To reduce interference or noise caused by strong 
signals, you can reduce the scanner’s sensitivity 
There are two attenuator modes in your scanner. 
One is normal attenuator mode, in which you set 
the attenuator for each channel or each band/
group in the search and tune mode. The other is 
global mode in which you set the attenuator only 
once. This setting is applied all the time in every 
 to turn on or off the attenuator while the 
channel number is indicated or while the scanner 
is searching through bands/groups. When the 
ATT disappears. You cannot ATT
set the attenuator while the scanner is scanning 
 to set the attenuator to its 
global mode. A bar appears at the left of 
 to turn the attenuator on or off. 
 again to turn off the global 
attenuation mode. The bar disappears.
If you turn on the attenuator, the scanner might 
not receive weak signals.
turning the key tone on and off
Each time you press any of the scanner’s keys, the 
scanner sounds a tone. To turn the scanner’s key 
If you turn on the attenuator, the scanner might 
not receive weak signals.