Welcome to RadioReference.
There are a large number of articles in the Wiki regarding your scanner model, including tips and techniques for programming.
Start with this page, and be sure to explore the links on the page. Some of the articles have links to YouTube videos that you might find helpful.
wiki.radioreference.com
There are "Easier to Read" online manuals for both your scanner model, as well as the Sentinel software.
It looks like many of the agencies in your area are on this system:
Metropolitan Emergency Services Agency (MESA) (Formerly IDPS) Trunking System Profile
www.radioreference.com
Be sure that you have the latest version of Sentinel installed on your PC. If you have not done so, you also need to install the serial driver needed for your PC. Links to Sentinel, and the serial driver, are both on this page:
info.uniden.com
Install Sentinel, and update the database. Then, connect your scanner to your PC, selecting 'Mass Storage Mode', and write the updated information to your scanner. Then, you can at least get started by entering your location (via zip code), and range, and also selecting the service types that you want to hear. When shipped, and/ or when Sentinel is first installed, only the Dispatch service types for Public Safety are enabled: Law Dispatch, Fore Dispatch, EMS Dispatch, & Multi-Dispatch. ALso enable the
Tac and
Talk service tyoes for those, i.e. Law Talk, Fire Tac, and so on.
For an explanation of how to use location and range to scan via the main database, see this page:
Uniden's HomePatrol-1 is the first digital TrunkTracker IV Communications Receiver that requires no user programming. Simply turn it on, enter your location, and you will immediately begin hearing communications in your area. This functionality is made possible by combining the rich radio system...
www.homepatrol.com
Remember that for systems that are in the database in Sentinel, you can append them from the database to a Favorites list. Using a Favorites list gives you more discretion on what you do, or do not, want to hear than just using location and range. But location will at least give you a starting point.