■
Microphone connector information
(Front panel view)
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. Use caution when using a non-
Icom microphone.
■
Microphones (options)
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 split frequency operation.
• The [UP]/[DN] switch can simulate a key paddle. Preset
in the keyer set mode. (p. 4-12)
w
PTT SWITCH
Push and hold to transmit; release to receive.
e
PTT LOCK SWITCH (available for SM-20 only)
Push to toggle between transmit and receive.
2-10
2
INSTALLATION AND CONNECTIONS
[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
y
GND (PTT ground)
t
PTT
r
Squelch switch
q
Microphone input
w
+8 V DC output
e
Frequency up/down
u
GND
(Microphone ground)
i
AF output (varies with [AF])
D
SM-20
D
HM-36
q
w
q
w
e
