The affidavit has this weird sentence saying "If the radar does not pass the test at the end of my shift I will prepare a supplemental report". This implies that the officer prepared the affidavit before the end of his shift and before testing the radar unit. You can try arguing that this makes it inadmissible - the affidavit states that the unit was tested at the end of the shift, but then it also says that it may have not been the end of the shift yet. I think there is a decent chance it will work.