Icom IC-720A Instruction Manual page 13

is in the RF position.
39. METER SWITCH
When the METER SELECT switch on the front panel is in
the RF position, this switch is used to select indication of
the collector current of the final transistors, or relative
output power.
40. CW DELAY CONTROL
In semi-break-in operation, this controls the transmit/receive
switchover time-delay. Adjust to suit your keying speed.
(Note: If the delay is set to the shortest position, it will
reach almost full break-in CW.)
41. ANTI-VOX CONTROL
In VOX (SSB and AM) operation, the VOX circuit may be
operated by sound from the speaker causing a switch to
4-3 REAR PANEL CONNECTIONS
@RECEIVER INPUT TERMINAL
@RECEIVER ANTENNA OUTPUT TERMINAL
НЕМЕ ANT LOW SANE лит 2-TERTER/ SCOPE:
чи MO
"Е
2h
@EXTERNAL SPEAKER JACK
@KEY JACK
ANTENNA CONNECTOR
GROUND TERMINAL
44. RECEIVER INPUT TERMINAL
This is an input terminal which is connected directly to
the receiver.
45. RECEIVER ANTENNA OUTPUT TERMINAL
This is a terminal to which received signals from the anten-
na connector are conducted after the signal passes through
the transmit/receive antenna switching circuit. Usually the
receiver IN and OUT terminals are jumpered. The receiver
antenna output terminal is usually used when another
receiver is used or a pre-amplifier is connected to the
ІС-720А.
46. EXTERNAL SPEAKER JACK
When an external speaker is used, connect it to this jack.
000009 |
0000001 „е;
собопо |
000000 |
ú z
+ па |
—10—
transmit. This trouble can be prevented by adjusting the
input level of the ANTI VOX circuit with this control along
with the VOX gain control so that the VOX circuit only
operates from the operator's voice, not by sound from the
speaker.
42. VOX GAIN CONTROL
This control adjusts input signal level via the microphone to
the VOX circuit. For VOX operation in SSB and AM, ad-
just the control so that the VOX circuit will operate with
normal speech.
43. SWR SET CONTROL
This control calibrates the meter needle to the Po SET
position when you want to determine the value of SWR.
The METER SELECT switch must be in the RF position
and the set must be transmitting a carrier.
@LOW BAND ANT (RL) TERMINAL
S) TRANSVERTER SCOPE (ALC)
TERMINAL
52 ACCESSORY SOCKET
POWER SOCKET
"FUSE HOLDER
6)}MEMORY BACK UP
POWER SOCKET
Use a speaker with an impedance of 8 ohms. When the
external speaker is connected, the built-in speaker does
not function.
47. KEY JACK
For CW operation, connect the key here. For electronic
keying the terminal voltage must be less than 0.4V DC.
48. ANTENNA (ANT) CONNECTOR
This is used to connect the antenna to the set. Its imped-
ance is 50 ohms and connects with a PL-259 connector.
49. GROUND TERMINAL
To prevent electrical shock, TV!, BC! and other problems,
be sure to ground the equipment through the GROUND