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The TMB-1 is an RF amplifier unit / receiving accessory that can be used with a low-impedance broadband loop, a high-impedance terminated loop (such as a Pennant, Flag, or Kaz Delta), and whip (telescoping rod) antennas.

QST Article on what you should know about matching networks for class C RF power amplifiers

low-noise amplifier for HF reception, amplifies signals 80 to 100 times between 0.15 MHz and 30 MHz. It will let you hear more signals with your RTL-SDR plus Ham-It-Up setup

This program simplifies the design of the single-ended Class E amplifier. Operation is intuitive and encourages "tuning" and exploration.

Schematic diagram of the VLA 200 power amplifier by RM Italy

VHF Power amplifier VLA 200 english manual

4CX1500B RF amplifier schematic, working 1.8 MHz to 29.7 MHz

IC8POF's How To index, Hamradio mods, Crazy PA Tuner project (transform any manual amplifier in an automatic one).

An improved version of DK9NL QRM Killer, with dedicated noise sampling antenna for completely filtering of plasma TV rattle on HF bands

K6ODV Six Meter KW Amplifier Designs

Relay substitution tutorial, power amplifier tuning and Technical Characteristics

QST Magazine Product Reviews - Key Measurements Summary - HF-Transceivers or Receiver and Linear Amplifiers

Here is a simple, self-contained beacon which can run a few milliwatts or as much as a watt depending on choice of amplifier and supply voltage.

Linear Amp UK specializes in the design and production of high-quality linear amplifiers, offering models for HF, VHF, and UHF amateur and commercial applications. The company emphasizes nearly 30 years of experience in crafting each unit, ensuring robust performance and longevity. Their product line includes amplifiers engineered for a 100% duty cycle, promoting continuous and reliable operation across various modes. The amplifiers feature solid, dependable designs, ensuring quiet and effortless performance during transmission. Each unit is hand-built to stringent standards, reflecting a commitment to durability and operational stability. All products are CE approved, confirming compliance with European safety and environmental directives, and come with a standard two-year warranty, providing assurance to operators. Key specifications often include coverage for 1.8-30MHz (WARC bands), 50MHz, 70MHz, and 144MHz, utilizing tubes such as 811, 572, 811A, 572B, GS35, GS35B, 8877, 3CX1500, and _3CX1500A7_ in their designs.

What makes a good solid-state amp ? by Adam Farson, VA7OJ/AB4OJ, May 2002

ON6MU Low Power amplifier

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

The Pecker is a software application that emulates an existing hardware amplifier tuning aid operated in SSB mode as apposed to CW or AM. As such no carrier is used by G7EIX

A page dedicated to Yaesu FL-2100Z linear amplifier for amateur hf bands

Amplifier repair and conversion, specialize in converting HF amplifiers to operate as monoband amps on 50 MHz

Specialize in engineering, design and repair of all rf equipment. Dealer for two way radios, scanners, shortwave radios, wi-fi antennas, wifi amplifiers. Based in Fortuna, California.

The Ameritron ALS-600 600-Watt HF Power Amplifier review by AD5X

Pictures of a monoband linear amplifier for 40m band - 2 x QB5/1750 made by 9A6A

An easy to build with a cheap HEMT FET Transistor Low noise preamplifier with FHX35LG based on JH0WJF design

AL-811 and AL-811H specifications and information about this 600-800 Watt ham radio ower amplifiers

Mark Connelly, WA1ION article on Medium Frequency Amplifier Circuits in PDF format, include some RF amplifier schematics

Demonstrates a range of specialized radio frequency equipment and consulting services for amateur and professional applications. The offerings include _Vector-Finder_ direction finding antennas, various test equipment such as _gate dip meters_ and RF sniffers, and communications receiving adjuncts. Additionally, the company produces satellite antennas for weather satellite reception, voice amplification devices like the _Flex-Mike_, and custom prototype circuit boards. The company's product line addresses needs for precise RF measurement, signal detection, and specialized antenna systems, particularly for direction finding and satellite communications. Their historical association with National Radio (HRO) suggests a legacy in radio technology. The site also highlights a subsidiary, Sierra Mountain Products, which offers outdoor recreational gear, indicating a diversification beyond core RF manufacturing.

Two coupled PAs with each 2 times 2C39 deliver around 400W RF.

This test circuit is easy to duplicate, and demonstrates the extreme voltages that appear in an amplifier when the load is improper for the amount of drive power applied.

