Microphone (Hm-36); Panel Description - Icom ic-718 Instruction Manual

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PANEL DESCRIPTION

 Microphone (HM-36)
q UP/DOWN SWITCHES [UP]/[DN]
Change the selected readout frequency or Memory
channel.
• Holding down continuously changes the frequency or
Memory channel number.
• The [UP]/[DN] switch can simulate a key paddle. Preset
in CW PADDL in the Initial Set mode. (p. 31)
• MICROPHONE CONNECTOR
(Front view)
q Microphone input
w +8 V DC output
e Frequency up/down
• HM-36 SCHEMATIC DIAGRAM
8
q
w
i Main readout AF output
(varies with [AF]/[BAL])
u GND
(Microphone ground)
y GND (PTT ground)
t PTT
r Main readout squelch switch
Microphone
22 kø
+
0.33 µF
4700 pF
1 kø
MIC +
10 µF
ELEMENT
DOWN
PTT
RECEIVE 470 ø
TRANSMIT
w PTT SWITCH
Push to transmit, release to receive.
[MIC]
FUNCTION
PIN NO.
w
+8 V DC output
Frequency up
e
Frequency down
Squelch open
r
Squelch close
CAUTION: DO NOT
can damage the internal 8 V regulator. DC voltage is
also applied to pin 1 for microphone operation. Use
caution when using a non-Icom microphone.
Microphone Plug
Microphone Cable
q u
w i
UP e t
r
DESCRIPTION
Maximum 10 mA
Ground
Ground through 470 
"LOW" level
"HIGH" level
short pin 2 to ground as this
y