Tait TM8100 mobiles, Service Manual

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TM8100/TM8200 Service Manual Description 27
© Tait Electronics Limited November 2007
2.1.2 Control Head with Graphical Display
Overview
The control head can be divided into the following main areas:
■
front panel with control elements, indicators, LCD, speaker, and
concealed microphone (optional)
■
space frame and seals
■
control-head board with SMT components, shielding cans, connectors,
and volume potentiometer
■
control-head loom with female-female adapter
■
adapter flange.
The circled numbers in this section refer to the items in Figure 2.4 on
page 29 .
Front Panel
Assembly The front panel assembly
1^
consists of an injection-moulded plastic part
with an integrated transparent light pipe element for the radio
STATUS
LEDs,
a transparent lens which cannot be replaced, a cloth membrane which is
fixed to the speaker grille, and a foam seal inside a rectangular LCD recess
behind the lens. A label
1*
with the radio model number is attached to the
front panel assembly with self-adhesive coating and can be replaced for
rebranding purposes.
Three clips on the rear side of the front panel assembly snap onto the space
frame to hold the keypads
1#
and
1#
, the LCD assembly
1@
and the speaker
1!
in place. The rear side of the front panel assembly also has four screw
bosses to fasten the control-head board
F
.
Knob for
Volume-Control
Potentiometer
The knob for the volume-control potentiometer
1&
is fitted to the shaft of
the volume-control potentiometer, which is soldered to the control-head
board
F
.
Keypads
The main keypad
1#
(for the function, selection, and scroll keys) and the
power keypad
1$
protrude through apertures in the front panel assembly
1^
.
The rear sides of these keypads connect directly to the relevant contacts on
the control-head board
F
.
LCD Assembly
The graphical-display LCD assembly
1@
sits on a foam seal inside a
rectangular recess of the front panel assembly
1^
. Another foam seal is
attached to the rear of the LCD with self-adhesive coating. The LCD
assembly has a loom, which runs through a slot in the space frame
J
and
connects to a connector on the rear side of the control-head board
F
.