Starting at your Map screen on you Astro 320, press the Menu button and select Setup Dogs.
Select “Dog Track Length on Map” and select how long you would like tracks from your dc50 collar (Or DC40, and DC30) to stay on the screen before they disappear, you can also select off which will keep tracks on your screen until you decide to start a new hunt.
*if you haven’t cleared out your track log on you 320 handheld you can cycle through your current track setting, to all of your tracks, to none of them appearing on your map screen. This can be accomplished by pressing the map button while your are on your map screen. For example: if you have your track length set to ten minutes but you want to view tracks prior to ten minutes ago press the map key, this will bring up tracks prior to ten minutes up onto your screen, press the map button a second time it will take away all tracks on your map screen, press map a third time and the track will revert back to your ten minute setting.