What Are Rotary Dial Phones and How Do They Work?

Interesting Engineering ^ | 6/5/21 | Christopher McFadden

[DallasBiff]

The rotary dial phone was once the be all and end all of the telephones. Like the cellphone of today, everybody had one, and they ruled domestic communications for decades.

But that all changed in the 1980s when they were supplanted by a new upstart, push-button telephones. Their days were numbered (pun intended).

Many born after the 1990s have likely never seen one, which is a shame. But for those who do remember, join us as we take a trip back in time in remembrance of this glorious piece of telecommunications history.

[MayflowerMadam]

“To call some one you would dial 5 numbers.”

Grandpa B was 927J2.
Grandpa W was 903R1.

You didn’t dial — no dials. You just picked up the receiver and told Mabel.

[Texas resident]

Junior Sample: BR 549

[Texas resident]

A stick shift is one of the best anti theft devices for millenial car thieves. I have a couple of old VW bugs and I have no concern that they will be stolen.

[T.B. Yoits]

I don’t see why people keep saying that phones ring when they don’t. And what’s this “hang up” business, anyway? Hang it up on what?

Business phones, both digital and Voice Over Internet Protocol (VOIP), still have a cradle and ringers.

Outside of that, companies make retro versions of the old candlestick phones. Some are cellular and some work with Bluetooth technology.

[Celtic Conservative]

Perhaps I got the number wrong... but there was a number for time and weather.

CC

[willgolfforfood]

I had a 2- digit phone number as a kid. Two girls my age had a 1- digit phone number. It was 9.

[T.B. Yoits]

In my area, they deactivated all of the land-line outlets when Fios came in. How would I use my old phone here without converting it somehow?

Your Fios box should have the regular phone interface so that all your existing phone wiring can be connected to an analog phone.

[T.B. Yoits]

I think there was a secret number that would tell you the phone number you were calling from...

Absolutely. I don't recall it but it was used on every job site before mobile phones. As a home or building was going up, the first contractor after the phone service was established would connect to a jack and call the number. He'd write the number on the wall so the other contractors could have their shops call the site.

[T. Rustin Noone]

We moved from New jersey to Cape Cod when I was 3 years old.

The only phone in the house was a black bakelite model with no dial.
To operate it, you just picked it up, put it to your ear, and
a woman named Helen would ask you who you wanted to be connected
to. Our number was Chatham-499. A few years later the phone company
delivered a black phone with a dial, but the dial was not functional
for at least two years. Then one day, my three brothers and sisters
and I were instructed on how to use the dial. Then we were
told that we were not allowed to use the phone. Eventually, our
number became 945-0499. Calling the next town was ok. Two towns
west and it was a long distance call, even though you could drive there in
15 minutes.

Maybe I have lived just long enough.

[T.B. Yoits]

69. Now, I think it’s *69

That retrieves the number of someone who called you, not the number you were calling out from.

[Jamestown1630]

Yes.

[Jamestown1630]

My goodness! I’ll have to get the Husband Unit working on this...

Thanks!

[T.B. Yoits]

I’m looking at my Verizon Fios router and it has a jack on the back that connects to the analog phone wiring.

[Myrddin]

How in the world could the exchanges take those pulses and connect thousands of callers to their destinations all at once with bunches of relays?

A very carefully crafted network of switches and trunks. Off-hook activates a "line finder" in a Strowger switch. As the first number is dialed, the switch armature ratchets upward, then rotates to another Strowger switch to the next number. On the 3rd number, the switch finds a "trunk" to another exchange. A line finder on that exchange goes through a set of 4 Strowger switches to land on the terminating subscriber line. For "long distance", the +1 jumps right on a switch very high in the hierarchy and steps down to the destination. Next generation switches were "crossbar" with "fine motion" versus the large motions of the Strowger switch. Finer crossbar switches were employed at "toll" offices to make "long distance" call. The limiting factor for this kind of telephone network is the need to have a fully dedicated wire path end to end. In the digital age we can queue/buffer information, speed up transmission rates and leverage switch fabrics with very high capacity in a smaller physical space.

[fr_freak]

LOL, those old phones were heavy, and if someone would slam the phone the bell would always ring

And the bell had two settings - loud and soft, determined by a little slide switch on the side of the base. The soft setting would still ring loud enough to make you jump, especially at night, but the loud setting would damn near shatter glass.

[null and void]

It was POPCORN 767-2676

[Myrddin]

Bell Labs had lots of money at that point in time. I was with Pacific Telephone through divestiture, then Pacific Telesis until Nov 1991. The MBAs talked the company into dumping the 5,000 employee software support part of PacTel. In short order they were unable to perform in 180 of 360 projects underway. Eventually they were swallowed up by SBC. It was clear there was no future after the bloodletting. I had a written offer from my current employer hand delivered in Nov 1991. A simple decision. Approaching 33 years in December.

One of our other luminaries at PacBell was Scott Adams. He did just fine exiting for a new career.

[old-ager]

> I think you could dial Operator that way, but would you tap 10 times?

Yup, 0 was ten interruptions. Also evident from its position above 9.

[Jamestown1630]

Ok. We’ll try it.

[Jamestown1630]

I just remember getting Operator didn’t take that many pings.