RF Amplifier Circuits

  

A linear amplifier is an electronic circuit whose output is proportional to its input, but capable of delivering more power into a load. The term usually refers to a type of radio-frequency (RF) power amplifier, some of which have output power measured in kilowatts, and are used in amateur radio. Other types of linear amplifier are used in audio and laboratory equipment. An RF linear amplifier can be based on either solid state or vacuum tube technology.

Most commercially manufactured one to two kilowatt linear amplifiers used in amateur radio still use vacuum tubes (valves) and can provide between 10 to 20 times RF power amplification. For example, a transmitter driving the input with 100 watts will be amplified to 2000 watts (2 kW) output to the antenna. Solid state linear amplifiers are more commonly in the 500 watt range and can be driven by as little as 25 watts. However, AM radio broadcast transmitters of up to 50 kW are now solid state.
 
Large vacuum valves are still used for international long, medium, and shortwave broadcast transmitters between 500 kW up to 2 MW. The basic applications of the RF power amplifier include driving to another high power source, driving a transmitting antenna, microwave heating, and exciting resonant cavity structures. Among these applications, driving transmitter antennas is most well known. The transmitter–receivers are used not only for voice and data communication but also for weather sensing (in the form of a RADAR).
 
Microwave or RF heating is an industrial application which is also benefiting our homes in the form of microwave ovens. Class-A operation is characterized by a constant DC collector (or drain) voltage and current. This class of operation is required for linear amplifiers with severe linearity requirements including: Drivers in SSB transmitters where a 2-tone 3rd-order intermodulation of at least -40 dB is required. Drivers in TV transmitters where the contribution to the gain compression must be very low, i.e. not more than a few tenths of a dB.
 
 

 

 

News

MaxLinear Introduces MxL9162 64Gbaud Linear Transimpedance Amplifier for Next-Generation 400Gbps / 600Gbps ...

MaxLinear Introduces MxL9162 64Gbaud Linear Transimpedance Amplifier for Next-Generation 400Gbps / 600Gbps ... Business Wire (press release) CARLSBAD, Calif.--(BUSINESS WIRE)--MaxLinear Inc. (NYSE: MXL), a leading...

Mar 20, 2017

Gunn diode

Hackaday Gunn diode Hackaday A tunnel diode amplifier circuit . Chetvorno [CC0] Particularly if your textbook is a little older, you may find a short section talking about the tunnel diode. There will be an...

Mar 21, 2017

Poulsen arc

Hackaday Poulsen arc Hackaday A tunnel diode amplifier circuit . Chetvorno [CC0] Particularly if your textbook is a little older, you may find a short section talking about the tunnel diode. There will be an...

Mar 21, 2017

Day: March 21, 2017

Hackaday Day: March 21, 2017 Hackaday A tunnel diode amplifier circuit . Chetvorno [CC0] Particularly if your textbook is a little older, you may find a short section talking about the tunnel diode. There will be an...

Mar 21, 2017

MFG-2000 RF Function Generators come with 100kHz power amplifier channel.

ThomasNet News (press release) (blog) MFG-2000 RF Function Generators come with 100kHz power amplifier channel. ThomasNet News (press release) (blog) Channels 1 and 2 provide high-performance arbitrary function...

Mar 6, 2017

MaxLinear Introduces new transimpedance amplifier

MaxLinear Introduces new transimpedance amplifier FinancialNews.co.uk (blog) MaxLinear Inc. (NYSE: MXL), a provider of radio frequency ( RF ), has introduced the MxL9162, a 64Gbaud linear coherent transimpedance...

Mar 23, 2017

Qorvo adds new Spatium amplifiers for electronic warfare systems

Qorvo adds new Spatium amplifiers for electronic warfare systems Semiconductor Today Qorvo Inc of Greensboro, NC, USA (which provides core technologies and RF solutions for mobile, infrastructure and defense...

Mar 6, 2017

Qorvo® Powers Electronic Warfare Systems with New Spatium® Ultra-Broadband Amplifiers

Qorvo® Powers Electronic Warfare Systems with New Spatium® Ultra-Broadband Amplifiers GlobeNewswire (press release) GREENSBORO, N.C., March 02, 2017 (GLOBE NEWSWIRE) -- Qorvo ® (Nasdaq:QRVO), a leading provider of...

Mar 2, 2017

Off-the-air reception guide for 12 News

12news.com Off-the-air reception guide for 12 News 12news.com 4.) If you have splitters, install termination end caps on any unused splitter outputs. 5.) Do have a RF amplifier inline? Make sure it is...

Mar 10, 2017

MaxLinear Launches MxL9142 45Gbaud Linear Transimpedance Amplifier for Telecom and Data Center Coherent ...

MaxLinear Launches MxL9142 45Gbaud Linear Transimpedance Amplifier for Telecom and Data Center Coherent ... Business Wire (press release) CARLSBAD, Calif.--(BUSINESS WIRE)--MaxLinear Inc. (NYSE: MXL), a leading provider...

Mar 16, 2017

Units & Modules