A cure for erratic/intermitten R.I.T. operation on older OMNI-VI. Add a chassis ground to C1-C4 on the Display Driver Bd. An easy point to attach a ground lug is the right hand mounting screw for the Display Bd. C1-C4 are the two electrolytic caps on the top edge of the Display Bd as you look down from the top of the rig. 73 KF4HHO