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17
4
CONNECTION AND MAINTENANCE
■
Optional UT-105 and UT-108
installation
The optional UT-105 and UT-108 units install as follows:
q
Turn power OFF, then disconnect the DC power cable.
w
Unscrew the 4 screws, then remove the bottom cover.
e
Install the unit as shown in the diagram below.
r
Replace the bottom cover and screws, then the DC power
cable.
■
Optional UT-109 /UT-110
installation
q
Turn power OFF, then disconnect the DC power cable.
w
Unscrew the 4 screws, then remove the bottom cover.
e
Cut the print pattern on the PCB at the TX mic circuit (A)
and RX AF circuit (B) as shown in the following figure.
r
Install the scrambler unit as shown in the left.
t
Return the bottom cover and screws to the original posi-
tion.
NOTE:
Be sure to re-solder
above disconnected points, oth-
erwise no TX modulation or AF
output is available when you
remove the scrambler units.
A
B
Front panel
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