41
FT-857 Operating Manual
R
ECEIVER
A
CCESSORIES
AGC
(
A
UTOMATIC
G
AIN
C
ONTROL
)
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.
N
OISE
B
LANKER
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.
