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9
2
PANEL DESCRIPTION
• MICROPHONE CONNECTOR
(Front panel view)
• HM-36 SCHEMATIC DIAGRAM
CAUTION:
DO NOT
short pin 2 to ground as this
can damage the internal 8 V regulator.
NOTE:
DC voltage is applied to pin 1 for micro-
phone operation. Take care when using a non-Icom
microphone.
y
GND (PTT ground)
t
PTT
r
Main readout squelch switch
q
Microphone input
w
+8 V DC output
e
Frequency up/down
u
GND
(Microphone ground)
i
Main readout AF output
(varies with [AF]/[BAL])
■
Microphone
(HM-36)
q
UP/DOWN SWITCHES [UP]/[DN]
Change the selected readout frequency or memory
channel.
• Continuous pushing changes the frequency or memory
channel number continuously.
• While pushing [XFC], the transmit readout frequency can
be controlled while in spilt frequency operation.
• The [UP]/[DN] switch can simulate a key paddle. Preset
in the keyer set mode. (p. 43)
w
PTT SWITCH
Push and hold to transmit; release to receive.
q
w
+
+
q
w
e
r
t
y
u
i
4700p
4700p
10
µ
0.33
µ
MICROPHONE
MIC
ELEMENT
2k
470
DOWN
UP
PTT
RECEIVE
TRANSMIT
MICROPHONE CABLE MICROPHONE PLUG
[MIC]
FUNCTION
DESCRIPTION
Pin No.
w
+8 V DC output
Max. 10 mA
e
Frequency up
Ground
Frequency down
Ground through 470
Ω
r
Squelch open
“Low” level
Squelch closed
“High” level
IC-756PROII.qxd 02.1.8 15:51 Page 9