LCSO uses an 8 frequency EDACS trunked system. It is a bit more complicated than entering a single frequency. You need to program a trunking scanner (Uniden, RadioShack or GRE) with all 8 freqs in the proper order in the proper way.
We would need to know what model scanner you have and from that we can tell you if it is capable of actually following the system or not.
If you want to attend the next CARMA Meeting (Saturday, March 3 in Willowbrook) one of us will program your scanner for you as long as it is capable of the type of system. Otherwise send me a PM (Private Message) and I will see if we have someone in your area that can meet up with you and help program the scanner. A bunch of us live here in Lake County.
Unless the scanner is a "trunking scanner" you will have a awful time keeping a conversation because after each transmission there are four "beeps" hanging up the scanner, thats the type of system they use called "EDACS....You can find the system (Lake Co) here on this web site in the "Database" for ILL....
Sorry, the BC72XLT does not follow EDACS systems or the 800 MHz. freqs they use. You will need a new scanner to listen to Lake County.
You can use the GRE PSR310 or the Uniden BC346XT for under $250. If you want to step up to digital (to listen to the State Police or McHenry County) then you can get a PSR600/Pro106 or BCD396XT for $450 to $500. Any of these radios will work on the EDACS system and the digital scanners will work for the State Police, McHenry County and other localities that use StarCom21.