Earthing Norms DAC...

[rog8811]

Thanks for puting in the effort to do the drawing, I will prototype it at the weekend and let you know how I get on.

Regards rog8811

[rog8811]

I think, again, I am having earthing issues........ I quickly breadboarded an opto isolator driving an LED to test for blanking output, with popelscan running I had a dim but flashing LED. The moment I turned on the the power to the scanner the LED stayed resolutely brightly on, so not blanking I scoped the output from the DAC and sure enough the signal is there, at the outputs, with just the computer running and disappears as soon as the scanner is running.


I also looked at the blanking arrangement on the DX red/green driver (3 wires [red side of circuit/ground/green side of the circuit]) and discovered that to blank the LD's you need to short the red and/or green to ground to turn off the LD's. I cannot at the moment see how I need to configure the DAC blanking output to do that.

Any ideas on what to try with any of the above please?

Regards rog8811