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PANEL DESCRIPTION
#0
MULTI-FUNCTION KEYS
Push to select the functions indicated in the display
to the right of these keys.
• Functions vary, depending on the operating mode.
➥
Push to select the ANT1, ANT2, ANT3 or
ANT4 antenna connector.
➥
Hold down for 1 second to display the
• When the receive antenna is activated, the
antenna that is connected to [ANT4] is used
only for receive.
When a transverter is used, this [ANT]
does not function and “TRV” appears.
➥
Push to select the RF power
(P
o
)
, SWR,
ALC, COMP, V
d
or I
d
metering while
transmitting.
➥
Hold down for 1 second to turn the Digital
multi-function meter ON or OFF.
➥
Push to select one of two receive RF
• “P.AMP1” activates a 10 dB preamp.
• “P.AMP2” activates a 16 dB high-gain pre
-
amp.
✔
What is a preamp?
A preamp amplifies received signals in the front end
circuit to improve S/N ratio and sensitivity. Select
“P.AMP1” or “P.AMP2” when receiving weak signals.
➥
Push to select the 6 dB, 12 dB or 18 dB
attenuator.
➥
Hold down for 1 second to select the 3
dB, 6 dB, 9 dB, 12 dB, 18 dB, or 21 dB
attenuator.
✔
What is an attenuator?
An attenuator prevents a desired signal from distorting
when very strong signals are near the desired frequen-
cy, or when very strong electric fields, such as from a
broadcasting station, are near your location.
➥
Push to activate and then select the
“FAST,” “MID,” or “SLOW” AGC time con-
stant. (p. 7-4)
• In the FM mode, only “FAST” is selectable.
➥
Hold down for 1 second to enter the AGC
set mode.
The AGC time constant can be set be-
tween 0.1 to 8.0 second
(depending on the
mode)
, or turned OFF. When AGC is
“OFF,” the S-meter does not function.
✔
What is AGC?
The AGC controls receiver gain to produce a constant
audio output level, even when the received signal
strength varies dramatically. Select “FAST” for tuning
and then select “MID” or “SLOW” depending on the re-
ceiving condition.
➥
Turns the speech compressor ON or
➥
Selects the narrow, middle or wide com-
pression when held down for 1 second.
✔
What is a speech compressor?
A speech compressor compresses the transmitter au-
dio input to increase the average audio output level,
and therefore increase the talk power. This function
is effective for long-distance communication, or when
propagation conditions are poor.
➥
Push to turn the
1
⁄
4
-speed tuning func-
tion ON or OFF in the SSB data, CW,
RTTY and PSK modes.
•
1
⁄
4
function sets the dial rotation to
1
⁄
4
of the
normal speed for fine tuning.
➥
In the FM mode, push to toggle between
the tone encoder, tone squelch function
and no-tone operation.
➥
In the FM mode, hold down for 1 second
to enter the Tone set mode.
➥
Push to turn the Voice squelch control