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18
2
INSTALLATION AND CONNECTIONS
2
■
External antenna tuner connection
CONNECTING THE AH-4/AH-3
The AH-4 or AH-3 must be connected to
[ANT1]
.
Coaxial cable (from the AH-4 or AH-3)
ANT1
Control cable
Transceiver
Ground
AH-4 or AH-3
Long wire or optional AH-2b
(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. 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])
[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
■
Microphone connector information
When 2 to 13.8 V is applied to pin 6 of
[ACC(2)]
, the
[XVERT]
jack is activated for transverter operation
and the antenna connectors do not receive or trans-
mit any signals. (p. 20)
While receiving, the
[XVERT]
jack can be activated
as an input terminal from an external transverter.
While transmitting, the
[XVERT]
jack outputs signals
of the displayed frequency at –20 dBm (22 mV) as
signals for the external transverter.
Transverter jack
■
Transverter jack information