In the past, the LEGO trains had a port on the motor to pull power from the tracks so you could run things like lights or small motors for effects.
There was no protection on the direction the power was going, so you could attach it to a motor port of an RCX brick. And therefore you had a programmable brick on the tracks. Side effect was that now the rails are also now powered so every train starts to move...
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In the past, the LEGO trains had a port on the motor to pull power from the tracks so you could run things like lights or small motors for effects.
There was no protection on the direction the power was going, so you could attach it to a motor port of an RCX brick. And therefore you had a programmable brick on the tracks. Side effect was that now the rails are also now powered so every train starts to move...