UM400a
5-Pin Input Jack Wiring
The wiring diagrams included in this section represent
the basic wiring necessary for the most common types
of microphones and other audio inputs. Some micro-
phones may require extra jumpers or a slight variation
on the diagrams shown.
It is virtually impossible to keep completely up to date on
changes that other manufacturers make to their products,
thus you may encounter a microphone that differs from
these instructions. If this occurs please call our toll-free
number listed under Service and Repair in this manual or
visit our web site at: www.lectrosonics.com
10
PIN 1
PIN 2
PIN 3
PIN 4
Audio Input Jack
PIN 5
1
2
3
4
5
The Audio Input Jack for the UM400a is wired as shown
below:
Shield (ground) for positive biased electret lava-
liere microphones. Shield (ground) for dynamic
microphones and line level inputs.
Bias voltage source for positive biased electret
lavaliere microphones.
Low impedance microphone level input for
dynamic microphones. Also accepts hand-held
electret microphones provided the microphone
has its own built-in battery.
Bias voltage selector for Pin 3. Pin 3 voltage (0, 2
or 4 volts) depends on Pin 4 connection.
Pin 4 tied to Pin 1: 0 V
Pin 4 Open:
Pin 4 to Pin 2:
High impedance, line level input for tape decks,
mixer outputs, musical instruments, etc.
100 Ohm
GND
+
BIAS
30uF
MIC
BIAS SELECT
LINE IN
10k
2 V
4 V
+5 VDC
Servo Bias
Pin 4 to Pin 1 = 0 V
Pin 4 Open = 2 V
Pin 4 to Pin 2 = 4 V
30uF
200 Ohm
100 Ohm
To Virtual Ground
Audio Amplifier
To Limiter Control
+
3.3uF
SM Equivalent Input Circuit Wiring
LECTROSONICS, INC.
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