100 W output RF amplifier for 10 meter band project by W4NFR

Design and manufacture application specific microwave and RF amplifiers, upconverters, downconverters and multifunction assemblies.

A complete restoration of a Heathkit SB-200 HF power amplifier

Understanding Solid State Linear Amplifiers

How to connect and key Power Amplifiers to Kenwood TS 590 or TS 990. How to home made custom Remote cable to key power amplifiers by JG1VGX

Download the official IC-705 RF direct sampling VHF, UHF, HF, D-Star all mode 10W QRP portable transceiver. Pre-release information in a PDF file all in English.

Homebrew Tubes/LDMOS amplifiers, Antenna, accessories, adventures in 9Q, DX, UN missions, Contests, and more.

Windows signal function generator sotfware, offers 4 main channels, 4 modulators, 1 measurement generator, 1 frequency standard generator, Amplitude, phase and frequency modulation, can generates real band-limited signals

This project is an interface box for the Yaesu FT-817 that includes a band output port, a computer serial interface, and a remote interface for the FL-7000 solid state power amplifiers.

HobbyPCB.com provides quality products and boards for amateur radio including the popular HARDROCK 50 amplifier

Improper tank adjustment and excessive drive are equally harmful to component life, and either can create splatter

Projects you can build, an amplified shaped sine-wave oscillator

1500 watts of RF output on the 70cm band requires robust amplifier design, a challenge addressed by this project featuring the GS-23b / 4CX1600U Svetlana tube. The resource details the construction of a high-power UHF amplifier, providing insights into component selection and layout necessary for stable operation at these frequencies and power levels.

Constructing a high-power 70cm solid-state amplifier presents unique challenges, particularly when aiming for 500 watts output using modern LDMOS devices. This resource details the author's experience building a 70cm amplifier based on a _Freescale MRFE6VP5600H_ transistor, initially from an RFHAM kit. It meticulously outlines the necessary modifications to achieve advertised performance, including optimizing input and output matching, correcting bias circuitry, and ensuring proper output balun connections for stability. The author shares specific adjustments, such as trimming the prototyping board for better transistor fit, drilling additional mounting holes for improved heat sinking, and replacing original matching capacitors with a single _20pf MIN02 metal mica_ for superior output. A critical fix involved jumpering gate decoupling pads to balance the push-pull transistor halves, which increased output to 580W and improved IMD. The resource also highlights a crucial correction to the output balun connection, initially reversed in the _Dubus_ article schematic, which resolved intermittent stability issues. Test results are provided, showing input power, output power, and drain current at 50V, demonstrating the amplifier's performance after modifications. This practical account offers valuable insights for hams undertaking similar high-power UHF amplifier projects, especially those working with LDMOS devices and kit-based constructions.

A 50MHz kW Amplifier by Goran Grubishic, 9A6C

Collection of Kenwood TL-922 linear amplifier modifications

A simple free running oscillator oscillating at the receiver\'s IF (intermediate frequency) beats with the incoming signals in either CW or SSB and the resultant audio frequency goes to the AF amplifier.

A well documented PDF document containing picture sequence taked during the repair of an Icom IC-7700 HF transceiver power amplifier module

Optimizing weak signal reception on the HF bands, particularly in the presence of strong local QRM, often necessitates specialized receiving antenna systems. This resource details the _HI-Z Antennas_ product line, focusing on phased vertical arrays designed for superior noise rejection and directivity. It covers components such as the 4-Square and 8-Element array controllers, which allow for rapid switching of receive patterns, and dedicated low-noise preamplifiers to improve system sensitivity. The site also presents various bandpass filters, crucial for mitigating out-of-band interference and enhancing the dynamic range of the receiver. The HI-Z systems are engineered to provide significant front-to-back and side rejection, often yielding **20-30 dB** of attenuation to unwanted signals, which is critical for DXing and contesting. Users can achieve a notable reduction in local noise, allowing for the discernment of signals that would otherwise be buried. The array controllers facilitate quick pattern changes, enabling operators to null out interference or peak weak signals from distant stations, effectively extending the reach of their receive capabilities by improving the signal-to-noise ratio.

Excellent article and guide to choose the best RF power amplifier that fit your needs by ON4SKY

A collection of modifications and improvements to the Ameritron ALS-600 ham radio RF power amplifier