Rana, Jenne, Koji
Last night we checked MZ. The apparent thing we found was the gain slider does not work.
The slider actually changes the voltage at the cross connection of 1Y2 (31 pin4?), the gain does not change.
The error spectrum didn't change at all even when the slider was moved.
Rana poked the flat cable at the bottom of 1Y2, we had no imporvement.
We coudn't find the VME extender board, so we just replaced AD602 (=VGA) and LT1125 (=Buffer for the ctrl voltage).
Even after the replacement, the gain slider is not working yet.
Today, I will put a lead or probe to the board to see whether the slider changes the voltage on the board or not.
Somehow the gain is sitting at a intermediate place that is not to low not to high. So I still don't know the gain slider
is the cause of the MZ instability or not. |