Parts List

Table Of Contents
2-12
Transmitter Main Board Instruction Manual
with
the
voice
signals to be output from the standard
Modulation
Output port
while
Subtone 2 is
not used. Both subtone inputs
have
an input
level
control.
2.3.4.9
Audio Processor Direct Modulation Input
The Direct Modulation Input is an
extremely
versatile
input. This port is designed to be used for
data signals. Depending on the
application,
the signal can be
amplified,
AC or DC coupled and
output to the
Modulation
Output or the Low Frequency / Direct
Modulation
Output port. Please
consult the factory for
specific
jumper settings for your
application.
2.4 MT-3 Audio Processor (Version 1.8)
invisible
text
2.4.1
General
The MT-3 Audio Processor is a
versatile
circuitboard
that can
provide
several
types of audio
processing for
voice
or data transmission. Two analog
switches
on the audio processor,
controlled
by a common
signal,
make it possible to
transmit
voice
or data. A continuous
+9.5
Vdc supply
and a
switched
+8.0
Vdc supply are required to power the module. The MT-3 Audio Processor is
backwards
compatible
to Daniels
Electronics
MT-2 series
transmitters.
Refer to section 5.5.1
"MT-3 Audio Processor
Component
Layout" and to section 5.5.2 "MT-3 Audio Processor
Schematic
Diagram" for
component
location
and designation
references.
2.4.2
Power Requirements
The audio processor can be configured for continuous audio standby or for
switched
audio standby
by the
Transmitter
Main Board. If fast audio
risetime
is
desired,
the
transmitter
should be
operated
in standby mode 2 or 3 as
specified
in section 2.1.2.7
with
JU36 on the audio processor in the 'y'
position. Power for the
microphone
input and the
balanced
input can be disabled by jumpers JU36
and JU40
respectively
if the input is not required. This results in a current savings of
approximately
3.5 mA per input. The current
requirements
for the MT-3 Audio Processor are
shown in
Table
3-1. The current for the
associated
TOT is
approximately
4 mA when the
transmitter
is keyed. The keyed
values
in the
table
below do not
include
the current for the TOT.