My Typhoon H starts its motors but refuses to take off - that is, refuses to throttle up. It complains of no GPS lock. I returned to using my Q500 while reading forum threads. I notice mention of a GPS battery to maintain its data table. In as much as I have a Chroma that has never been flown, a Q500 that had to sit for a longtime acquiring GPS data when I returned it to service, and a Typhoon H with a GPS complaint, it seemed prudent to ask how easy it is to pop the tops on all three drones and replace their GPS batteries?