ASL INTERCOM PS 19 User manual

PS 19
SINGLE CHANNEL BELTPACK
USER MANUAL
Issue 2010 © ASL Intercom BV
DESIGNED AND MANUFACTURED BY:
ASL INTERCOM BV
ZONNEBAAN 42
3542 EG UTRECHT
THE NETHERLANDS
PHONE: [phone]
FAX: [phone]
E-MAIL: in[email protected]
WEB: www.asl-inter.com

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User Manual PS 19 / Issue 2010 © ASL Intercom BV
CONTENT OF THIS USER MANUAL
1.0 GENERAL DESCRIPTION..................................................................................2
2.0 UNPACKING..........................................................................................................2
3.0 INSTALLATION.....................................................................................................2
4.0 WARRANTY...........................................................................................................2
5.0 FRONT PANEL CONTROLS..............................................................................3
6.0 REAR PANEL CONNECTORS ..........................................................................4
7.0 INTERNAL CONTROLS......................................................................................4
8.0 TECHNICAL SPECIFICATIONS........................................................................4
9.0 PART LINE, TECHNICAL CONCEPT...............................................................5
10.0 CABLING................................................................................................................5
11.0 PS 19 BLOCK DIAGRAM....................................................................................6
12.0 SYSTEM CONFIGURATION...............................................................................6
13.0 EARTHING CONCEPT ........................................................................................7

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User Manual PS 19 / Issue 2010 © ASL Intercom BV
1.0 GENERAL DESCRIPTION
The PS 19 is a portable single channel intercom
station. It is housed in a strong ABS case
provided with a steel belt clip.
On the front panel are a Volume (listen level)
control, a TALK and a CALL push button with
LED indicators, a side tone trimmer and a buzzer
volume trimmer. On the rear panel are XLR-3
connectors for the intercom connection cable (the
‘party line’) and an XLR-4 connector for the
headset.
Special attention has been paid to the
intelligibility of speech. By applying low noise /
high speed op-amps, a speech presence filter
and propriety high power bridged headphone
amplifiers, communication is very comfortable
even in environments with a high level of
background noise.
The unique ASL call system provides both a
flashing red LED and a very distinctive sound
signal. A momentary push of the Call button
makes the red LED flash whilst holding the button
for 2 seconds activates the Call sound signal.
The volume of this sound signal (the buzzer) can
be adjusted at the front panel.
Fully electronic switching increases reliability and
allows for:
‘soft’ microphone On switching, latched
and momentary
Remote Mic Mute facility
2.0 UNPACKING
The shipping carton contains the PS 19 and this
user manual. If any are missing, contact your
dealer.
ASL has taken great care to ensure this product
reaches you in flawless condition.
After unpacking the unit please inspect for any
physical damage and retain the shipping carton
and relevant packing materials for use should the
unit need returning.
If any damage has occurred, please notify your
dealer immediately so that a written claim can be
initiated. Please also refer to the warranty section
of this manual.
3.0 INSTALLATION
This PS 19 will form a part of an existing or new
intercom system. Connection to it is
straightforward. There are no separate power
connections or batteries to install as the
necessary DC voltages are derived from the
intercom master station or power supply, via the
intercom connection cable.
To connect the PS 19 to the intercom system use
professional flexible microphone cable with 2
wires and 1 shield only. Connect this cable to the
LINE connector on the rear panel.
The PS 19 is fully protected against mis-wiring
(reverse power) or short circuit in the
interconnecting cables.
4.0 WARRANTY
This unit is warranted by ASL to the original end-
user purchaser against defects in workmanship
and materials in its manufacture for a period of
12 months from date of shipment to the end-user.
Faults arising from misuse, unauthorized
modifications or accidents are not covered by this
warranty. If the unit is faulty it should be sent, in
its original packing, to the supplier or your local
ASL dealer, shipping costs prepaid. A note must
be included stating the fault(s) found and a copy
of the original suppliers invoice.

