I recently bought a replacement amp board off of KMAC Parts, i adjusted the signal pot and tacho pot to get the correct following error then adjusted the balance pot till that was correct, i also wound the gain pot out fully clockwise, but the first time i used it, it lost its position by about .2" i then sent it home and it didnt go to its cold start position even though it said it was at zero, so i turned it off, and done the cold start and it went back to its correct position. I also noticed when i turn it off and on it jumps a bit on this axis as well. Has any one any ideas on this matter as ive alredy destroyed one jig from it losing its position and i dont want it to happen again.
It sounds like you did not adjust the amplifier as it should have been done. Since I don't know if you have AC or DC servos nor do I know if you have Glentek or AMC amplifiers, I can't tell you the correct procrdure. Check in the Maintenance Manual under the "Axis Drive Sysytems". Look for the Servo Loop Gain procedure.
I doubt that the amplifier adjustment cause the loss of position. There must be something else going on as well.