JDM
®
4 Zone Public Address Amplifiers
4
REAR PANEL CONTROLS
1. AC POWER
2. IMPEDANCE
This is for selecting the impedance of the high impedance
speaker terminals.
3. DC 24V TERMINAL
This terminal is for connecting the 24V battery for battery
operation.
WARNING: Ensure the correct battery polarity to prevent
damage to the amplifier.
4. FUSE HOLDER
This fuse holder contains the power fuse(T 2AL 250V). Ensure it
is replaced with same type of fuse when it blows. If it
continuously blows, there may be an amplifier fault. Please
contact a qualified service technician.
5. ANTENNA
Only fitted when either a tuner (A4344A) or CD (A4346) module
is installed. See Fig 4 for wiring.
NOTE:
The picture of the amplifier’s rear panel above shows the
antenna terminal in place. This section of the amplifier’s rear
panel is blocked by a removable ‘knock-out’ section of metal
plate, which needs to be punched out and removed in order for
the antenna terminal to be screwed in place.
6. M.O.H (MUSIC ON HOLD)
Used for connecting to the telephone system when a tuner or CD
module is installed.
NOTE:
The tuner or CD player output volume for music on hold
is set at a fixed level, and is not adjustable via the front panel or
module volume controls.
7. REMOTE CHIME
When these terminals are shorted, the chime is activated.
8. TEL IN
These terminals are for connection to a telephone system for
paging. Use an Austel approved line isolation unit with this input.
NOTE:
When paging, all other input signals except AMP IN are
muted.
9. CH2-4 INPUT SOCKETS
These are for microphone or line inputs. Microphone input
sensitivity and impedance is 3mV/600 ohm. Line input is
300mV/50k ohms.
The XLR sockets of channels 2 and 3 have been designed for
Mic or Line input. Use the switch beside the XLR socket to
accommodate either.
NOTE:
Pin 1 on the XLR and the Sleeve on the phone jack are
grounded.
10. MUTE
This adjusts the muting level when a signal is muted by MIC1,
CHIME or SIREN.
11. LINE–MIC
Set this switch to the desired input type. On CH4, it will switch
between XLR and RCA input options.
12. LINE–PHONO
This channel 5 input is for a magnetic cartridge turntable or a line
level input via RCA jacks, such as a cassette deck, CD/DVD
player etc.
13. LINE–PHONO
Set this switch to the desired input type for channel 5.
14. PRE AMP OUT–AMP IN
This jack is for connecting line level output signal to external
amplifier or a signal processor such as an equalizer.
15. SPEAKER TERMINALS
Refer to the speaker connection terminals Fig. 3a, 3b and 3c
WARNING.
• DO NOT connect speakers to more than one terminal
type. That is, connect only to the four ohm, or only to the
eight ohm, or only to the high impedance terminals.
• DO NOT connect speakers to the four ohm or eight ohm
terminals where the power rating of the speakers is less
than the power rating of the amplifier.
• For the high impedance terminals DO NOT connect
speakers where the total impedance is less than the rated
impedance (see Fig. 3c). Failure to follow this may result
in damage to the amplifier and / or speakers.
16. PHANTOM POWER
These dip switches provide CH2 and CH3 with phantom power
for condenser microphones.
IMPORTANT: When using phantom power, turn the CH2 and
CH3 volume control knobs on the front panel anti-clockwise
to decrease the level, so as to avoid damaging the speakers.
Fig 2:
Rear Panel Layout
