Summary

Identical to the Sony PVM-20M2MDU.

Literature

• Service Manual
• Owner's Manual
• Sales Brochure

Common Repairs

• Power Supply Failure: Try testing with known good PSU if available. If not available test PSU outputs with load to see if voltage is within spec printed below connector. Regulators commonly fail. Cap failure less likely but still possible.

• 3 RGB lines at top of screen: Check if underscanning (either with toggle switch or due to V-Height). If not underscanning then there is a deflection capacitor failure. Replace C-572 and C-584 on A Board. There is an old recommendation to adjust the V-BLNK (V-Blanking) value in the service menu to 'push' the lines up off of the screen but this is not recommended and only a temporary fix at best. It can further accelerate the death of the aforementioned capcitors and cause damage to other components. More information here: RetroTech on YouTube

• Blurry rainbow circles when shutting off monitor: Spot killer isn't working. No known fix at this time, there is no risk in continuing to use the monitor as normal.

Notes

OSD Service Menu can be accessed by pressing Menu, then Menu + Degauss. New settings won't be saved unless you commit them to memory by pressing Degauss twice. If you want to recall a setting from memory, press Blue Only twice.

The firmware for MDU monitors is different from regular M monitors, in order to support the different menu options (RGB Input Config for ex) and front panel buttons. The regular M2U board and fiirmware ARE compatible with M2U boards but they are not 1:1 interchangible in terms of function support. M2 boards do not support overscan mode or RS232 control. If you use an M2 board with an MDU front panel, it will work with the following caveats: The A and B input selection will be inverted, and "RGB A" will toggle RGB signal mode while "RGB B" will toggle Component/YPbPr mode, and "Split" will be Ext Sync toggle on/off.

If you remove the DIP 64 CPU from an MDU board and install to an M2 board combined with an MDU front panel, all MDU controls will work correctly except overscan, which will toggle HV delay. The MDU main board utilizes the HV delay signal line for the overscan toggle, which is why this button performs a mismatched function. I would assume overscan also requires additional deflection circuit components that are not included on a regular M2 board, but that is just personal speculation.