Mark's Scanner Easier to Read Scanner Manuals Are Your Friend
The text below is from Mark's Scanners Easier to Read Manuals under
Creating (Programming) Objects
CONV (Conventional) Object Menu
at this link:
Easier to Read Pro-651/652/106/197 - WS1040/1065 - PSR 500/600 Digital Scanner Manual
Modulation: Selects the receive mode for the object. Auto will work fine unless you want to force a mode. Default is Auto.
Press ◄ or ► to select:
Auto - automatically detects the receive mode.
AM - forces AM mode.
FM - forces FM mode.
NFM - forces NFM mode.
AudioBoost: When set to 'On', sets a 6 dB boost to audio levels when the object is active. Default is Off.
Press ◄ or ► to select On or Off.
I would force the NFM mode first for each object and if that is not loud enough set the Audio Boost to On for each object.