ICOM 301500 Manuale Utente

30

3

BASIC OPERATION

N RF gain and Squelch

N Meter function

The  [RF/SQL]  control adjusts the RF gain and 
squelch threshold level. The squelch stops noise out-
put from the speaker (closed position) when no sig-
nal is received.

•  The 12 o’clock position is recommended for any setting 

of the [RF/SQL] control.

•  The [RF/SQL] control can be set as the RF gain control 

only (squelch is fixed open) or squelch control (RF gain is 
fixed at maximum) in the set mode (p. 75). See the table 
as below.

SSB, CW

RTTY

RF GAIN

SQL

RF GAIN + SQL

AM

SQL

SQL

RF GAIN + SQL

M Adjusting RF gain (Receive sensitivity)
Normally, the [RF/SQL] control is set to the 12 o’clock 
position.
Rotate the [RF/SQL] control to the 11 o’clock posi-
tion for maximum sensitivity.

•  Rotate the [RF/SQL] control clockwise to increase, coun-

terclockwise to decrease the receiver sensitivity.

• The S-meter indicates receive sensitivity.

M Adjusting squelch (Removing non-signal noise)
Rotate the [RF/SQL] control clockwise until the noise 
just disappears when no signal is being received.

• “

” disappears.

•  Rotate the [RF/SQL] control past the threshold point in-

vokes the S-meter squelch— this allows you to set the 
minimum signal level needed to open the squelch.

•  A segment appears in the S-meter to indicate the S-me-

ter squelch level.

Minimum RF gain

Adjustable range

RF gain adjustable
range

Maximum RF gain

Maximum RF gain

Squelch is open.

S-meter squelch

S-meter squelch
threshold

Squelch is open.

S-meter squelch

S-meter squelch
threshold

• When functioning as RF GAIN/SQL control

• When functioning as RF GAIN control

• When functioning as SQL control

Lowest Threshold

Highest Threshold

The transceiver has 3 transmit meter functions for 
your convenience. Select the desired meter from RF 
power (Po), ALC and SWR.

±

 for 1 sec. to toggle between 

RF power (Po), SWR and ALC.

 

• The display indication changes as the following table.

Po

Indicates the relative RF output power. 

SWR

Indicates the SWR on the transmission line.

ALC

Indicates the ALC level. When the meter 
movement shows the input signal level 
exceeds the allowable level, the ALC lim-
its the RF power. In such cases, reduce 
the MIC gain setting (see p. 31) in the 
quick set mode.