Extron electronics MDA 3A User manual

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MDA 3A • User Guide
This guide describes the installation and operation of the Extron MDA 3A Mini Distribution Amplier (MDA).
Introduction
The Extron MDA 3A is a one-input, three-output audio distribution amplier. The MDA 3A distributes balanced or unbalanced
audio on captive screw connectors. The MDA 3A ships with an external desktop 12 V power supply that accepts 100 to 240 VAC,
50 Hz or 60 Hz input.
Connections, Controls, and Indicator
Figure 1 shows all of the connectors on the MDA 3A.
BAL
123
MDA 3A
POWER
12V
.3A MAX
INPUT
RL
OUTPUTS
L1R2LR LR3
UNBAL
ON
123
Distribution Amplifier
MDA 3A
5
5
5
1
1
12
2
24
4
43
3
3
Front
Rear
BAL
123
MDA 3A
POWER
12V
.3A MAX
INPUT
RL
OUTPUTS
L1R2LR LR3
UNBAL
ON
123
Distribution Amplifier
MDA 3A
5
5
5
111222444333
Front
Rear
1Power Connector 3Audio Outputs Connectors 5 Power LED
2Audio Input Connector 4Balanced/Unbalanced DIP Switches
Figure 1. MDA 3A Rear and Front Panels
Power
ATTENTION:
• Power supply voltage polarity is extremely important. Applying power with incorrect voltage polarity could damage the
power supply and the MDA. Identify the power cord negative lead by the ridges on the side of the cord.
• La polarité de la source d’alimentation est primordiale. Une alimentation avec une polarité de tension incorrecte peut
endommager la source d’alimentation ainsi que MDA. Il est essentiel d’identifier une connexion négative du cordon
d’alimentation au niveau des stries sur les parties latérales du cordon.
1Power connector (see figure1) — Plug the external 12 VDC power supply into this two-pole captive screw connector. The
power supply is included with the unit. Figure 2 shows how to wire the connector.
Power Supply
Output Cord
Orange Captive Screw
Connector
0.3 inch (7 mm) MA
X
SECTION A–A
Ridges
Smooth
AA
Tie Wrap
ATTENTION:
• If not provided with a power supply, this product is
intended to be supplied by a UL Listed power source
marked “Class 2” or “LPS”, rated output 5Vdc min.
0.5A.
• Si ce produit n’est pas fourni avec une source
d’alimentation, il doit être alimenté par une source
d’alimentation certifiée UL de classe 2 ou LPS, avec
une tension nominale 5 Vcc, 0,5 A minimum.
Figure 2. Power Connector Wiring
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MDA 3A • User Guide (Continued)
ATTENTION:
• Always use a power supply supplied by or specified by Extron for use with the MDA. Use of an unauthorized power
supply voids all regulatory compliance certification and may cause damage to the supply and the MDA.
• Utilisez toujours une source d’alimentation fournie ou spécifiée par Extron. L’utilisation d’une source d’alimentation
non autorisée annule toute certification de conformité réglementaire et peut endommager la source d’alimentation
ainsi que le produit final.
• Unless otherwise stated, the AC/DC adapters are not suitable for use in air handling spaces or in wall cavities.
The power supply is to be located within the same vicinity as the Extron AV processing equipment in an ordinary
location, Pollution Degree 2, secured to the equipment rack within the dedicated closet, podium or desk.
• Sauf mention contraire, les adaptateurs CA/CC ne conviennent pas à une utilisation dans les espaces d’aération
ou dans les cavités murales. La source d’alimentation doit être placée à proximité de l’équipement Extron dans un
emplacement ordinaire soumis à un degré de pollution de catégorie II, solidement fixé au rack d’équipement d’une
baie technique, d’un pupitre, ou d’un bureau.
• The installation must always be in accordance with applicable provisions of National Electrical Code ANSI/NFPA 70,
article 75 and the Canadian Electrical Code part 1, section 16. The power supply shall not be permanently fixed to
building structure or similar structure.
• L’installation doit toujours être conforme aux dispositions applicables du Code américain de l’électricité (National
Electrical Code) ANSI/NFPA 70, article 75, et du Code canadien de l’électricité, partie 1, section 16. La source
d’alimentation ne devra pas être fixée de façon permanente à la structure de bâtiment ou à d’autres structures
similaires.
• The length of exposed wires is important. The ideal length is 3/16 inch (5 mm) (see the NOTES on page 2 for
details).
• La longueur des câbles exposés est importante. La longueur idéale est de 5mm (3/16inches). (voir les
REMARQUES à la page12 pour plus d’informations).
