There are a few things to check.
First, did you program the frequencies for trunk operation? If it's a Motorola system the letter "M" will appear before the channel number. If it's EDACS, the letter "E" will appear. It's a common error, especially if you are programming manually to enter the frequencies as conventional when you meant to enter them as trunked. It's not a very intuitive system.
Are you hearing the control channel? Take the scanner out of Trunk mode and put the scanner into Hold/Manual. Step through the channels one at a time. On one of the channels, you should hear a buzzing sound. That indicates the control channel. If you don't hear that, recheck the frequencies. You either missed one, have one programmed in correctly, or maybe are too far from the system to hear it. I doubt that last is true as you are hearing the voice channels.
As seamusg wrote, check to make sure you have the correct type of system programmed.
I'd recommend tossing the free software since it's worth what you pay for it. If you plan to do a lot of programming and reprogramming of the scanner, you'll be doing yourself a favor to get ARC250 by Butel.
I hope this helps.
Gary
