Few years ago, when I made this remote control for my shop dust collector I did not think it was worth publishing. Recently I noticed a forum discussion asking for details so here it is.
No experience in electronics, just basic understanding of electricity and current flow, and some basic tools are needed in order to build this unit, which essentially is a collection of off-the-shelf building blocks we integrate into a working system.
We start with a remote and a receiver used for garage door opening and similar applications. Usually they come as a set but you can also buy them separately and teach the receiver to recognize a specific remote. The other two parts in the box are a power supply needed to provide current to the receiver. You can use an open frame power supply mounted inside the box as I did or a wall-socket power supply that will keep the box smaller and less packed. If you have electronics junk laying around, most probably you can find a power supply you can use from an old printer and many other devices, just make sure it provide the same voltage needed by the receiver. The relay, which switches the dust collector on and off, is also not a specific component and can have many implementations. In my case I used a Solid State Relay (SSR), which acts like a mechanical relay but has no moving parts. It is more reliable but for this application, any relay that can hold the power needed by the dust collector will do. Make sure to check the power (Volts X Amps) your DC drawn and match the relay to support it as minimum.
Finally, you need to wire the power supply to the receiver, pair between the receiver and the remote control (usually done by removing the “teach” jumper from the receiver’s PCB, clicking on the remote button and replacing the jumper), and wire the relay from the main supply to the dust collector using standard plug and socket.