Icom HM-169 Service Manual page 12

• MAIN-B UNIT (for [HM-170GP], [HM-175GPS])
MICROPHONE
CHASSIS UNIT
GPS ANTENNA
ANT 3.3V
Serial LELEV
TX SHIFTER
GPS IC13, IC6
Serial
RX
PPS Sleep
IC4
PTT
(HM-175GPS)
RIPPLE
FILTER
(HM-170GP)
Q3, C14
MIC
MIC
AMP MUTE
IC2
IC14, Q6
(HM-175GPS)
LEVEL
SHIFTER
D6
(HM-170GP)
D4
GPS
ON/OFF
IC9, IC10
(HM-175GPS)
(HM-175GPS)
(HM-170GP)
SPEAKER
+3.3V
SWITCHING
REG
IC8, Q5, D5, L3
(HM-175GPS)
+3.3V
IC11
(HM-175GPS)
RESET
SW UNIT (HM-175GPS)
Q4
+3.3V
(HM-175GPS)
LED
DRIVER
DS1
SW1
SW UNIT (HM-170GP)
SW1
6 - 2
(HM-170GP) (HM-175GPS)
1 SP- SP-
2 SP+
SP+
3 Vcc Vcc
4 MIC MIC
5
NMEA NMEA
6 XTXD SENS
7 GND
GND
8 PTT nc