Build Your Own Rotary-Dial Cell Phone

hwestiii writes "Yet another indicator of how unrepresentative of the main Slashdot crowd I am (meaning 'old') is that, like vinyl records, 8-track tapes, and Pintos, I can remember when rotary dial phones were items of everyday use, and not some object of retro-cool pseudo-nostalgia. Imagine my delight, then at finding this project in which an old rotary phone is turned into a cell phone. To give credit where its due, I originally found it linked from Hack A Day. I know nothing about home-built electronics projects, but this is enough to make me want to learn. If this catches on, imagine what they'll have to do to those 'turn off your cell phone' messages that play in movie theatres."

Comments

What the hell kind of phone is THIS?

[IO ERROR]

What really makes me sad is the knowledge that many people today have never even seen a rotary phone, let alone used one.

If, however, on the off chance you find yourself stranded in South English, Iowa, where the only pay phone in town is still rotary, this is how it works.

Pick up the phone and wait for dialtone. Insert a dime. (Yes, this phone still costs a dime!) Now, see the holes arranged on the disc? Find the one corresponding to the digit you want to dial, insert your finger, and rotate the disc clockwise until you hit the stop. Remove your finger. Wait for the dial to rotate back to its original position. Repeat as needed.

While you were dialing, did you hear those clicks? The circuit is actually being interrupted at a rate of 10 times per second. (This will be 20 times in some other countries.) The switching equipment in the central office measures the number of clicks and the time in between them to determine the number you dialed.

For more information, I suggest reading old articles of Phrack.