ASL INTERCOM PS 130, Руководство пользователя

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User Manual PS 130 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland.
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8.0 PARTY LINE, TECHNICAL CONCEPT 10.0 TECHNICAL SPECIFICATIONS PS 130
ASL's PRO Series offers a complete two way ('full duplex')
communications system.
current (at 30 V DC) 35 mA quiescent
Users of the system are connected via a 'party line'. 70 mA signalling
Master stations (with built-in power supply), beltpacks, 190 mA at max. signalling
speaker stations and power supplies are interconnected
via standard microphone cable. One wire is used as an
audio line, one as a power line and the screen of the cable
gooseneck microphone type noise cancelling electret
functions as earth/return. headset mic. impedance 200 ohms
Current drive is used for signal transfer. Each station presence filter +6 dB at 5 kHz
utilises a current amplifier to amplify the microphone signal frequency response 200 Hz - 13 kHz (-3 dB)
and place it on the common audio line where, due to the V electret mic +9 V DC
constant line impedance (situated in the power supply
between XLR pin 3 and 1), a signal voltage is developed
which can be further amplified and sent to headphones or
max. load 200 ohms
loudspeakers. max. output level 14 V rms (200 ohms)
This principle has three advantages:
-
the use of a single audio line allows several stations to
talk and listen simultaneously.
speaker impedance 50 ohms
- due to the high bridging impedance offered by each max. output power 1.3 W rms
station, the number of stations 'on line' has no
influence on the level of the communications signal.
- power and audio to the intercom stations use the same max. output current 3 mA rms
cable. output impedance > 150 Kohms
The Call signal is also sent as a current on the audio line.
It develops a DC potential over the line impedance which
rejection 0 - 30dB adjustable
will be sensed by each station and interpreted as a Call
signal.
9.0 GUARANTEE
This unit is warranted by ASL Intercom to the original end-
user purchaser against defects in workmanship and
materials in it's manufacture for a period of one year from
date of shipment to the end-user.
Faults arising from misuse, unauthorised modifications or
accidents are not covered by this warranty. If the unit is
faulty it should be sent in it's original packing, to the
supplier or your local ASL dealer, with shipping prepaid. A
note must be included stating the faults found and a copy
of the original suppliers invoice.
THIS PRODUCT WAS DESIGNED, DEVELOPED AND
MANUFACTURED BY:
AMPCO SOUND LAB BV
MAARSSEN (UTRECHT) HOLLAND.
POWER CONSUMPTION
MIC. PREAMP
gain 40 dB - 70 dB (adjustable internally)
HEADPHONES DRIVER AMP
max. output power 0.5 W rms (each can)
SPEAKER DRIVER AMP
INTERCOM LINE DRIVER
SIDETONE
BUZZER
max. SPL
100 dBA
DIMENSIONS AND WEIGHT
width
230 mm
height 88 mm
depth 42/48 mm sloping
weight 1.1 Kg
GENERAL SYSTEM SPECIFICATIONS
intercom line impedance
350 ohms (1kHz)
2.2 Kohms (DC)
intercom line audio level nom. -18 dBu
max. +4 dBu
dynamic range 80 dB
call send signal +2.8 mA
call receive signal threshold +2.4 V DC
supply voltage +30 V DC (12 V to 32 V)
mic mute power interrupt time 0.1 sec
Note: 0 dBu = 775 mV into open circuit
ASL reserves the right to alter specifications without further
notice.