The Tiantianyong tv-139f outwardly looks very similar to the various Chunghop RM-139 models (e.g. RM-139E). However, Dynex is not listed in the codes (to date I've not come across Dynex in any of the various Chunghop code sets) so it looks as though a code search will be your only option. If that doesn't work it's unlikely there is a code.