Quote Originally Posted by Ioannis View Post
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So, I would suggest to take cables from all the minus (ground points) of the circuit parts and connect them to a single point where your (-) of the power supply is....

Ioannis
And, from right there, have a bobbin serially connected to GND, thus, all of your circuit will go to GND via that bobbin.

The value of the bobbin is best found by experimenting.


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