Agc; Noise Blanker - Yaesu FT-857D Operating Manual

AGC ( A
The receiver recovery time constant of the AGC system may be modified to match your
operating needs.
1. Press the [ FUNC ] key momentarily, then rotate the SELECT knob, as needed, until
Multi Function Row "l" [ NB, AGC, AUTO ] appears on the display.
2. Press the [ C ] key to toggle the AGC recovery time constant among the following selec-
tions:
AUTO ð FAST ð SLOW ð AUTO > .....
where "AUTO" represents "FAST" on CW and DIG (AFSK), and "SLOW" on the voice
modes.
If you disable the AGC by pressing the [ B ]( AGC ) key (to make the parentheses
disappear), the S-meter (which monitors AGC voltage) will cease to function.
Depending on the setting of the RF Gain control, incoming signals will probably be dis-
torted if the AGC is turned off.
The IF Noise Blanker may be useful in reducing or eliminating some types of impulse noise,
especially noise generated by automotive ignition systems.
1. Press the [ FUNC ] key momentarily, then rotate the SELECT knob, as needed, until
Multi Function Row "l" [ NB, AGC, OFF ] appears on the display.
2. Press the [ A ]( NB ) key to activate the Noise Blanker. The "u" icon will appear at the left
side of the "NB" selection, indicating that the Noise Blanker is now on.
3. To adjust the blanking level, press and hold in the [ A ]( NB ) key for one second. This
instantly activates Menu Mode No-063 [ NB LEVEL ] , which allows adjustment of Noise
Blanking Level. Rotate the DIAL knob to set a higher or lower blanking level (on a scale
of 0 to 100). When done, press and hold in the [ FUNC ] key for one second to save the
new setting and return to normal operation.
4. Press the [ A ]( NB ) key again to turn the Noise Blanker off.
During very crowded band conditions, you may wish to turn the Noise Blanker
off, as its use will degrade the strong-signal-handling capability of the receiver
somewhat.
FT-857 Operating Manual
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OISE LANKER
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