Yaesu FT-991 User Manual

Page 45FT-991 OperaTing Manual
interference reJection
ATT
(
AttenuAtor
)
Whenthedesiredsignalisextremelystrongorthenoiselevelishighonalowfrequencyband,activatetheattenuatorto
reduce the incoming signal from the antenna.
1. Press the
F(M-LIST)
button,thentouch
[
ATT
]
on
theLCD.The“
ATT
”indicatorwillappearinthe
DSP display.
Advice:

 Theincomingsignallevelisreducedby12dB
(Signal voltage is reduced to 1/4 compared to OFF).
F(M-LIST) Button
Displays ATT
2. To restore full signal strength through the Attenuator
circuit, touch
[
ATT
]
 on theLCD to return theATT
display to the “
OFF
”position.
Advice:
Ifthenoiselevelishighorthereceivedsignalisextremelystrong,theincomingsignallevelcanbesuppressedwiththe
IPO/ATT settings.
IftheS-meteructuatesS-3ormoreinthenoiselevel,orthereceivedsignalisextremelystronganditcausesahighS-
meterindication(+20dBormore),activatetheattenuator.
SinceIPOdoesnotonlyattenuatetheincomingsignal,butalsoimprovesthecrossmodulationcharacteristic,trytoac-
tivatetheIPOrst.Ifthesignalisstillstrong,alsousetheATT.Inthisway,youcanattenuatetheincomingsignaland
noise effectively.

Yaesu FT-991 Specifications

General

Brand	Yaesu
Model	FT-991
Category	Transceiver
Language	English