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How is the best way to make a cup phone? Answered

I want to make a cup phone that can go around in different bedrooms.


It won't work if it has to turn corners. If the string touches anything then it won't work. A cup phone works by vibrating the string so it vibrates the other cup. IF anything touches the string then it won't work. You need to look into building a small battery powered intercom. You can make it with as many "stations" that you need.

nice suggestion (although you forgot to mention signal attenuation as a station limiter) Still, a nice solution to corners

How am I going to do that? Can you go into more detail.


Here are some links that explain the circuit.

Start here.

Link one.

Link two.

link three.

link four.

Looking at the diagrams you should be able to see that most any amp will work, what's different is the switching that make one the listener and the other the mic.  And the opp. in the other case.

And I like orksecurity's idea of making the electronic version look like the old fashion cup and string version.

Hm. Build an electronic intercom and disguise it as a cup-and-string phone? (Or, maybe more elegant, as an old-style speaking tube system...)

IF you want it to go round corners rather than use string use a suitable length of polythene tubing. This need not be a big diameter so not expensive. Attach to the bottom of your cup - may work better if you make a hole through the bottom first.

Before electronic intercoms, some systems did use tubing -- all those old movies you've seen where the ship's captain uncaps a pipe and shouts into it, for example. (The cap, by the way, acted as a whistle; to get the attention of the person on the far end of the pipe, you blew into it hard to sound the whistle.) While I sorta like the idea of reviving this ancient technology, I still think it'll be easier to install if instead you build something electronic and disguise it as the older approach.

Are you looking for http://www.google.com/search?q=cup+and+string+phone