Did range check without engine running everything seemed fine smooth as could be. This is first time I did range check with engine running and only because I read the suggestion here in the forums. Glad I did I did pull the antenna up and it stopped when antenna was down you could back away and jitters start. Then walk bk up to plane and it quit, walk bk again and everything fine good throttle responce surfaces moving correctly and all. Let her set at idle for a few and she start jumping again. Throttle up and she clear up,