MCE VVMC 1000 Controller, 1995/96 vintage - "Quad Pulser Relation" Errors (QPR's) LS-Quad Distance Feedback tape reader. Replaced GIO, DDP, SB1 sensor, LS-quad board, painted tape black, replaced twisted pair traveler, confirmed shielding and grounding,...scope shows good signal, quadrature good (there is a 15 volt, 12-15 hz sawtooth waveform riding on top of the 60 vdc square wave "on" signal, cannot confirm if it is acceptable or not) Intermittent problem - can be good for days or occur multiple times in a short period. Any ideas ???

-- WL (safetyedge@aol.com), November 11, 2002