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15
4
OPERATION
■
Mode selection
The [RF/SQL] control adjusts either the RF gain or
the squelch. The action depends on the operating
mode and the condition of the RF/SQL item in
initial
set mode (p. 31).
• [RF/SQL] control priority
* The RF gain is set to maximum level when the [RF/SQL]
is set as [SQL] control.
The
RF gain is used to adjust the receiver gain.
• Shallow rotation moves the S-meter to the right indicating
the signal strength which can be received.
The recommended position for RF gain is the 12
o’clock position since this sets RF gain to the max.
The
SQUELCH removes noise output from the
speaker
(closed condition)
when no signal is received.
The squelch is available for the other modes.
• A segment appears in the S-meter to indicate the S-meter
squelch level.
• When set as the [RF/SQL] control
• When set as the [SQL] control
• When set as the [RF] control
■
RF gain and Squelch
Set mode setting SSB, CW, RTTY
AM
rS (RF/SQL)
RF/SQL
RF/SQL
At (Auto)
RF gain
SQL*
Sq (SQL)
SQL*
SQL*
(default)
RF gain adjustable
range
Maximum RF gain
Squelch is open.
S-meter squelch
S-meter squelch
threshold
Squelch is open.
S-meter squelch
S-meter squelch
threshold
Shallow
Deep
Minimum RF gain
Adjustable range
Maximum RF gain
■
Basic voice receive and transmit
q
Check the following in advance:
➥
Microphone is connected.
➥
[AF] control is set to minimum position.
➥
[RF/SQL] is set to center position (squelch open).
➥
[RIT] control set to center position.
w
Selects the desired channel to be received with the
channel selector, [
√
DN]/[UP
∫
], or 10-key pad.
• The S-meter shows signal strength when signal is received.
e
Adjust [AF] to the desired audio level when receiv-
ing a signal.
r
Push [MODE] to select the desired operation mode,
if the received signal is in a different mode.
t
If the bass or treble of the receive audio is too
strong, rotate [RIT] control to obtain clear audio.
(p. 19)
y
Push [TUNER] to tune the antenna tuner, if connected.
• “TUNE” indicator flashes for 1 to 2 sec. for the first tun-
ing on a channel.
u
Push and hold [PTT] on the microphone, and speak
into the microphone at a normal voice level.
• The RF meter shows the output power according to your
voice level, when RF power meter is selected.
i
Release [PTT] to return to receive.
[
RIT
]
[
AF
]
[RF/SQL]
Microphone
connector
The following modes are available in the IC-78:
SSB (LSB/USB), CW, CW REV (CW reverse), RTTY,
RTTY REV (RTTY reverse) and AM.
➥
Push [MODE] to select desired operation mode.
➥
Push [MODE] for 1 sec. to change between USB
and LSB, CW and CW reverse or RTTY and RTTY
reverse. (SSB, CW and RTTY mode only)
• The selected mode is indicated in the function display.
Note: The selected mode can be used for temporary
operation only.
OPERATING MODE SELECTION
Push
momentarily
Push
for 1 sec.
USB
LSB
CW
CW
RTTY
RTTY
AM
MODE
MODE