A printed circuit board (PCB) is for mechanically support and electrically connect electronic components. It uses conductive tracks and other features.
double Side Copper prototype pcb
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Wave Sensor Ranging Detector
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PCBs can be single sided (one copper layer), double sided (two copper layers) or multi-layer.
Conductors on different layers are connected with plated-through holes called vias.
Advanced PCBs may contain components – capacitors, resistors or active devices – embedded in the substrate.
Where to buy?
Cheap prototype boards can be found on Aliexpress: