Icom IC-720 Instruction Manual page 12

4-3 REAR PANEL CONNECTIONS
@RECEIVER ANTENNA INPUT TERMINAL GLOW BAND ANT (RL) TERMINAL
S)TRANSVERTER SCOPE (ALC)
TERMINAL
RECEIVER ANTENNA OUTPUT TERMINAL
RECEIVE ANT ми иде кат E-VERTER/SCOPE
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1 ЕХТЕВМАЕ SPEAKER JACK
4DKEY JACK
4 ANTENNA CONNECTOR
GROUND TERMINAL
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ӚЭРОМГЕН SOCKET
FUSE HOLDER
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ЭМЕМОНҮ BACK UP
POWER SOCKET
44. RECEIVER ANTENNA INPUT TERMINAL
This is an input terminal which is connected directly to the
receiver.
45. RECEIVER ANTENNA OUTPUT TERMINAL
Received signals are conducted here after passing through
the antenna switching circuit. Normally the receiver in and
out terminals are jumpered, and this terminal is used only
when another receiver is connected, or a pre-amplifier is
connected to the IC-720.
46. EXTERNAL SPEAKER JACK
For connection of an external speaker of 8 ohms. The
internal speaker is disabled when this jack is used.
47. KEY JACK
For CW operation, connect the key here. For electronic
keying the terminal voltage must be less than 0.4V ОС.
48. ANTENNA (ANT) CONNECTOR
This is used to connect the antenna їо the set. Its inpedance
is 50 ohms. Connection must be with a PL259 connector.
49. GROUND TERMINAL
To prevent electrical shock, ТУІ, BCI, and related problems
it is very important that a good ground be hooked up with
as heavy and short a wire as possible. This holds true in
both fixed and mobile installations.
50. LOW BAND ANTENNA TERMINAL (RL)
For connection of a low band antenna.
By turning the internal switch, it can be used as a Tx/Rx
relay control. Switching for this terminal can be accom-
plished with +24V, 1A DC. Do not exceed this limit.
—10—
51. TRANSVERTER SCOPE (ALC) TERMINAL.
1. For connection of a panadaptor or panascope to observe
the 39.7315MHz IF signal of the receiver, and also
signals of a selected bandwidth.
2. Using a suitable transverter VHF and UHF operations"
are possible with the IC-720. The output is a few
milliwatts, refer to the instructions for transverters for
proper hookup. By moving the 2-pin plug this terminal
can be used as an external ALC input, see page 28.
52. ACCESSORY (ACC) SOCKET
External accessories and controls can be used with the
ІС-720, connected to this socket. NOTE: Pin 10, 11, 18 ~
24 are for digital control and are connected to the input of
the C-MOS-IC, do пої арріу any voltages not within 0.5 to
+5 Volts. For details refer to page 20.
53. POWER SOCKET
For connection of the |С-Р5155 DC power cord, or other
suitable power supply.
54. FUSE HOLDER
This holds the fuse for the DC power circuit. If the fuse is
blown, replace it with a new 20 Amp fuse after checking
the cause. Open the fuse holder with a Phillips head driver.
55. MEMORY BACKUP POWER SOCKET
For connection of a9 ~ 12V DC power supply. For mobile
installation connection to the vehicle's battery can be made
the current drain is low, for fixed installation use of the
ІС-ВСТОА is recommended.