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4
1
PANEL DESCRIPTION
1
➥
Activates or selects fast, middle or slow
AGC time constant when pushed. (p. 59)
• “FAST” is only available for FM mode.
➥
Enters the AGC set mode when pushed
for 1 sec. (p. 59)
AGC time constant can be set between 0.1 to
8.0 sec.
(depends on mode)
, or turned OFF. While
“OFF” is selected, the S-meter does not function.
✔
What is the AGC?
The AGC function controls receiver gain to produce a con-
stant audio output level, even when the received signal
strength is varied by fading, etc. Select “FAST” for tuning and
select “MID” or “SLOW” depending on the receiving condi-
tion.
➥
Turns the VOX function ON and OFF
when pushed in a phone mode (SSB, AM
or FM mode). (p. 66)
➥
Enters the VOX set mode when pushed
for 1 sec. in a phone mode. (p. 66)
✔
What is the VOX function?
The VOX function (voice operated transmission) starts trans-
mission without pushing the transmit switch or PTT switch
when you speak into the microphone; then, automatically re-
turns to receive when you stop speaking.
➥
Selects semi break-in, full break-in oper-
ation, or turns the break-in operation
OFF when pushed in CW mode. (p. 67)
✔
What is the break-in function?
The break-in function switches transmit and receive with CW
keying. Full break-in function (QSK) can monitor the receive
signal during keying.
➥
Turns the RTTY filter ON and OFF in
RTTY mode. (p. 45)
• When the RTTY filter is turned ON,
[TWIN
PBT]
functions as the IF shift control.
➥
Enters the RTTY filter set mode when
pushed for 1 sec. in RTTY mode. (p. 45)
✔
What is the IF shift?
The IF shift function electronically changes the center of the
IF (Intermediate Frequency) passband frequency to reject in-
terference. Only the inner control of
[TWIN PBT]
can be
used for the IF shift control.
➥
Turns the speech compressor ON and
OFF in SSB mode. (p. 68)
➥
Switches the narrow, middle or wide
transmit
fi
lter when pushed for 1 sec.
✔
What is the speech compressor?
The speech compressor compresses the transmitter audio
input to increase the average audio output level. Therefore,
talk power is increased. This function is effective for long dis-
tance communication or when propagation conditions are
poor.
➥
Turns the
1
⁄
4
function ON and OFF in
SSB data, CW and RTTY modes. (p. 27)
•
1
⁄
4
function sets dial rotation to
1
⁄
4
of normal
for
fi
ne tuning.
➥
Switches the tone encoder, tone squelch
function and no tone operation when
pushed in FM mode. (pgs. 52, 53)
➥
Enters the tone set mode when pushed
for 1 sec. in FM mode. (pgs. 52, 53)
!7
NOISE REDUCTION LEVEL CONTROL [NR]
(outer control; p. 65)
Adjusts the noise reduction level when the noise re-
duction is in use. Set for maximum readability.
• To activate this control, turn the noise reduction ON in
advance (
!8
).
!8
NOISE REDUCTION SWITCH [NR]
(p. 65)
Push to switch the noise reduction ON and OFF.
• The
[NR]
indicator in this switch lights green when the
function is activated.
!9
NOISE BLANKER SWITCH [NB]
(p. 64)
➥
Switches the noise blanker ON and OFF when
pushed. The noise blanker reduces pulse-type
noise such as that generated by automobile igni-
tion systems. This function cannot be used for
FM mode, or non-pulse-type noise.
• The
[NB]
indicator in this switch lights green when the
function is activated.
➥
Enters the noise blanker level set mode when
pushed for 1 sec.
@0
BALANCE CONTROL [BAL]
(inner control; p. 63)
Adjusts the audio output balance between main and
sub readout frequencies while in dualwatch.
BAL
NR
Increases main
readout gain
Increases sub
readout gain
Noise blanker OFF
Noise blanker ON
NB
NB
Noise reduction OFF
Noise reduction ON
NR
NR
BAL
NR
Decreases
OFF
Increases
TONE
TONE
OFF
OFF
1/4
1/4
OFF
OFF
COMP
COMP
OFF
OFF
WIDE
WIDE
RTTY
RTTY
FIL
FIL
OFF
OFF
BK-IN
BK-IN
OFF
OFF
VOX
VOX
OFF
OFF
AGC
AGC
MID
MID