1
Loop amplifier
LAX50
Instructions for use
FEATURES
Up to 50m
2
coverage
2 Inputs
Phantom Power
Current Mode Output
Integrated PSU
Soft Start
Compressor
Noise Meter
True Operation Indicator
Protected Mix Control
Protected Output Drive Control
Power Indication
3A Peak Current Capability
DESCRIPTION
The
LAX50
is part of PASO range of audio frequency induction loop (AFILS) amplifiers.
The unit is designed for user-friendly installation to walls, vanity panels, desks and counters. The unit is compact, the front is printed with the
AFILS logo as well as text boxes to allow the name of the responsible person and their contact number to be written in. The controls (Mix and
Drive) are recessed to hinder unauthorised adjustment, and LED indication is provided for the presence of power and loop current.
The amplifier has two inputs to accept microphones and other signals adapted to such level. The inputs are mixed together and the balance
between the two inputs is set with the mix control, this allows the unit to operate with a main microphone and an ambience microphone if
required, or in a TV lounge to allow a scart connection to the television to be balanced with an ambience microphone for conversation. The unit
incorporates the latest design in audio processing allowing varying microphone levels to be compensated for automatically while preventing any
sudden loud noises from reaching the output stage. The compressor design automatically adjusts the release time providing high quality music
with a slow release and speech with a relatively fast release. The compressor ratio is dynamically variable and will automatically change from
1:1 to over 20:1 in the case of limiting. The unit also provides an automatic noise suppression system, reducing the level of audible hiss from
the compressor as gain is added to the system. The output stage for the LAX50 incorporates a true constant current design, which will drive loop
coils from 0.1
Ω
to 1
Ω
and is specifically designed for single turn loops in rooms. The output level is set using the drive control and is protected
against over temperature and DC offset and has a soft start facility removing loud clicks and pops when the unit is turned on.
INSTALLATION
The LAX50 is designed to provide loop coverage for counters, desks and interview rooms, as well as larger areas up to 50 m
2
(see note 1). To aid
installation, a range of accessories are available including pre-made telecoils, loop cable, discrete clip microphones and scart adapters. Installation is
simplicity itself, the unit should be sited in a convenient place (ideally as close to the area to be covered as possible) the loop cable (a single turn loop of
between 0.5 mm and 1.5 mm CSA cable) or telecoil is installed securely (see note 2) and the microphone(s) are located as close to the area(s) where the
sound is to be picked up from (see note 3). Mains power can now be applied using the cable supplied, the output drive control and microphone
mix controls can now be adjusted to the users preference. This is best done with a loop field strength meter during installation, or a loop
listening device (good practice is to supply a loop listening device to all installations to allow the responsible person to test the loop
periodically and record correct operation in a log booklet). The loop can consist of either cable, or a pre-made telecoil. The latter is ideal for
quick installation to bank counters and ticket offices and should be placed as close to the customer as possible. The telecoil produces a field
about 1.2m in diameter allowing them to be placed on alternate serving positions in densely populated bank halls. If the area to be covered
is larger than that covered by the telecoil, then a single turn wire loop should be employed.
APPLICATIONS
The following are a few examples of the
uses for the
LAX50
AFILS amplifier,
including the likely accessories required.
Counters
Using the telecoil, with either the clip
or desk microphone
Interview Room
Using the telecoil on the desk, with
the desk microphone
Meeting Rooms
Using a loop cable and either desk or
clip microphone(s)
TV Lounges
Using a loop cable and Scart lead, with
optional microphone
Sheltered Housing
Using loop cable, clip microphone and
doorbell interface
POWER SUPPLY
This equipment is designed for use with a mains voltage of 230 V ± 10% 50/60 Hz. The LAX50 is supplied with its own power-supply cable, which is
equipped with an earthing wire. The earth terminal of the mains plug should never be removed under any circumstances. Connect the mains plug of
the LAX50 to the power mains using the cable included in the supply. Make sure that the power outlet is equipped with a connection to earth in
accordance with the law.
The replacement of fuses must be carried out by specialized personnel only: when the cover is removed, parts liable to cause electric shocks are
exposed. Before removing the cover, always make sure that the power cord has been disconnected. In the event that liquid is accidentally spilt
onto the equipment, disconnect the mains plug immediately and contact the nearest PASO Service Centre.
SAFETY NOTES
