Behringer MX8000 eurodesk faulty

[rdtguitar]

The power supply provides +18, -18, +48 ref the analogue ground and +5 and +12 ref the digital ground.

You may have a failure in the power supply. You may have a failure in the desk pulling a power rail down. You may have both if a desk fault has caused the PSU to fail.

Check and fix the PSU first. Then if you have a split rail bench power supply power the +/- rails of the desk with that to see if you have a shorted rail.

This thread has excellent advice on fixing common faults in both the power supply and the desk in earlier posts.

Good luck.

Opened Mixer and removed PWR connector to each of 3 inner CH Boards. Put them back one by one
and my +18v is back. Someone else I know had this board & told me to check ribbon connectors.
Could that really be my problem , a connection went open? Ever see anything like that?

BTW Checked PS and voltages are mostly low +14v/-15.8v (and continues to drop under 8ohm load- load is 25 years old 100W resistor) +44.8v (don't use this Phantom v) +3v +11.2v-- def not in MIL_SPEC but OK for Behringer?

Any thoughts . Afraid to close it back up!

[g1]

Check for bad solder at the ribbon connectors.

[Enzo]

The MX8000 has a separate rack mount power supply. I'd look in ther for cracked solder on the regulator ICs and in general.