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Sentinel Programming

Uniden SDS100 Sentinel Programming Guide (2025)

Sentinel is the easiest way to keep your SDS100 updated and build clean Favorites Lists. This guide focuses on the exact workflow that prevents “Nothing to Scan” and makes scanning predictable.

Key takeaways (fast answers):
  • Update weekly: Update the database in Sentinel regularly—talkgroups and sites change.
  • Build Favorites Lists: Use Favorites for control; rely on ZIP scanning only as a quick start.
  • Most common failure: “Nothing to Scan” is usually Service Types, Quick Keys, or Location Control.
  • Always safe eject: After writing to the scanner/SD, safely eject before unplugging.
Last updated: December 12, 2025
Cite this page: Boy and a Scanner. “Uniden SDS100 Sentinel Programming Guide (2025).” https://boyandascanner.com/sds100-sentinel-programming.html (Updated 2025-12-12)
Primary sources & references: my.uniden.com · Uniden

What Sentinel Does (and Why It’s Worth It)

Sentinel is Windows-first. If you’re not on Windows, you can still manage the microSD via other workflows, but Sentinel is the simplest path for most users.

Step-by-Step: The Standard Sentinel Workflow

  1. Install Sentinel (from Uniden) and launch it.
  2. Update the database: In Sentinel, run the database update so your agency/site/talkgroup data is current.
  3. Connect the SDS100 via USB and select Mass Storage mode on the scanner.
  4. Read from scanner (optional but recommended if you’ve made changes on the radio): pull current settings and lists into Sentinel.
  5. Create a Favorites List and add your system(s) and the site(s) you can actually receive.
  6. Set Service Types appropriately (e.g., Law Dispatch, Fire Dispatch, EMS Dispatch).
  7. Assign Quick Keys so you can turn lists/systems on and off quickly.
  8. Write to scanner: Send Favorites Lists and settings to the scanner/SD card.
  9. Safely eject the scanner/SD from Windows, unplug USB, and start scanning.
Tip: If your Favorites List scans in Sentinel’s mind but the radio says Nothing to Scan, jump to the troubleshooting section below.

Favorites Lists: The 3 Settings That Matter Most

For troubleshooting, temporarily disable Location Control for a list and enable the common Dispatch Service Types to confirm you can receive traffic.

Backup (Highly Recommended)

Before you experiment, create a backup of your configuration.

If something breaks, restoring from backup is faster than re-building Favorites Lists from scratch.

Troubleshooting: “Nothing to Scan” (Fast Fixes)

If you’re also dealing with garbled P25 audio, see the Simulcast Fix Guide.

Frequently Asked Questions

What is Uniden Sentinel used for on the SDS100?

Uniden Sentinel is the official PC software used to update the SDS100 database and firmware and to build, edit, and write Favorites Lists to the scanner (systems, sites, departments, and channels).

Do I need a RadioReference subscription to use Sentinel?

Not for basic use. You can update the built-in database and program Favorites Lists in Sentinel without a subscription. Some advanced importing options may depend on RadioReference features in your workflow, but most beginners can start without one.

Why does my SDS100 say “Nothing to Scan” after programming?

Common causes are: the Favorites List is not enabled for scanning, Quick Keys are off, Service Types are disabled, Location Control/range is excluding items, or everything is avoided. Start by enabling the list and turning on the correct Service Types.

How do I write a Favorites List from Sentinel to the SDS100?

Connect the SDS100 via USB, select Mass Storage mode, then in Sentinel use the write-to-scanner function to send your Favorites Lists and settings. Safely eject the device when finished, then disconnect USB and scan.

Should I update the database or firmware first?

In practice, do both. A simple routine is: update Sentinel itself if prompted, update the database, then update firmware when available. After updates, write your Favorites Lists/settings to the scanner as needed.

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