Which stands for Pulse Code Modulation. That part is essential. Its the part that stops any interference, or loss of signal from destroying your powerchair or house... Or from running away into traffic for e.g. and causing an accident!  This PCM bit matters! Don't consider trying this unless you think that part through first!

PCM allows you to program the receiver to STOP the powerchair as soon as any signal loss or interference happens. Even if someone is on your "frequency" it just stops.

How exactly you connect it to a powerchair I will come to later.

Why do I need it? Well today for e.g. I got into my van and drove another powerchair in behind me to transfer to the workshop at the local college for some modifications. There's no way I can do that while already seated in another powerchair!  I used it first thing too to bring my powerchair to my bed from the other side of the room.

I use it maybe once a week now for ten years or so. I work on powerchairs and clean them by sitting in one and driving the other remotely to the garage, workshop, into the house, etc.

I am pretty good at it now, I can drive two at once accurately through doors and along the pavements and around the house. Its actually very easy and smooth.  Thats the one I am sat in and the empty chair too!

The square expensive blue and black part is a Penny & Giles interface for connecting puff and sip controls and other switches and stuff to a power wheelchair. It also has an analogue input that is pretty useful for my purposes. It has a 3 volt "voltage swing" input. Actually it has two.  One for forwards and backwards, and one for left and right.

So that's easy! It has, in addition to the plus and minus 3v inputs a 12 volt supply! And obviously a zero volts too. You just need to make your two radio control channels channels "swing" above and below a reference point by 1.5v each way.