Sony Magnescale help?

[brucepts]

I'm installing a Sony magnescale DRO on my milling machine, problem is the Y axis is always showing approx .002 off. I've gone through the calibration for the amplifier head and still get the same reading. If I move the table .010 I get .0075 seems to be somewhat linear across the length of the scale. Anyone out there offer any advice for the Diy'er? I'm not able to send this unit out to have it professionally calibrated and I sure don't need .0001 accuracy. The X axis works correctly but thats a newer style scale. Thanks in advance.

[JimGlass]

Hi Bruce;

I think I have one of those Sony units. I have not had trouble with mine so I'm guessing at best. Mine has a lighted diode on the read head that gets brighter as the head aligns better with the scale, so check that. Check the scale for dirt.

Hmmm. Seems like mine had a blank or blinking screen if it wasn't working right.

Jim

[Doug_C]

Hey Bruce,

Don't know if you have tried swapping the scale inputs to verify if it is the scale or the input that is causing the problem.

The resolution of the scale vs the input scaler parameter may be a factor. I can't tell you if that is done via the display or internally with DIP switches. If it is always off by only .002, no matter how far you move it. That symptom could manifest itself in either the head or the scale, as it sounds like signal switching takes a few pulses to get it to recognise a threshold change in state to begin counting. Could be a bad connection with high resistance or another component failing to pass the signal.

You could try flushing the scale out with contact cleaner. Check that it is safe on a few plastic parts before trying this. These should not be glass scale encoders. A specific distance between the read head and the magnetic scale surface may be the culprit. A chip in the way could really screw this up.

Last thought would be to contact Sony support through their website.

Sinusoidal scales are harder to troubleshoot than square wave TTL signal scales.

DC

[brucepts]

Thanks for the insight! Upon further checking I think I have determined that the scale simply is not for use on the newer display I am trying to use it with. I setup an older single axis display and hooked the scale to that, moved it .010 on the indicator and it reads .010. So this leads me to beleive that the Display (LH-10) does not translate a SR style scale. Oh well my plan for this 'work around' will be to use the single axis display with the old scale on the Y axis and the new two axis display with the new scale on the X axis till I find a newer scale that will work. Thanks again for the help!! PS Sony is not willing to help alot with older setups.