engineering

William H. Doherty

William H. Doherty is a engineering topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand William H. Doherty rather than just read about it. In short: William H. Doherty (August 21, 1907 – February 15, 2000) was an American electrical engineer noted for his invention of the Doherty amplifier.

Key takeaways

William H. Doherty belongs to engineering; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect William H. Doherty to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of William H. Doherty from memory before moving on to harder problems.

Reference excerpt

William H. Doherty (August 21, 1907 – February 15, 2000) was an American electrical engineer noted for his invention of the Doherty amplifier. Doherty was born in Cambridge, Massachusetts, received his B.S. degree in electrical communication engineering in 1927 and M.S. degree in engineering in 1928, both from Harvard University. After a few months in the American Telephone and Telegraph Company Long Lines Department in Boston, he joined the National Bureau of Standards to study radio phenomena. In 1929 he began work at Bell Telephone Laboratories where he developed high-power radio transmitters for transoceanic radio telephones and broadcasting. In 1936, he invented a means to greatly improve the efficiency of RF power amplifiers, which was quickly termed the "Doherty amplifier" (U.S. Patent 2,210,028). It was first used in a 500-kilowatt transmitter made by Western Electric Company and proposed for WHAS, Louisville, Kentucky, but the Federal Communications Commission restricted broadcast stations to 50 kilowatts maximum power, and WHAS would go on to install a 50,000 watt Western Electric Doherty transmitter. By 1940, Western Electric had incorporated Doherty amplifiers in 35 commercial radio stations worldwide, nearly all of these at the 50,000 watt level, and employing a 5,000 watt driver of conventional design. Post-World War II Western Electric would offer 5,000 and 10,000 watt Doherty transmitters, and several were installed in the United States as backup transmitters for Class I (now Class A) stations, and a few as main transmitters for Class II/III (now Class B) stations. Doherty received the 1937 IEEE Morris N. Liebmann Memorial Award for his improvement in the efficiency of radio-frequency power amplifiers.

Selected works Doherty, W.H. (September 1936). "A New High Efficiency Power Amplifier for Modulated Waves". Proceedings of the IRE. 24 (9): 1163–1182. doi:10.1109/JRPROC.1936.228468. US Expired US2210028A, Doherty, William H., "Amplifier", published 1940-08-06, assigned to Bell Telephone Labs

References Proceedings of the IRE, 1937 Radio Broadcasting at 500 kilowatts, by James E. Brittain Microwaves 101 William H. Doherty's obituary

Worked examples

Example 1 — a first encounter with William H. Doherty

Start with the simplest possible case. Write down what William H. Doherty claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In engineering, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to William H. Doherty before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about William H. Doherty ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of William H. Doherty

In research: William H. Doherty appears in engineering research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses William H. Doherty in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: William H. Doherty is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1907 births, 2000 deaths, 20th-century American engineers, so understanding it makes those chapters shorter.
In everyday life: Look for William H. Doherty outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “William H. Doherty” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study William H. Doherty in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what William H. Doherty means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain William H. Doherty out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is William H. Doherty in simple terms?

William H. Doherty (August 21, 1907 – February 15, 2000) was an American electrical engineer noted for his invention of the Doherty amplifier.

Why does William H. Doherty matter?

Because it connects several engineering ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study William H. Doherty?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on William H. Doherty.