(Portland, OR)  --  Sentencing is scheduled for August for a man convicted of detonating an explosive device during a traffic stop in Beaverton.  A jury convicted 27-year-old Jason Schaefer of two counts of assaulting a federal officer and other charges following a six-day trial.  Court records say Schaefer was under probation for a separate conviction in October of 2017 when he detonated an improvised explosive device inside his vehicle after an officer approached his window.  He's facing a possible sentence of life in prison.