Lectrosonics DMTH4 - Manual (Page 7)

Installation Guide
Rio Rancho, NM 7
DM In
+
-
Source
+
Unbalanced source to DM input
(3-Wire)
Shield
DM In
+
-
Source
+
Unbalanced source to DM input
(2-Wire)
Shield
Balanced source to DM input
(3-Wire)
DM In
+
-
Source
+
-
Shield
Installing the DM system into a rack
The DMTH4 occupies a single space. There are no
special ventilation requirements. Mount with 4 rack
screws using the appropriate mounting holes. It is rec-
ommended to use nylon washers to prevent damage to
the front panel’s finish when tightening the screws.
For North American installations, connect the Power
Cable supplied with the unit between the DMTH4 and
a stable power source. All DM processors have inter-
nal switching power supplies that can tolerate voltages
ranging from 100 VAC to 240 VAC. Use an approved
power cable for installations outside North America.
Cables
It is recommented to use lacing bars for cable strain
relief when mounting in a rack. Use only professional
audio cable with proper shielding - typically, two con-
ductor plus ground/shield.
Audio Connections
The analog audio inputs and outputs are connected
through 5 pin de-pluggable connectors. Strip the insu-
lation back 1/8 to 3/16” but do not tin (apply solder to)
the leads. Insert the wire into a de-pluggable connec-
tor, leaving less than 1 mm of bare wire exposed, then
tighten the retaining screw.
Caution: Do not over tighten the retaining
screw.
Note the labeling on the DMTH4 Chassis for the posi-
tive and negative leads. Ground is shared between two
connections (the center pin).
Note: The DM Series does not have a “pin 1
problem.” Inputs and outputs are true differential
connections.
Audio Inputs (AUX and CODEC)
Unbalanced Sources
Unbalanced audio sources (positive and ground)
include items such as consumer VCR’s, DVD players,
etc., and may use both two wire and three wire cables.
In either case, the positive output from the source
should be connected to the appropriate positive (+)
input on the DMTH4. The shield or negative (–) output
should be connected the DM’s negative (–) input. Two
wire cables should have a jumper between the DMTH4
negative input and ground. Three wire cables should
have the shield connected to the DMTH4’s ground input
and the shield and negative (–) leads joined together at
the unbalanced source end.
Balanced Sources
Balanced differential sources from external equipment
and microphones should be wired according to Bal-
anced source to DM input (3-Wire). (See illustration.)
When connecting balanced sources to the DMTH4, it
is important to not connect chassis ground (shield) to
either signal conductor.
Hardware Installation
5-pin depluggable
connector
Do not leave more than
1 mm of exposed wire
beyond the connector.
Do not apply
solder to leads
Retaining Screw
(Do not overtighten)