Icom IC-730 Maintenance Manual page 7

33. VOX GAIN CONTROL
The control adjusts input signal level via the microphone to
the VOX circuit. For VOX operation in SSB, adjust the
control so that the VOX circuit will operate with normal
speech.
34. VOX DELAY (VOX time constant) CONTROL
The controls the transmit to receive switching time. Adjust
it so transmit to receive switching will not occur during
short pauses in normal speech.
35. ANTI-VOX CONTROL
In VOX (SSB) operation, the VOX circuit may be operated
by sound from the speaker causing a switch to transmit.
This trouble can be prevented by adjusting the input level
of the ANTl-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.
36. N.B. WIDTH SWITCH
Switches the blanking action time of the noise blanker
NARROW (short) and WIDE (long). Set the switch in the
NARROW or WIDE position according to incoming noise.
37. CW MONITOR (MONI) CONTROL
This control adjusts the audio volume of the side tone
(monitor) audio during CW transmit operation. Adjust it to
your desired level for easy listening.
38. FREQUENCY SET CONROL
This control is for fine adjustment of the reference frequency
of the PLL unit, which is local oscillator frequency.
Do not turn it unless you want to change the frequency.
39. MEMORY BACKUP (RL) TERMINAL
For connection of a 9 ~ 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
IC-BC10A is recommended.
By changing an internal connector, this terminal can be
used for Transmit/Receive relay control terminal. This
terminal can be used to switch 24V 1A DC. Don 't exceed
this l imit.
40. EXTERNAL ALC TERMINAL
This terminal can be used for input terminal of external
ALC signal from a linear amplifier or transverter.
By using optional adapter, IC-EX205 and changing internal
connectors, this terminal can be used for TRANSVERTER
terminal.
VHF and UHF operation using a suitable transverter with
the IC-730 is possible. This terminal is for Transverter
connection. The output is a few milliwatts.
41. EXTERNAL SPEAKER JACK
When an external speaker is used, connect it to this jack.
Use a speaker with an impedance of 8 ohms. When the external
speaker is connected, the built-in speaker does not function.
42. KEY JACK
For CW operation, connect the key here. For electronic keying
the terminal voltage must be less than 0.4V DC.
43. ACCESSORY (ACC) SOCKET
Various functions are available through the accessory socket
such as modulation output, receiver output, T/R change- over,
and so forth. The table below shows those terminals.
ACC SOCKET CONNECTIONS
PIN No.
1. NC (no connection)
2. 13.8 Volts DC in conjunction with the power
switch operation.
3. Connected to Push-to-talk, T/R change-over
switch. When grounded, the set operates in
the transmit mode.
4. Output from the receive detector stage. Fixed
output regardless of AF output or AF gain.
5. Output from Transmitter MIC amplifier stage.
(Input for MIC gain control stage.)
6. 8 Volts DC available when transmitting. (relay
can not be directly actuated. Max.5mA).
7. Input for external ALC voltage.
8. Ground
9. NC
10. 8 Volts DC available when the 28MHz band is
selected.
11. Input for TRANSVERTER control. When 8
Volts DC is applied, set can operate with a
transverter.
12. Output reference voltage for band switching.
13. Output for external band switching.
14.~24. NC
44. ANTENNA (ANT) CONNECTOR
This is used to connect the antenna to the set. Its impedance is
50 ohms and connects with a PL-259 connector.
45. GROUND TERMINAL
To prevent electrical shock, TV, BCI and other problems, be sure
to ground the equipment through the GROUND
TERMINAL. For best results use as heavy a gauge wire or strap
as possible and make the connection as short as possible, even
in mobile installations.
46. POWER SOCKET
For connection of the I C-PS15's DC power cord, or other
suitable power supply.
2 – 4
Outside view
FUNCTION