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User Manual PS 19 / Issue 2010 © ASL Intercom BV
5.0 FRONT PANEL CONTROLS
1 VOLUME control knob
With this knob the listen level for the headset is
adjusted
2 TALK button
By pushing this button the signal of the headset
microphone is sent to the intercom party line.
When the TALK button is switched On, its large
green LED is lit.
Momentary switching:
When the TALK button is pushed and held, the
microphone signal is sent to the intercom channel
until the button is released.
Latched switching:
When the TALK button is pushed shortly it is
electronically latched and the microphone signal
is sent to the intercom channel. When pushed
again the TALK button switches Off.
Mic Mute when latched On:
After a so-called Mic Mute signal has been
received from a Pro Series master station or
power supply, the connection between
microphone and intercom channel is interrupted.
By pushing the TALK button, the connection is
restored and one can talk to the intercom channel
again.
3 CALL button
By pushing this button the Call function is
activated. With a momentary push a Call signal
is sent to all stations connected to the intercom
party line. The Call LED’s of this beltpack and of
all stations on the party line start flashing.
By pushing the Call button for 2 seconds the Call
Buzzers are activated, provided the buzzers are
not muted by a Buzzer Mute signal received from
a Pro Series master station or power supply.
After the CALL button is released the LED’s
continue to flash for a further 2 seconds.
4 SIDE TONE trimmer
This trimmer adjusts the level of one’s own voice
in one own headset.
Adjustment procedure:
Set trimmer in start position: turn fully
clockwise
Switch Off the microphones of all
(speaker) stations connected to the party
line
Push the TALK button
Turn up the listen volume
Speak into the headset microphone
Adjust the listen level by turning the side
tone trimmer
The operating area of the trimmer is between
fully clockwise and minimum level. Adjusting the
side tone does not affect the level of your voice
as heard by the other stations on the party line.
5 BUZZER VOLUME trimmer
This trimmer adjusts the volume of the internal
buzzer (located behind the front panel).
The buzzer is activated when the CALL button on
this beltpack (or on any other intercom station
connected to the party line) is pushed longer than
2 seconds, provided the buzzers are not muted
by a Buzzer Mute signal received from a Pro
Series master station or power supply.

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User Manual PS 19 / Issue 2010 © ASL Intercom BV
6.0 REAR PANEL CONNECTORS
6 LINE connectors
These XLR-3 connectors are for connecting the
intercom party line. The female connector is for
input and the male connector for extending the
intercom party line to other stations (daisy chain)
Pin assignments:
Pin 1: 0V / ground shield
Pin 2: +30V DC power wire
Pin 3: audio wire
7 HEADSET connector
This XLR-4 connector is for connecting a headset
to the beltpack. The impedance of the headset
can must be minimum 200 ohms; in case the
headset has 2 cans in parallel, the impedance of
each can must be minimum 400 ohms.
Pin assignments:
Pin 1: shield mic. (GND)
Pin 2: mic. +
Pin 3: phones +
Pin 4: phones –
7.0 INTERNAL CONTROLS
MIC GAIN trimmer
By this trimmer the mic gain is adjusted. One has
to open the PS 19 by removing the 4 screws at
the underside. The trimmer is situated on the
lower PCB board. To increase the gain, turn
clockwise. To decrease the gain, turn counter
clockwise.
8.0 TECHNICAL SPECIFICATIONS
System Specifications
Dynamic range: 80 dB (1 kHz, THD , 1%)
Call signal: 2.8 mA
Call signal threshold (receive): +2.4V DC
Supply voltage: + 30V DC (12 –32V DC)
Power interrupt time (mic mute): 0.1 sec
Line Impedance: 350 Ω (1 kHz) / 2.2 kΩ (DC)
Audio level: nom. -18 dBu, max. +4 dBu
Mic pre-amp
Headset mic. impedance: 200 Ω
Gain: 40 –60 dB (adjustable internally)
Presence filter: +6 dB at 5 kHz
Frequency response: 200Hz - 15 kHz (-3 dB)
Power to electret mic: +9V DC
Headphone Driver Amps
Max output level: 14 Vrms @ 200 Ω
Max output power: 2x 0.28 Wrms @ 400 Ω
Side Tone
Rejection: 0 –30 dB adjustable
Buzzer
Max. SPL: 85 dBA
PS 19 Power Consumption
Current (at 30V DC):
30 mA quiescent
45 mA signalling
170 mA at max. output + signaling
PS 19 Dimensions & Weight
Width: 90 mm / Height: 38 mm
Depth: 124 mm / Weight: 295 grams
0 dB is defined as 775 mV into open circuit
ASL reserves the right to alter specifications
without prior notice

