In DC voltage applications, the RC snubber network is typically wired across the relay contacts, whereas in standard AC ...

That means it has no gaps. You can use a switch in a circuit to create a gap in a circuit. This can be used to switch it on and off. When a switch is open (off), there is a gap in the circuit.

DIY WiFi-Controlled Drone Complete Circuit Diagram The complete circuit diagram for the DIY WiFi Controlled Drone is shown below. It can also be downloaded in PDF format from the link given at the end ...