Roland mdx-650a question

is the MDX 540 the same board as well as the MDX 500? as you said the 650 is the same as the 500 just wondering as i have possible access to a 540 board.. any ideas?

No, the 540 is different to the 500/650.

The 540 does use the same horrible spindle motor, but the main board is different. I'm not sure what other similarities there are.
A guy contacted me with a MDX-40 spindle motor stator that uses the same hall effect sensors as ours use. His were all burned. Check yours.

mine is fine

okay I found a descrepancy on the motherboard....section for x servo the driver transistors all show 24V on the collectors on both left and right sides of the board, on the Y servo drive transistors on collectors on one side shows 24 but on the other side shows 13-14 volt not the same perhaps this is shwing me that maybe the drivers are bad!!?? I am going to look at the schematic again and see hw they are ocnifgured and if this is the case ot could possibly why it is failing before it gets to the z axis home etc.....

Yeah possibly.

The supply is from a 24v tap on the transformer. If something has failed short it could pull the voltage down. Transistors are cheap. Maybe buy a bunch and try substituting them.

do you have yours up and running? if so could you check to see if it is suppose to be 24v on all sides of the diodes or 14v one side and 24 on the other etc?

PM sent

PM- personal message? not sure is that a function on this forum? etc or another location ?

Pm here?

Sorry. I went to your profile messages>send email and gave you my email address to send some photos to.
Cheers.