9.0 PART LINE, TECHNICAL CONCEPT
User stations and power supplies in an ASL intercom
system are connected via one or several 'party lines'.
A party line offers two way (‘full duplex’)
communication and consists of standard microphone
(multi-pair) cable. One wire is used as an audio line,
one as a power line and the screen of the cable
functions as earth/return.
Current drive is used for signal transfer.
Each station utilizes a current amplifier to amplify the
microphone signal. That signal is put on the common
audio line. Due to the constant line impedance, a
signal voltage is developed which can be further
amplified and sent to the headphones or loudspeakers.
This principle has three advantages:
othe use of a single audio line allows several
stations to talk and listen simultaneously
odue to the high bridging impedance offered by
each station, the number of stations on the
party line has no influence on the level of the
communications audio signal
opower and audio to the intercom stations use
the same cable
Also the Call signal is sent as a current, on the
audio wire. It develops a DC potential over the line
impedance which is sensed by each intercom
station and interpreted as a Call signal.
10.0 CABLING
The intercom lines (the ‘party lines’) in an ASL analog intercom system are of the shielded two-conductor microphone
cable type. The intercom line connectors are of the XLR-3 type. Audio and Call signals are on pin 3, DC power is on
pin 2 and pin 1 is connected to the shield of the cable which functions as the common return for audio and power.
The audio signal is transferred in an unbalanced way (see ‘Party Line, Technical Concept’).
To avoid earth loops (hum), the possible effect of electromagnetic fields and to minimize power loss, certain rules
have to be obeyed when installing the cabling of an intercom system :
Use high quality cable
Use high quality microphone cable (shielded two
conductor cable, minimum 2x 0.30 mm2). In case
multi-pair microphone cable is used, there should be
an overall shield and each pair should consist of two
conductors (minimum 2x 0.15 mm2) with separate
shield
Use flexible cable
Use flexible single and multi-pair microphone cable
instead of cable with solid cores, especially when the
cable is subjected to bending during operation or
installation.
Cable screens to XLR pin 1
The screen of each separate microphone cable and/or
the screen of each single pair in a multi-pair cable,
should be connected to pin 1 of each XLR-3
connector. Do not connect these screens to the metal
housing of ASL units or XLR-3 wall boxes.
See section ‘Earthing Concept’.
Connect metal cable trunks, wall boxes and overall
multi-pair cable screens to clean earth
Metal cable trunks, metal wall boxes and overall multi-
pair cable screens should be interconnected and, at
the 'central earth point' in the intercom network only,
be connected to a clean earth or a safety earth.
See section ‘Earthing Concept’.
Keep metal connection boxes and cable trunks or
pipes isolated from other metal parts
Metal trunks or pipes for intercom cables and metal
connection boxes should be mounted in such a way
that they are isolated from any other metal housing or
construction part.
Keep cables parallel as much as possible
When two (multi channel) units in a network are
connected by more than one cable, make sure that
these cables are parallel to each other over the whole
distance between those units. When using multi-pair
cable, parallelism is ensured in the best possible way.
Avoid closed loops
Always avoid that intercom cables are making a closed
loop. So-called 'ring intercom' should not physically be
cabled as a ring..
Keep cables away from electromagnetic sources
Keep intercom cables away from high energy cables,
e.g. 115/230/400V mains power or dimmer controlled
feeds for spotlights. Intercom cables should cross high
energy cables at an angle of 90º only. Intercom cables
should never be in the same trunks as energy cables.
Place power supply in a central position
In case of a system powered by a separate power
supply: In order to diminish power losses, place the
power supply as close as possible to where most
power consumption occurs, in other words most user
stations are placed.
ASL powered units to a 'clean' mains outlet
Master stations or power supplies should be
connected to a mains outlet with a clean earth. Other
audio equipment may be connected to this mains
outlet, but avoid using an outlet which also powers
dimmer controlled lighting systems.
In case of more complex installations, don't hesitate to contact us. Please send us a block diagram of the planned
network with a list of all user stations and their positions, and we are happy to advise you on cabling lay out.

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User Manual PS 19M / Issue 2011 © ASL Intercom BV
11.0 PS 19 BLOCK DIAGRAM
12.0 SYSTEM CONFIGURATION

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User Manual PS 19M / Issue 2011 © ASL Intercom BV
13.0 EARTHING CONCEPT