Here's a short story:

A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits. 

The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. First conceived by Julius Lilienfeld in 1926 and practically implemented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley, the transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement. (End of story)

Provide your best guess for the following question. Give ONLY the guess, no other words or explanation.

For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>

Here are a few examples of questions and answers:

Question: What is one use of a transistor?
Guess: integrated circuits

Question: What is a transistor in relation to modern electronics?
Guess: the fundamental building block

Question: In what year was it conceived?
Guess: 1926

Question: By whom?
Guess: Julius Lilienfeld

Question: How many years later was it implemented?
Guess: 1926 and practically implemented in 1947

Question: How many scientist were involved in implementation?
Guess: John Bardeen, Walter Brattain, and William Shockley 3

Question: What field did the invention revolutionize?
Guess: electronics

Now answer the following question in the same format.

Question: And what two types of radios were developed after its implementation?

cheaper