Activity 3.5 – Transistor Research Webquest

Purpose

In the 1980s, there was a popular television show that featured an actor who had bionic hearing. Supposedly, a group of doctors embedded an implant into her head that enabled her to hear whispers coming from inside buildings. How could that work? If you have ever looked at a hearing aid, you would notice that most have a tiny transistor in them that has a programmable chip. That allows the audiologist to program the hearing aid to pick out and amplify certain sounds that fall within the loss of hearing range. In honor of their namesake, Alexander Graham Bell, a lifelong advocate for the hearing impaired, Bell Labs waived the patent royalties for hearing aids.

In 1954, the transistor became part of popular culture with the sale of the first transistor radio. IBM announced it would no longer use vacuum tubes in its computer designs by announcing IBM’s first, fully transistorized computer. That machine had 2000 transistors. By the late 1950's, the transistor became an integral part of the electronic telephone switching system, as well as a key component of other important products and services, such as portable radios, computers, and radar.

Transistors can be used as a switch or as an amplifier. The term transistor is derived from the two words, transfer and resistor. A transmitter transfers resistance. They can draw more current of less current. This is often referred to as sink current or source current.

In this activity, you will research transistors using the internet andlearn about their different uses.

Equipment

  • Computer with internet access

Procedure

  1. Go to
  2. Read about the transistor at this web site and complete the graphic organizer below.
  3. When you are finished, turn it into your teacher for evaluation.

Conclusion

  1. What is the difference between a transistor being used as a switch and as an amplifier?
  1. What are semiconductors used for?

Project Lead The Way®

Copyright 2005

GTT – Magic of Electrons - Activity 3.5 – Transistor Research WebQuest– Page 1

What is a semiconductor?

Project Lead The Way®

Copyright 2005

GTT – Magic of Electrons - Activity 3.5 – Transistor Research WebQuest– Page 1