In digital mode, you must define "Talkgroups" in the Contact list. Each channel must be linked to a specific talkgroup for the radio to transmit to the correct audience.
Before you buy a used MOTOTRBO radio off eBay, ask the seller: "Has the 90-day programming grace period expired?" If they don't know, assume you will need to spend $175-$300 on a CPS 2.0 entitlement to program it. Motorola Mototrbo Cps 2.0 Programming Software