Icom IC-7700

2-12
2
INSTALLATION AND CONNECTIONS
■ Accessory connector information
NOTE: If the CW side tone level limit or beep level limit is in use, the CW side tone or beep tone decreases
fromthefixedlevelwhenthe[AF]controlisrotatedaboveaspecifiedlevel.(p.12-6)
1
2
3
4
5
6
7
8
ACC 1 PIN No. NAME DESCRIPTION SPECIFICATIONS
1
RTTY
Controls RTTY keying
“High level”
“High level”
Output current
:Morethan2.4V
:Lessthan0.6V
: Less than 2 mA
2 GND
Connects to ground.
Connected in parallel with ACC 2 pin 2.
———
3 SEND*
Input/output
pin.
Connected in
parallel with
ACC 2 pin 3.
An external equipment
controls the transceiver.
When this pin goes low,
the transceiver transmits.
Input voltage (High)
Input voltage (Low)
Current flow
:2.0Vto20.0V
:–0.5Vto0.8V
:Max.20mA
The transceiver outputs
alowsignaltocontrolex-
ternal equipment.
Output voltage (Low)
Current flow
:Lessthan0.1V
:Max.200mA
4 MOD
Modulator input.
Connects to a modulator.
Input impedance
Output level
: 10 kΩ
:
Approximately100mVrms
5 AF
AF detector output.
Fixed level, regardless of [AF] position
in
default settings. (see notes below)
Output impedance
Output level
: 4.7 kΩ
:100–300mVrms
6 SQLS
Squelch output.
Grounded when squelch opens.
SQL open
SQL closed
:Lessthan0.3V/5mA
:Morethan6.0V/100µA
7 13.8V
13.8VoutputwhenpowerisON.
Connected in parallel with ACC 2 pin 7.
Output current :Maximum1A
8 ALC
ALC voltage input.
Connected in parallel with ACC 2 pin 5.
Control voltage
Input impedance
:–4Vto0V
: More than 10 kΩ
1
2
3
4
5
6
7
ACC 2 PIN No. NAME DESCRIPTION SPECIFICATIONS
1
8V
Regulated8Voutput.
Output voltage
Output current
:
8V±0.3V
: Less than 10 mA
2 GND Same as ACC 1 pin 2.
3 SEND* Same as ACC 1 pin 3.
4 BAND
Band voltage output.
(Varieswithamateurband)
Output voltage :0Vto8.0V
5 ALC Same as ACC 1 pin 8.
6 TRV
Activates[X-VERTER]input/output
when “HIGH” voltage is applied
Input impedance
Input voltage
: More than 10 kΩ
:2Vto13.8V
7 13.8V Same as ACC 1 pin 7.
* When the SEND terminal controls the inductive load (such as a relay), a counter-electromotive force can cause
the transceiver’s malfunction or damage. To prevent this, we recommend adding a switching diode, such as an
“1SS133,” on the load side of the circuit to the counter-electromotive force absorption.
When the diode is added, a switching delay of the relay may occur. Be sure to check its switching action before
operation.
e SEND
u 13.8 V
ACC 1/2
sockets
Relay
Switching diode
To a non-Icom
linear amplifier
[Example]