Panel Description ........... 1; I Microphone (Hm-36) - Icom IC-746PRO Instruction Manual

I 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. 34)
• MICROPHONE CONNECTOR
(Front panel view)
i Main readout AF output
(varies with [AF]/[BAL])
q Microphone input
w +8 V DC output
e Frequency up/down
r Main readout squelch switch
• HM-36 SCHEMATIC DIAGRAM
q
w
u GND
(Microphone ground)
y GND (PTT ground)
t PTT
MICROPHONE
+ 2k
10µ 4700p
+
0.33µ
MIC
4700p
ELEMENT
DOWN UP
PTT
RECEIVE
470
TRANSMIT
w PTT SWITCH
Push and hold to transmit; release to receive.
[MIC]
FUNCTION
Pin No.
w
+8 V DC output
Frequency up
e
Frequency down
Squelch open
r
Squelch closed
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.
MICROPHONE CABLE MICROPHONE PLUG
q u
i
w y
e t
r
PANEL DESCRIPTION
DESCRIPTION
Max. 10 mA
Ground
Ground through 470 Ω
"Low" level
"High" level
1
12