiliary 2 bus potentiometer AUX.2
11.-Send to master 1 output bus switch MASTER 1
12.-Send to master 2 output bus switch MASTER 2
13.-Output pre-listen activated led indicator PFL OUT
14.-Input pre-listen activated led indicator PFL IN
15.-Output pre-listen activation push-button PFL OUT
16.-Input pre-listen activation push-button PFL IN
17.-Channel activation switch CHANNEL ON
18.-Output level slide potentiometer FADER
19.-Hybrid remote control connector REMOTE. DB15-Male pin
20.-Line output connector OUTPUT TO LINE
21.-Line input connector INPUT FROM LINE
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