Thanks, Tom. I'm working through the test procedures in the (rather
*large*) manual and am noting down the tests the machine doesn't pass.
I just assume the y-magnifier circuits are seperate (at *some* point)
between the polar and rectanguar trace display circuitry and that might
help to pin the problem area down somewhat. I'm very good at
troubleshooting (given a decent schematic) but have no experience with
this particular instrument.