Rotary Dial
A rotary dial is a mechanical device that is used to make telephone calls It consists of a circular disc that is mounted on a switchboard and has a series of holes or slots in it. When the disc is turned, it causes the holes to line up with the contacts on the switchboard, which then connects the call.
The rotary dial was invented in 1893 by Almon Brown Strowger, an undertaker from Kansas who was fed up with competing against the local telephone exchange operator who was diverting his calls to a rival. He designed the rotary dial in order to make it easier to connect calls and eliminate the operator’s ability to control them. The rotary dial became the main device for dialing telephone numbers until the introduction of touch-tone phones in the late 1960s.
While the rotary dial may have been replaced in most households by newer technology, it is still used in a few places today. Here are five examples of its use:
1. Landline Phones: Today, many landline telephone systems still use rotary dials for dialing phone numbers. This is because these systems are not compatible with touch-tone phones and it is still the simplest and most reliable method for connecting calls.
2. Emergency Call Boxes: Emergency call boxes located on the side of the road or in other public places are often equipped with rotary dials because they are simple to use and very reliable.
3. Medical Devices: Medical devices such as defibrillators, heart monitors, and other life-saving equipment often use rotary dials to input settings and adjust settings.
4. Telephone Exchange Systems: Many telephone exchange systems, such as PBX systems, still use rotary dials for dialing internal telephone numbers.
5. Vintage Telephones: Vintage telephones, including those from the 1950s and 60s, are sought after by collectors and still use the rotary dial platform.
The rotary dial is a classic example of how technology has evolved over the years. It is a simple yet reliable device that is still being used in certain places today. From landline phones to medical equipment to vintage telephones, the rotary dial remains an important part of our technological history.