Phones, Cell Phones & Wireless Telephony

Telecommunications devices, including cell phones, satellite radio or Voice over IP, connect us to one another and to the world of information at our fingertips. Learn all about the technologies we depend upon for efficient communication.

Topics to Explore

Learn More / Page 9

What do the yellow and black wires in a home telephone jack do?

With all the different colored wires used in communications, what do the yellow and black wires in a home telephone jack do?

Phones / Home Telephones

How do digital answering machines work?

What exactly are the components of a digital answering machine? How does voice get recorded? And then, how is it played back on demand?

Phones / Home Telephones

Why am I not allowed to use my cell phone in airplanes or hospitals?

You're probably well-aware of the restrictions related to cell phone and laptop use on airplanes. But do you know exactly why they're in place?

Phones / Cell Phones

Is it possible to detect if someone is illegally using my phone line?

It's possible and relatively easy for someone to tap into your phone line, especially if you live in a dorm or an apartment building. It's also pretty easy to detect. Find out how to tell if your phone line is tapped.

Phones / Home Telephones

What is the difference between analog and digital cell phones?

There are two popular digital systems in the United States. One is generically known as "digital service," and the other is clearly branded as "PCS."

Phones / Cell Phones

What does 900 MHz mean in a cordless phone?

I've been looking at cordless phones and have noticed that this area has gotten fairly complicated! For example, what is the difference between 900 MHz and other systems?

Phones / Home Telephones

What is digital spread spectrum as used in cordless telephones?

Digital spread spectrum (DSS) technology has its roots back in World War II and has evolved into the technology of choice for the cordless phone. Cordless phones are now truly "ready for prime-time" thanks to affordable DSS technology.

Phones / Home Telephones

Inside a Cell Phone

On a "complexity per cubic inch" scale, cell phones are some of the most intricate devices people play with on a daily basis. Take a look inside a cell phone.

By Marshall Brain Phones / Cell Phones

How Telephones Work

Telephones are one of the greatest technological advances of our time. Do you know how your call gets to its destination? Learn all about how the telephone works in this article.

By Marshall Brain Phones / Telephone Technology