Red and a blue Jaguar D types racing

Well we've looked at the slot cars, and we've looked at the track. So now it's time to look at an easily overlooked, but vital component, the controller, or throttle. This is all you have to control your car, so making the right choice can make a big difference.

Analogue Hand Controllers

This is the only thing that connects you to your car and it makes a critical difference to your enjoyment of the hobby. If your controller is not properly matched to your cars you will not have optimal control and won’t be able to turn consistently fast lap times.

Unfortunately the controllers that come in most manufacturers' race sets are primarily designed to be as cheap to produce as possible. They are of poor quality and most don’t even have braking functions so are far from the ideal solution.

If you intend to use your cars properly then you will need to upgrade to aftermarket controllers.

Resistor controllers vs electronic

Resistor controllers are the ones supplied in sets and are basically 19th century technology. Electronic controllers are cutting edge, vastly superior but a lot more expensive.

On all controllers, when the trigger is in the "off" position the circuit to your car is broken and the car receives no power. As you pull back or release the trigger it varies the speed of your car by letting a greater or smaller portion of the available track power reach the motor. A resistor controller does this by converting a varying portion of the track power to heat. They get very warm in use and eventually the resistor will burn out. An electronic controller uses advanced circuitry to accomplish the same purpose but without the heat and will rarely break. When the trigger is pulled all the way back, the controller completes a direct circuit that gives the car all the available track power for maximum acceleration and speed.

With resistor controllers, such as those supplied in race sets and the aftermarket versions, the resistance value, measured in ohms, needs to match the demands of the car's motor and magnet combination. The hotter the motor and the more powerful the magnet the more current the motor will draw and the lower the required resistance for optimum control. If your controller has too little resistance the car will take off at full speed when the trigger is pulled only part way back. If the resistance is too high you will have to pull the trigger some way back before the car moves at all. Either way you have only a small proportion of the trigger's travel over which to vary the speed of the car and you don't have full control. If you drive a variety of cars with widely differing resistance requirements you will need several different controllers to cover all of them properly. No adjustment is possible with a resistor controller.

The great advantage of electronic controllers is that one controller will allow you to drive cars with differing motor and magnet setups with equal effectiveness. They all have a variable sensitivity adjustment and you can usually adjust other parameters such as the amount of braking and the rate of acceleration.

Resistor Controllers

If you intend to run only box standard Scalextric type cars on your home track and cost is a major factor then an aftermarket resistor controller of 25 or 45 ohms will do the job at around £30/£40. They will not be ideally matched to all your cars but will give adequate, if not perfect, control. Parma and DS Racing Products make good quality resistor controllers that come wired with the necessary plugs for all the currently available track systems although Parma ones are in short supply at the time of writing.

Electronic Controllers

If you run a variety of motors and/or want to be able to adjust controls to your liking then electronic controllers are highly recommended and probably essential if you want to be competitive at your local club. Truspeed, Professor Motor and Slot.It are popular choices and start around the £90/£100 mark. It is perfectly possible to spend three times as much for top of the range models with all the bells and whistles but unless you are involved in top flight competition at national level it is unlikely you will gain any real benefit from these.


A recent innovation has been the appearance on the market of wireless electronic controllers. Scorpius has been available for some while but other manufacturers have versions under development. They are more expensive but very handy if you don’t want to be restricted to one control position.

Find out more

We have a review of the Scorpius wireless controller on the forum
Scorpius wirelless controller review

Controllers from Pendle Slot Racing