Extron electronic VLM 2000 - Manual (Page 12)

VoiceLift ™ Microphone • Operation and Features 2-2
Operation and Features
PRELIMINAR
Y
Functional Overview of the VoiceLift Microphone
The VoiceLift Microphone is a soundfield system, which is a low-power classroom
amplification system that ensures that the teacher can be clearly heard at a
comfortable level throughout the classroom.
The pendant microphone, worn by the teacher/speaker, picks up speech and
transmits it via IR signal to the receiver. From the receiver, the signal is fed to
a PoleVault switcher/amplifier, which powers strategically placed speakers to
improve the signal-to-noise ratio of the teacher’s voice to at least +15 dB.
Audio signal transmission
The VoiceLift Microphone components process an audio signal as follows:
OUT IN
O N 1 2
CTS-
2
MI X TO
NE RS-232
AU X IN
CT
C
+
RL Y
Tx
IN
Rx
C
NO
OUT IN
VoiceLift
Adapter
PoleVault Switcher
L R
AUX/MIX IN
1B
1A
I
N
P
U
T
S
O
U
T
P
U
T
S
2B
2A
4
3
RS-232 MLC/IR
DC VOL
4/8
Ohms
AMPLIFIED OUTPUTS
VOL/MUTE
Tx
A B C
Rx IR 12V
10V
POWER
12V
3A MAX
US
LISTED 17TT
AUDIO/VIDEO
APPARATUS ®
RGB VIDEO RGB
VIDEO
STEREO ON
DUAL
MONO
HIGH
PASS
FILTER
OFF
ON
VLR 102 SR
Secondary Receiver
(optional)
Out In
VLR 102
Receiver
VLP 102
Pendant
Microphone
MLC
Controller
Connection
1
2
3
4
VoiceLift Microphone connections and signal path
a
Pendant microphone — The VLP 102 pendant microphone picks up speech
from the instructor and transmits a mono audio signal via IR on the selected
channel (2.3 MHz or 2.8 MHz).