Mask electrical schematic diagram

Question 1

I have a schematic diagram that I would like to show as a process illustration, but would like to hide its details and protect from copying.

Any ideas how to graphically solve this task while keeping the picture looking nice?

It hides but looks terrible:

Question 2

One option would be to partially blur the image. Photoshop’s smart filters are ideal for that.

Open your image in Photoshop and turn it into an actual layer (rather than the background) by double-clicking the layer bar in the Layers palette;
Right-click the layer miniature and choose Convert to Smart Object;
Choose Filter > Gaussian Blur and choose a value that completely hides all detail in the picture;
Click on the filter’s layer mask and fill it with black to make it invisible everywhere;
Use a big, soft white brush on the filter’s layer mask to paint the filter visible in selected places.

Answer