Automatic Gain Control (Agc); If Gain Control; Squelch Control - AOR AR7030 Operating Manual

RF / IF menu - the LCD will show Gain above the
spin-wheel, but this is IF gain (see section 6-11) - the
RF gain setting is shown in the centre of the display
between up and down arrows. For example < RF+00 >
indicates the normal setting.
Pressing the buttons below the up or down arrows changes
the RF gain setting. The value displayed is actually the
maximum value that the receiver will use. Unless
specifically disabled (see section 9-4) the RF gain will be
reduced automatically when strong signals are received -
this maximises the AGC range of the receiver. Signal
strengths over S9+40dB will reduce RF gain, which will
be restored again if signal strength falls below S9+10dB.
There is a small delay in this automatic system to prevent
spurious switching during signal fades.
To restore an S-meter display, press the

6-10 Automatic Gain Control (AGC)

The RF / IF menu is used to select the AGC setting, which
may be different for each mode and VFO. The AR7030
features a newly designed AGC system with a special
release characteristics for very smooth audio especially
when monitoring SSB.
If the S-meter is not displayed, press the
return to the menu root. Press the
the RF / IF menu - the LCD will show AGC above the
button and the AGC setting (Fast, Med, Slow or Off) above
that. Pressing the
four settings.
The default settings for each mode are:-
AM Slow
Snc AM Slow
USB Medium
LSB Medium
CW Medium
Data Medium
NFM Fast (no other setting
Generally speaking Slow AGC will provide the best audio
quality when signal strength is steady. Under fluctuating
signal conditions a faster speed will keep track of the
changing signal level. When listening to SSB transmissions
a faster speed will increase the noise during pauses in
transmission, but will enable a weak signal to be heard
more quickly after a strong transmission or a burst of
interference. When tuning quickly, AGC is automatically
set to fast speed - it returns to the user setting when tuning
stops. AGC off can be used in conjunction with the
IF gain control for squeezing the very last ounce of
performance out of the receiver under difficult conditions.
button.
button to
button to choose
soft-key will cycle through the
recommended)
To restore an S-meter display, press the
The AGC speed control will remain available on the
button.

6-11 IF Gain control

The IF Gain control reduces the amplification in the
receiver's IF circuits and has the effect of reducing the
sensitivity of the receiver. Normally this job is performed
by the AGC system, and the control is left at maximum
gain (99%), but reducing the gain can be useful to limit
noise when listening to CW or SSB signals. The IF Gain
control must be used if the AGC is turned off.
The RF / IF menu is used to adjust the IF Gain setting,
which may be different for each mode and VFO. If the
S-meter is not displayed, press the
to the menu root. Press the
RF / IF menu - the LCD will show Gain above the spin-
wheel and the gain setting (3% to 99%) above that. Turning
the spin-wheel will alter the gain.
To restore an S-meter display, press the
IF Gain control will remain available on the spin-wheel .
Note: Because the IF Gain, S-meter and squelch systems
are inextricably linked, the signal strength indication will
increase as IF Gain is reduced. Squelch operation is
impaired unless the IF Gain control is set to its maximum
99%.

6-12 Squelch control

The AR7030 is equipped with an all mode squelch system
which may be used to eliminate unwanted background
noise when monitoring a normally inactive frequency (such
as 5.680MHz international search and rescue) or for scan
control when dual VFO or memory scan is selected. The
squelch is not normally used when listening to broadcast
transmissions because they are continuous. In this case
the squelch level is set to 0% (squelch off).
The squelch operation is controlled by signal strength and
can be used to mute the receiver's audio, control the scan
/ hold (for memory scanning and dual VFO operation) and
control the auxiliary relay (for switching a tape recorder).
Each of these functions can be enabled or disabled as
required (see also sections 7-3, 8-4 and 9-4).
Squelch level is adjusted with the spin-wheel, the function
being available from several menus when it is likely to be
needed (in NFM mode and when scanning memories).
General access to the squelch level is easiest through the
VFO menu. If the S-meter is not displayed, press the
button to return to the menu root. Press the
button and then the
menu - the LCD will show Sql above the spin-wheel,
AR7030 OPERATING MANUAL
button.
button to return
button to choose the
button.
soft-key to choose the VFO
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