They are designed to have near-to-perfect ratios. However some parts like copper wires (pic 1)and basic electronic components (pic 2) are a little backed up but it is a price for the elegance of design.
I tried to use as few input materials as possible. Ones that are made not out of basic resources are - Solder Plates, Carbon, Silicon Plates, Plastic.
Basic Electronics - Basic Circuits included
Electronics Circuits
