I'm new to rc racing and in the process of building my car. I purchased a Spektrum DX2E Radio which comes with an SR200 receiver. The receiver only has 2 channels. Steering, throttle, and a spot for the bind plug. If I purchase a transponder where do I plug it in. Would it just go into the bnd slot. Or is this setup not suitable?

It can go into the Bind/Battery slot and have no effect on the other two channels since it's not connecting to the signal phase but only the positive and negative power leads.

Good to know. Thank you

What is a transponder and what is it for?

The term is a portmanteau for Transmitter-responder.
It is needed for Lap timing.

The link goes to the most common used System in RC.

http://www.mylaps.com/index.php/emea...es/B2C/rc/home

Cruise

It’s for lap counting when racing. Each RC has a transponder that signals the track’s lap counter and timing software program for each lap.

Older transponders were “house” transponders that the track supplied and the racers shared. Most now use a “personal” transponder (aka PT) that the racer buys and leaves in the RC, makes the race program run much smoother. Like the MyLaps Cruise linked to.