We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What Is an RF Power Amplifier?

By Geisha A. Legazpi
Updated May 16, 2024
Our promise to you
EasyTechJunkie is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At EasyTechJunkie, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

A radio frequency (RF) power amplifier is a device that increases the voltage and current of an RF signal. Usually, the RF signal being boosted is an RF carrier with sidebands or a pure carrier or just sidebands in some cases. The RF power amplifier usually has an air-cooled final stage that uses heat sinks with fins that are increased in number to come in contact more with air and cause more heat transfer for a more cooling effect.

There are audio power amplifiers that operate in the audible voice frequencies such as 400 to 4,000 hertz (Hz). High-fidelity audio amplifiers work from around 40 Hz to about 15,000 Hz. RF power amplifiers have specified operating frequencies, and the chosen operating frequency must lie within their frequency range. For an operating frequency of 150 megahertz (MHz), an RF power amplifier with a range of 145 to 155 MHz will be suitable. An RF power amplifier with a frequency range of 165 to 175 MHz will not work on the operating frequency of 150 MHz.

In radio electronics, the RF power amplifier is an electronic amplifier that may be built in a transmitter or may be a separate equipment that is connected by a coaxial cable to the output of a lower-power output transmitter. The RF power amplifier output is then connected to the external antenna. For receiver operation, the transceiver or transmitter-receiver unit may have an internal or an external transmit/receive (T/R) switch. The job of the T/R switch is to switch the antenna to the transmitter or to the receiver as needed.

The RF power amplifier circuit may use transistors or integrated circuits to produce the amplification. In RF power amplifier design, the goals are to have enough amplification to produce the desired output power and to allow a temporary and small mismatch between the transmitter and the antenna feeder and the antenna itself. The impedance of the antenna feeder and the antenna itself is usually 50 ohms. Ideally, the antenna and feeder combination will present an impedance that is purely resistive at the operating frequency.

Most antennas may be tuned so that when combined with the feeder, they present the most ideal impedance to the transmitter. This impedance matching is required for maximum power transfer from transmitter to antenna. Antennas will have slightly different characteristics over the frequency range. The important test is to make sure that the reflected energy from the antenna into the feeder and back to the transmitter is low enough. When the impedance mismatch is too high, the RF energy being sent to the antenna will be returned to the transmitter to produce a high standing wave ratio (SWR) that causes the transmit power to stay in the RF power amplifier and cause overheating and even damage to active components.

EasyTechJunkie is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Link to Sources
Discussion Comments
EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.

EasyTechJunkie, in your inbox

Our latest articles, guides, and more, delivered daily.