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Stop watch switch manual

Bob barjam

New Member
Hello I know nothing about electronics. Need your help.
I am inventing a timer and need to attach a switch on a rope. The switch would stop a stop watch timer perhaps on a wrist.
I need the switch to be tiny and it only needs to stop the watch timer when tripped.
the distance to the watch from switch is only about 20 feet.
The switch would be cylindrical and thin so maybe without a battery. Perhaps a push button that would be triggered when the rope is taught.


Active Member
can you give a little more description please?

how is this supposed to work?(in detail)

What is this for?

is it stopping a wrist watch? Or the built stop timer you implied?

This seems like a mechanical problem and not as much an electrical one.
Have you looked up simple timer circuits? I should be fairly simple to trigger it by a latch or whatever you were wanting.


Well-Known Member
Most Helpful Member
What is the size and length of the "rope" (ie. how much will it weigh), what orientation (eg. vertical or horizontal), and is it only supported by the switch?

How much force should be required to trigger the switch? If it's a vertical rope hanging on the switch, how much force should it be able to stand without pulling away from the switch (eg. breaking things).
Is it OK if it just detaches when pulled, or must it be "self resetting" so it works every time the rope is pulled.

As Billybob says, it's a mechanical layout problem and deciding on a suitable switch type depend on a lot of parameters.

It could be as simple as a jack plug attached to the string/rope that pulls out a jack socket & allows a contact to close, or a magnetic reed switch with a magnet attached to the rope - but the type depends on the physical layout and minimum/maximum forces etc.


Well-Known Member
Most Helpful Member
Google "clothespin switch". :) Simplest way to do what you likely want to do.


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