•
•
•
3
-
4
-
2 L ED I N D I CATO R C I R CUIT
is
L E D
is lit in the
transmit mode, but when the power supply voltage becomes less than 5. 5V, it will
ot be lit.
e power supply voltage is divided by R148 and R149, and applied to the base of 0121. The emitter
o
0121
is
connected to
the regulated 5V source. When the power supply voltage is more than 5. 5V,
121
is turned
O F F, 0122
is
turned O N and T+5V is applied to the L E D through 0122 and R150, and
E
is
Ii
.
3
-
4
-
3 DIODE MAT R I X BOA R D
e se
·
corporates a diode
matrix
board to determine its operation frequencies, and twelve channels
-
be
progra med into the board.
-5
i
s app
l
i
ed o
a
channel line,
one of channel 1 �channel 12, through the channel select switch, and
ed to B C D codes by diodes programmed into the board, then fed to IC201 to determine an
equency (channel) .
a
s
nc ion is
provided
by inserting a diode into the duplex line on the board. At this
·s
a p
l
i
ed o he
base
of 0402, and turns
0402
and 0401 ON. Thus T+ 5V is applied to
a
�
ects
X204. and he
transmitting frequency
shifts
specified offset frequency.
ece
·
.
e
:.:ge
·
s ap
06
FF
.
is provided by inserting a diode into the receive only line. At this time, a
o
t e base
of 0107 on the MAIN board through R404, and it turns 0107 ON and
e se does not turn to the transmit mode, even if the PTT switch is depressed .
3-4
