Open Sentinel's Discovery Log viewer:
TOOLS > DISCOVERY LOG VIEWER
Click icon encircled in green (Import Discovery log)
Choose which Conventional or Trunked session you want to back up
You can choose which hits to back up (Hold down CTRL key and click each entry or Select All (CTRL+A) to select them all
You then have the option to right-click Copy to Clipboard & paste them to your text editor of choice.
I assume the logs are some where on the PC when I Import the Discovery Logs.
If you close out of the Discovery Viewer then choose
File > Save to save your Sentinel profile then by default the discovery log will be located at
C:\Users\[username]\Documents\Uniden\BCDx36HP\DiscoveryLog unless you specified a different output folder via
Tools > Options