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5
2
PANEL DESCRIPTION
✔
What is the AGC?
The AGC controls receiver gain to produce a constant 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 condition.
➥
Turns the VOX function ON and OFF
when pushed in non-CW modes. (p. 35)
➥
Enters the VOX set mode when pushed
for 2 sec. in non-CW modes. (p. 35)
✔
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.
✔
What is the break-in function?
The break-in function toggles transmit and receive with CW
keying. Full break-in (QSK) can monitor the receive signal
during keying.
➥
Turns the RTTY filter ON and OFF in
RTTY mode. (p. 28)
• When the RTTY filter is turned ON, [TWIN
PBT] functions as the IF shift control.
➥
Enters the RTTY filter set mode when
pushed for 2 sec. in RTTY mode. (p. 28)
✔
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. 37)
➥
Toggles the narrow, middle or wide trans-
mit filter when pushed for 2 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 CW
and RTTY modes. (p. 25)
•
1
⁄
4
function sets dial rotation to
1
⁄
4
of normal
for fine tuning.
➥
Toggles the tone encoder, tone squelch
function and no tone operation when
pushed in FM mode. (pgs. 46, 47)
➥
Enters the tone set mode when pushed
for 2 sec. in FM mode. (pgs. 46, 47)
TONE
TONE
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
@8
MAIN/SUB CHANGE SWITCH [CHANGE]
➥
Toggles the frequency and selected memory
channel between main and sub readouts when
pushed.
• Toggles between transmit frequency and receive fre-
quency when the split frequency function is ON. (p.
32)
➥
Equalizes the sub readout frequency to the main
readout frequency when pushed for 2 sec.
@9
MULTI-FUNCTION SWITCHES
Push to select the functions indicated in the LCD
display to the right of these switches.
• Functions vary depending on the operating condition.
➥
Toggles the antenna connector selection
between ANT1/R and ANT2/R when
pushed. (p. 45)
➥
Toggles the [RX ANT] (receive antenna)
ON and OFF when pushed for 2 sec.
When a transverter is in use, this [ANT]
does not function and ‘TRV’ appears.
➥
Selects RF power (Po), ALC, SWR or
COMP metering during transmit. (p. 36)
➥
Toggles the multi-function digital meter
ON and OFF when pushed for 2 sec.
➥
Selects one of 2 receive RF preamps or
bypasses them.
• “P. AMP1” activates 10 dB preamp for HF all
bands.
• “P. AMP2” activates 16 dB high-gain preamp
for 21 MHz band and above.
✔
What is the preamp?
The preamp amplifies received signals in the front end cir-
cuit to improve the S/N ratio and sensitivity. Select “P. AMP1”
or “P. AMP2” when receiving weak signals.
➥
Selects 6 dB, 12 dB or 18 dB attenuator,
or bypasses them.
✔
What is the attenuator?
The attenuator prevents a desired signal from distorting
when very strong signals are near the desired frequency, or
when very strong electric fields, such as from a broadcast-
ing station, are near your location.
➥
Activates or selects fast, middle or slow
AGC time constant when pushed.
• “FAST” is only available for FM mode.
➥
Enters the AGC set mode when pushed
for 2 sec.
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.
AGC
AGC
MID
MID
ATT
ATT
OFF
OFF
P.AMP
P.AMP
OFF
OFF
METER
METER
Po
Po
ANT
ANT
1