I've got a two axis DRO on my mill with an old Mitutoyo GML-3705W
display unit. It's not been used for a bit over a year and when I
switched it on this evening nothing lit up on the display front panel.
I've taken it apart and the primary of the mains transformer is open
circuit between 0V and 100V (the lowest voltage tap). The taps between
100V and 240V all show a reasonable resistance.
The secondaries seem OK and aren't shorted. Nor are the reservoir caps
in the DC supplies shorted. The 500mA mains fuse is intact. Maybe the
transformer just gave up the ghost all on its own?
It seems unlikely Mitu will have a spare for this obsolete device, at
least not at a price I'll want to pay, although I will phone their place
in Andover next week. I'm expecting to have to get the original rewound,
or a have a custom one made, or just throw it in the bin and console
myself with the thought that DROs are cheating anyway.
In the meantime, I wonder if anyone has worked on one of these, or has a
circuit diagram, or knows what the transformer spec is, or has a working
spare they want to sell for not much? I know it's a long shot, but...