Midian DDU-300, Instruction Manual

Page: 4 / 22

P
AGE
4 M
IDIAN
E
LECTRONICS
I
NCORPORATED
DDU-300 Manual Rev. 2006.02.22
2 OVERVIEW
The DDU provides the optimal ANI display decoder
solution for small and medium sized radio systems
such as those used by taxi fleets, police departments,
construction crews, etc.
The last 10 ANI's received can be reviewed at any
time. It can store up to 137 aliases in its user
database. The user friendly menu system makes it as
easy to use as a cell phone. Additional features
include emergency status display and the ability to
automatically mute incoming leading ANI's.
In addition to the decode features, the DDU-300 offers
fleet management functions including selective calling
of units, over the air reprogramming (OTAR), and the
ability to disable units remotely.
3 INSTALLATION INSTRUCTIONS
Installation Note: Midian products utilize CMOS integrated
circuits, which are susceptible to damage from high static
charges. Be sure to follow standard antistatic procedures
when handling, including using grounded workstations and
soldering irons and wearing grounding bracelets.
3.1 R
ADIO
I
NTERFACE
Radio Interface connector P1 is an 8-pin
RJ-45 style connector in the center of the
back panel.
+V IN (P1-5) [Red]
The DDU can be powered either by an optional wall
transformer or by the radio power supply. Connect this
wire to the radio power source provided it is between
12 and 15 VDC.
If using a wall transformer, make sure the voltage is
between 12 and 15 VDC and the current rating is at
least 800mA. Also, be certain that positive is
connected to the inside ring.
GROUND (P1-6) [Black]
Connect to radio ground.
AUDIO INPUT/RX IN (P1-8) [Blue]
Connect to a point in the radio where receive audio is
present at a constant level. If using PL or CTCSS, be
sure to connect to a point after the CTCSS high pass
filter. If using the Squelch Output of the DDU, be sure
the RX audio point is not muted when the squelch
output to the radio is asserted.
AUDIO OUTPUT/TX OUT (P1-4) [Green]
Connect to the mic-hi input of the radio. The output
impedance of the DDU can be adjusted if necessary
by replacing leaded resistor R81 with an appropriate
value.
PTT OUTPUT (P1-3) [Yellow]
This connection is only required if the DDU is
equipped with a microphone or handset.
This open collector output provides a ground to key-up
the radio when transmitting. If connecting to a relay in
the radio, make sure the coil is bypassed with a diode
to eliminate counter-EMF.
This output may also be assigned to be the repeater
access control output. See REPEATER SETUP for
more information.
COR INPUT (P1-1) [Gray]
This connection is only required if using the internal
speaker auto-mute feature, busy lockout, or repeater
access control.
Connect to a point in the radio squelch or CTCSS
circuit that changes logic level when carrier (or
CTCSS) is detected. A radio whose circuitry provides
a logic-low or logic-high can readily turn Q1 on and off.
If only a high level is provided, it may be necessary to
move R40 from its pull-up to its pull-down position.
MONITOR OUTPUT (P1-7) [Orange]
This optional output can be used to control the monitor
function of the radio using the <MONITOR> button on
the DDU. This is an open collector output which
changes state each time the <MONITOR> button is
pressed.
This output may also be assigned to be the repeater
access control output. See REPEATER SETUP for
more information.
SQ OUT/LTR IN (P1-2) [Brown]
This wire may be either a Squelch Output or a
Trunking Delay (LTR) input, but not both. To use as a
squelch output, install jumper R85 and make sure
jumper JU5 is not installed. To use as a trunking delay
input, remove R85 and install JU5.
When used as a Squelch Output, connect to a point in
the radio which will mute the speaker when brought to
ground (or left floating). Program the appropriate
polarity in the RADIO SETUP menu.
When used as an LTR Trunking Delay Input, connect
to a point in the radio which goes from 0 to 5 VDC
when a channel has been acquired on the LTR