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4.4.6 DESCRIPTION OF CONTROL WINDOWS 3 AND 4
STEP
This is the frequency increment used when selecting a frequency using the blue tuning
dial, or the PC keyboard's left and right arrows.
0.001kHz to 999.999kHz in 0.001kHz increments.
AF GAIN
Speaker and headphone volume slider.
ATTENUATOR and RF AMP
With the slider select either RF Amp: ON or OFF, Att:0, -10, -20dB, or AUTO. Refer to the
Main Control window for selection indication.
AGC
The AGC function controls receiver gain to produce a constant audio output level even
when the received signal strength is varied by fading, etc. Select either FAST, MID, SLOW
or MANUAL (adjust the AGC level with the slider).
SQL (noise squelch)
Use the slide to adjust the squelch threshold level. The squelch removes noise output from
the speaker (closed condition) when no signal is received.
VOICE SQL
This function opens the squelch only when receiving a modulated voice signal. Adjust
aggressiveness and delay (time until squelch opens) with the slide bars.
IF BAND
Use the slide bar to select one of the 10 available IF bandwidth filters. Refer to the Main
Control window for exact values.
IF SHIFT
The IF shift function changes the center of the IF (intermediate frequency) passband
frequency to reject interference.
+/-1200Hz
Refer to the main control window for exact values.
Not active in FM modes.
SPAN
Control the displayed spectrum bandwidth from 0.8MHz to 10MHz. The top left corner of
the spectrum indicates the exact span value.
CALC
The calculation function offers 2 alternative spectrum modes:
MAXIMUM: Each sweep is retained as data and built-up on screen.
AVERAGE: Signal averaging over the sampling cycle. A stable pattern is produced even if
the signal is fluctuating.
PEAKS
This function searches for the strongest signals in real time, in the displayed spectrum,
above a threshold level you can set with the slide bar.
10 peaks maximum. Select 0 to erase all peaks.
You can tune to the strongest signal in the spectrum with MAX, or only in one half of the
spectrum with LEFT or RIGHT.
WATER FALL SPEED
Control the waterfall speed by moving the slider.
WATER FALL COLOR
Control the waterfall color codes depending on the signal strength between -30 and -
110dB.
