Timothy, I have been using the Fire HD 8 for quite some time, and have had no WiFi dropouts or other WiFi issues. I am usually connected for over an hour and worked fine.
Probably make sure both mount and tablet are fully powered/charged.
Vero Beach, FL
Scopes: ES ED80CF, ES AR102, Meade ETX 90 EC (Deforked)
Mounts: ES iExos 100-PMC Eight, ExploreStars IPAD & Fire HD8, Explore FirstLight EXOS Nano
Nikon D600, D5500