#### bigal_scorpio

##### Active Member

I am trying to figure out if it would be feasible to make a device that could test the length of cables with any degree of accuracy.

My idea was that I may be able to measure the speed the electrons take to make a circuit on a given length of wire and with a bit of maths then use this as a formula to work out how long an unknown length was, single core would need both ends connecting to the device of course so the time would be right and with multiple cores any two could be joined and then the result halved. Or is it that simple?

The problem I have is what would I need for accurate measurement of such tiny times or is it even possible with ordinary run of the mill ICs like PIC or such.

I have seen meters on line for doing this but I assume they must work by capacitance or something as they can detect open circuits and breaks.

Anyway if anyone has any ideas or further info they can point me to I would be grateful.

Thanks for looking........Al