• To verify the polarity before connection, plug in the power supply with no load and check the output with a
voltmeter.
• Pour vérifier la polarité avant la connexion, brancher l’alimentation hors charge et mesurer sa sortie avec un
voltmètre.
• The two power cord wires must be kept separate while the power supply is plugged in. Remove power before
wiring.
• Les deux cordons d’alimentation doivent être maintenus à l’écart tant que la source d’alimentation est branchée.
Coupez l’alimentation avant de faire les raccordements.
As an alternative, an Extron P/S 100 Universal 12 VDC Power Supply can power multiple MDAs or other Extron 12 VDC
devices using only one AC power connector.
Audio on Captive Screw Connectors
2Audio Input connector (see figure1 on the previous page) — Connect a balanced or unbalanced audio input to this 3.5
mm, five-pole captive screw connector. Connectors are included, but you must supply the audio cable. See figure3 to wire a
connector for the appropriate input type and impedance level. High impedance is generally over 800 ohms.
Unbalanced Stereo Input Balanced Stereo Input
Do not tin the wires!
Tip
Ring
Tip
Ring
Sleeves
Tip
Sleeve
Sleeve
Tip
LR
LR
inch
Figure 3. Captive Screw Input Connector Wiring
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NOTES:
• The length of exposed wires is critical. The ideal length is 3/16 inch (5 mm).
• If the stripped section of wire is longer than 3/16 inch, the exposed wires may touch, causing a short circuit.
• If the stripped section of wire is shorter than 3/16 inch, wires can be easily pulled out even if tightly fastened by the
captive screws.
• Do not tin the power supply leads before installing them in the connector. Tinned wires are not as secure in the
connector and could be pulled out.
• When making connections for the MDA from existing audio cables, see figure 4. A mono audio connector consists
of the tip and sleeve. A stereo audio connector consists of the tip, ring and sleeve. The ring, tip, and sleeve wires
are also shown on the captive screw audio connector diagrams (see figure3 and figure 4).
Tip (Left) Sleeve (Gnd)
Tip (Left)
Ring (Right)
Sleeve (Gnd)
Tip Sleeve
Unbalanced Mono Unbalanced Stereo
Tip (Signal)
Sleeve (Gnd)
Figure 4. Phono Audio Connectors
3Audio Outputs (1 through 3) connectors (see figure1 on page1) —Connect up to three balanced or unbalanced
audio devices to these 3.5 mm, five-pole captive screw connectors. Connect audio devices, such as an audio amplifier or
powered speakers. See figure 5 to properly wire an output connector.
Unbalanced Stereo Output Balanced Stereo Output
Do not tin the wires!
Tip
Ring
Tip
Ring
Sleeves
Tip
No Ground Here
No Ground Here
Tip
Sleeves
LR
LR
inch
Figure 5. Captive Screw Connector Wiring for Audio Output
ATTENTION: For unbalanced audio, connect the sleeves to the ground contact. DO NOT connect the sleeves to the
negative (-) contacts.
ATTENTION : Pour l’audio asymétrique, connectez les manchons au contact au sol. Ne PAS connecter les manchons aux
contacts négatifs (–).
NOTE: The length of exposed wires is important. The ideal length is 3/16 inch (5 mm) (see the NOTES above for details).
4Bal(anced)/Unbal(anced) DIP switches (see figure1) —For each balanced audio output, set the associated DIP switch
to the Balanced (up) position. For each unbalanced audio output, set the associated DIP switch to the Unbalanced (down)
position.
The balanced or unbalanced nature of the audio output is determined by the output connector wiring, not the audio input.
Each output can be balanced or unbalanced independently of the other two outputs.
5Power LED (see figure1) —When lit, this LED indicates power is applied to the MDA.
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68-607-50 Rev. B
05 23
For information on safety guidelines, regulatory compliances, EMI/EMF compatibility, accessibility, and related topics, see the
Extron Safety and Regulatory Compliance Guide on the Extron website.
© 2013-2023 Extron — All rights reserved. www.extron.com
All trademarks mentioned are the property of their respective owners.
Worldwide Headquarters: Extron USA West, 1025 E. Ball Road, Anaheim, CA 92805, 800.633.9876
Specifications Availability
Product specications are available on the Extron website, www.extron.com.
FCC Class A Notice
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part15 of the
FCC rules. The ClassA limits provide reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used
in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment
in a residential area is likely to cause interference. This interference must be corrected at the expense of the user.