Inline speed switch.

191

02:53:20

I found this in a dead water toy, don't know how it works, any help?

published 4 years ago

alexpu

4 years ago

Think of the transistor like a water tap, and the potentiometer like the valve. As you lower the resistance on the transistor base by turning the pot, you're opening the valve allowing more water to flow through (or in this case voltage). The capacitor is there to smooth out the changes to the flow. Check out this copy of your circuit: https://everycircuit.com/circuit/6069245592731648 if you turn the pot on the copy without the capacitor you can see the voltage change is kinda choppy.

tooshy

4 years ago

I ment how is the pot grounded.

tooshy

4 years ago

I know the basic of how it ajusts, but not so much how it grounds throw the load

alexpu

4 years ago

The pot's path to ground is through the base of the transistor. You could leave the other side of the pot floating and it will still function. With the cap there the only time any current flows at all is when there is a change to the voltage.

alexpu

4 years ago

https://everycircuit.com/circuit/5086946172600320

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