Help for Newbie Please

[clivcroucher]

Hi all

I have a small project which is driving me nuts! OK I bought my two boys a slot racing set for Xmas. Its a small set that just unfolds in a case, plug in two controllers and your off racing.

The controllers are hand powered, as in turning a handle generates the voltage in a simillar way to the hand powered torches out there. One of my boys has cerebral palsy and he cannot rotate the handle fast enough to generate enough power to keep the car moving round the track.

So..........I though easy solution, I'll make a battery powered hand controller for him that he can simply turn a knob on to increase the speed of the car.

I measured the voltage and current being used, a bit hit and miss but something in the order of 3 - 9v @ around 0.5 amps.

Here's my difficulty..........I cannot find a rheostat or pot that will work with this low DC voltage. I'm in the UK and have tried the major retailers for these parts. it is driving me insane! Not even Ebay has come up trumps.

So my question........can I achieve what I set out to? Is there a better way to do it?

Obviously I do not want to spend a fortune on expensive parts......I thought I would crack this for less than £10.

Any help wuould be much appreciated.

Thanks
Clive

 

[Harald Kapp]

Hello Clive,
can you get your hands on a spare grip-controller for slot racing cars? All you'd have to add is the battery.
If you are more into building one yourself, you can buy suitable rheostats as spare parts for slot racing, e.g. here: http://www.pendleslotracing.co.uk/html/powerandcontrol/mbslot.htm.

I suggest you use a transformer instead of a battery. A typical 9 V battery has a capacity of approx. 500 mAh - 600 mAh. At 0.5 A this cell will be discharged within 1 hour of use. A rechargeable battery has even less capacity, though it has the advantage of being, well, rechargeable.

Regards,
Harald

 

[clivcroucher]

Harald

Many thanks for your reply. I did wonder how long the battery would last but don't know enough about this stuff to work it out. A transformer looks the better option!

Good idea about the spares/build......I'll look for something like that locally.

Cheers again
Clive

 

[Harald Kapp]

Like her:; http://www.ebay.co.uk/sch/i.html?rt...Cars_ET&_fln=1&_ssov=1&_trksid=p3286.c0.m1539

Harald