JDM
®
4 Zone Public Address Amplifier
REAR PANEL CONTROLS
1. AC POWER INPUT.
2. FUSE HOLDER
This fuse holder contains the power fuse (T 4AL 250V).
Ensure it is replaced with same type of fuse when it blows. If
it continually blows, there may be an amplifier fault. Please
contact a qualified service technician.
3. DC POWER 24V/20A
This terminal is for connecting the 24V battery for emergency
operations.
WARNING: Ensure the correct battery polarity to prevent
damage to the amplifier.
4. SPEAKER ZONES
Refer to the speaker connection terminals figures 3a and 3b.
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. 3b). Failure to follow this may result
in damage to the amplifier and / or speakers.
5. MESSAGE PRIORITY
Not Supported in Australia
6. ANTENNA
Only fitted when either a tuner (A4344A) or CD (A4346)
module is installed. See Fig 4 for wiring.
NOTE:
The picture of the amplifierʼs rear panel above shows
the antenna terminal in place. This section of the amplifierʼs
rear panel is blocked by a removable ʻknock-outʼ section of
metal plate, which needs to be punched out and removed in
order for the antenna terminal to be screwed in place.
7. MIC(XLR) / LINE(PHONE) INPUTS
These are for microphone or line inputs CH1 to CH5.
Microphone input sensitivity and impedance is 3mV/600 ohm.
Line input is 300mV/50k ohms.
The XLR / Phone jack combined sockets have been designed
for Mic or Line inputs without the need for switches.
Note:
Pin 1 on the XLR and the Sleeve on the phone jack are
grounded, as per the diagrams on the rear panel.
8. MUTE
These knobs adjust the muting levels of inputs CH1 and CH2.
9. PRIORITY / (PHANTOM POWER)
Two of the four dip switches provide CH1 and CH2 with
phantom power for condenser microphones. The other two
switches activate priority muting for the same two channels.
IMPORTANT:
When using phantom power, turn the CH1 and
CH2 volume control knobs on the front panel anti-clockwise
to decrease the level, so as to avoid damaging the speakers.
10. PRE OUT
This jack is for connecting line level output signal to external
amplifier or a signal processor such as an equalizer.
11. AMP IN
This input is for a direct signal from external equipment (+4dB
level). It is controlled by the MASTER volume knob on the
front panel.
12. REMOTE CHIME terminal
When these terminals are shorted, the chime is activated.
13. REMOTE SIREN terminal
When these terminals are shorted, the chime is activated.
14. 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.
15. HIGH IMPEDANCE SWITCH
This switch is for selecting the impedance of the high
impedance speaker terminals (70V or 100V).
1 2
3
9
8
7
14 13 12
11
10
6
5
4
BALANCED OUTPUT
(20 ) 70V
100V(42 )
MESSAGE
E/M CON
HIGH IMPEDANCE
DIRECT
OUTPUT
SPK ZONES
CLASS 1 WIRING
FUSE RATING
T4AL 250V
CLASS 2 WIRING
8
LOW
25V
HIGH
1
2
3
4
(2.6 )
70V
100V
( )
HOT
COLD
CAUTION:
TO REDUCE THE
RISK OF FIRE REPLACE ONLY
WITH SAME TYPE FUSE.
DC POWER
24V/20A
MODEL.: T
A-1240
MADE IN KOREA
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
WA
RN
IN
G:
TO REDUCE THE RISK OF FIRE
OR ELECTRIC SHOCK DON'T EXPOSE THIS
EQUIPMENT T
O
RAIN OR MOISTURE.
MIXING AMPLIFIER
300
AM GND
FM 75
AMP IN
PRE OUT
MASTER
CLASS 2
MIC
S (GND)
T ( )
R ( )
S R T
LINE
G
1
2
3
5
4
3
2
CHIME
REMOTE
SIREN
TEL IN
1
MIC(XLR) / LINE(PHONE) INPUTS
30
20
10
50
1
2
30
20
10
50
P.H
P.H
LINE
MIC
LINE
MIC
H.A
H.A
RMS 240W
PRIORITY
PRIORITY
AC230~50Hz 625W
JD-MEDIA CO
.,L
TD
.
15
Fig 2:
Rear Panel Layout
4
