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PRO SERIES
USER MANUAL
FOR THE
PS 279
DUAL CHANNEL MASTER STATION
CONTENTS
1.0 SAFETY INSTRUCTIONS……………………………….3
2.0 GENERAL DESCRIPTION ......................................... 4
3.0 UNPACKING .............................................................. 4
4.0 MECHANICAL INSTALLATION .................................. 4
5.0 MAINS POWER .......................................................... 5
6.0 FRONT PANEL CONTROLS ...................................... 6
7.0 REAR PANEL CONTROLS ........................................ 8
8.0 INTERNAL CONTROLS ............................................. 9
9.0 CABLING .................................................................. 10
10.0 PARTY LINE, TECHNICAL CONCEP T .................... 11
11.0 WARRANTY ............................................................. 11
12.0 DESIGN CRITERIA .................................................. 11
13.0 TECHNICAL SPECIFICATIONS ............................... 12
User Manual PS 279 / Issue 1 © 2006 ASL Intercom, Utrecht, The Netherlands.
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2 User manual PS 279 / Issue 1 © 2006 ASL Intercom, Utrecht, The Netherlands
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1.0 IMPORTANT SAFETY INSTRUCTIONS !
Please always follow these instructions t o he lp ensure
against injury to yourself and da m age t o t he system.
Read all safety and operating instructions
1)
before you operate the apparatus.
Retain all safety and operating instructions for
2)
future reference.
Heed all warnings on the apparatus and in the
3)
safety and operating instructions.
Follow all installation, operating and use
4)
instructions.
Unplug the apparatus from the AC power
5)
outlet before cleaning. Use only a damp cloth
for cleaning the exterior of the apparatus.
Do not use accessories or attachments not
6)
recommended by the manufacturer, as they
may cause hazards an d vo id the warr anty.
Do not operate this apparatus in high
7)
humidity areas or expose it to water or
moisture.
Do not place the apparatus on an unstable
8)
cart, stand, tripod, bracket or table. The
apparatus may fall, causing serious personal
injury and damage to the apparatus.
Do not block or cover any openings in the
9)
apparatus. These are provided for ventilation
and protection from overheating.
Never place the apparatus near any heat
sources such as radiators, heat registers,
stoves, or other apparatus (including
amplifiers) that produce heat. Do not place the
apparatus in an enclosure such as a cabinet
without proper ventilation.
Operate the apparatus using only the type of
10)
power source indicated on the marking label.
Unplug the apparatus’ power cord by gripping
the power plug, not the cord.
Insert the plug properly. Do not defeat the
11)
safety purpose of the polarized or groundingtype plug.
A polarized AC line plug has two blades with
one wider than the other. This plug will fit into
the power outlet only one way. This is a safety
feature. If you are unable to insert the plug fully
into the outlet, try reversing the plug. If the plug
still fails to fit, contact an electrician to replace
the obsolete outlet.
A grounding type plug has two blades and a
third grounding prong. The wide blade or the
third prong are provided for your safety. If the
provided plug does not fit into your outlet,
consult an electrician to replace the obsolete
outlet.
Route power supply cords so that they are not
12)
likely to be walked on or pinched by items
placed upon or against them. Pay particular
attention to cords at plugs, convenience
receptacles, and the point where they exit from
the apparatus.
Do not overload wall outlets or extension
13)
cords, as this can result in a risk of fire or
electrical shock.
Unplug this apparatus during lightning storms
14)
or when unused for long periods of time.
Never insert objects of any kind into the
15)
apparatus through openings, as the objects
may touch dangerous voltage points or short
out parts. This could cause fire or electrical
shock.
Refer all servicing to qualified service
16)
personnel. Servicing is required w he n the
apparatus has been damaged in any way, such
as when the power-supply cord or plug is
damaged, liquid has been spilled or objects
have fallen into the apparatus, the apparatus
has been exposed to rain or moisture, does not
operate normally, or has been dropped.
User manual PS 279 / Issue 1 © 2006 ASL Intercom, Utrecht, The Netherlands 3
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2.0 GENERAL DESCRIPTION
The PS 279 is designed to be a master unit in an ASL
intercom system and can be used in portable as well as
fixed applications. It incorporates a dual channel intercom
line power supply with auxiliary input, a dual channel
headset station and uses only 1U of 19” rack space.
This makes the PS 279 very versatile and ideal for use in
applications where standard microphone cable is available
and ease of setup is of paramount importance.
Each channel has a Volume (listen level) control, a Talk
and a Call button with LED indicators and a side tone
trimmer.
The intercom line power supply is fully protected and can
drive at least 20 beltpacks operating at full power.
The power supply is completely separated from all other
functions and in case of power failure, the unit will accept
line power from an external ASL power supply.
Since the power supply provides the line impedance, one
would generally only use one PS 279 on a 2-channel
Intercom system.
Should you want to connect a PS 279 to another
Intercom system, the ‘System link’ connector at the back
of the unit has to be used to avoid impedance problems.
If the number of beltpacks/speaker stations exceed the
capacity of the PS 279 power supply, a booster power
supply (PS 285) can be used.
3.0 UNPACKING
The shipping carton contains the parts listed below
* The PS 279
* Mains power cable
* Spare fuses
* User manual
If any are missing, contact your dealer.
With the PS 279 will be a small packet of spare fuses.
Please keep them in a safe place.
There is also one spare fuse included in the mains inlet.
4.0 MECHANICAL INST ALLATION
A vertical rack space of 1U (1.75”, 44mm) is required for
the PS 279. It is not necessary to provide rear support by
extra bracing or shelving.
Adequate ventilation must be provided by allow ing
sufficient space around the sides and rear of the unit to
ensure free circulation of air. Forced cooling is not
required.
Special attention has been paid to the intelligibility of
speech. By applying low noise/high speed circuitry, a
speech presence filter and a specially designed high
power headphone amplifier, communication is very
comfortable even in environments with a high background
noise level.
The unique CALL system provides both a flashing red
LED and a very distinctive and characteristic sound signal.
Only a short push of the CALL button will make the LED
flash. The Call sound signal (buzzer) will be activated
when holding the button for two seconds. In case the
sound signal is undesirable, all buzzers can be muted with
the “All buzzers on/off” button.
Fully electronic switching increases reliability and allows
for:
- “soft” microphone ON switching, latched or momentary
- remote Mic Mute facility. All microphones of stations
connected to the PS 279 can be muted by pushing a
single front button.
An Aux input at the rear panel allows injecting external
audio signals at line level.
An Aux signal can be routed to intercom line A and/or B,
or directly to the local headset.
As an option, an XLR-6 headset connector can be fitted,
allowing the user to hear channel A + AUX program signal
on the left headset can and channel B + AUX program
signal on the right headset can. By changing the position
of internally mounted jumpers, it’s also possible to hear
channel A + B on the left can and the AUX program signal
on the right can
.
ASL has taken great care to ensure that this product
reaches you in flawless condition.
After unpacking the unit, please inspect for any physical
damage to the unit, and retain the shipping carton and
relevant packing materials for use should the unit nee d
returning.
If any damage has occurred, please notify your dealer
immediately so that a written claim can be initiated.
Please also refer to the guarantee section of this manual.
The power unit is mounted on the bottom of the unit, and
after a period of time it will feel hot to the touch on top
and bottom. This is normal, and should be no cause for
alarm
4 User manual PS 279 / Issue 1 © 2006 ASL Intercom, Utrecht, The Netherlands