On Sun, 6 Mar 2022, Mark Kimball wrote:
If you can at all afford it, stay away from remote-reading igaging DROs that have aluminum scales. The scale is part of the sensor circuit and has a sliding ground
contact made to it inside the sensor box. Aluminum develops an oxide coating, making that contact resistive -- and when it does, the scale turns into a magnificent
antenna for picking up electrical noise. I think that's part of the reason that messing around with the DROs could temporarily fix the problem, but it always came back.
I have 3 igaging DROs with aluminum scales, and all 3 of them now are hardwired to the sensor's internal ground -- holes drilled in the end and a screw + spade connector
attached. For me, this was the "final solution" to my EMI problem.
As a result of my experience, when I later bought two igaging DROs to put on my lathe I chose to go with stainless steel scales. Even for them I still had to solder an
additional 1 uF capacitor across Vcc and Ground inside the sensor box.
Mark _._,_._,_
Thanks
Good to know before I buy
