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VHF and VHF amplifiers including repeater rf amplifiers

A 2 meter power amplifier

Manufacturer of HF transceivers, antenna couplers, antennas, RF Power amplifiers, portable antennas, speakers and other accessories for 28 years.

A 144 MHz kilowatt amplifier project details the construction and performance of a high-power VHF linear using the GU74b tetrode. This Russian tube, equivalent to the Svetlana 4CX800, is noted for its conservative datasheet ratings, performing closer to 800-1000W anode dissipation in practical applications. The design prioritizes compactness and achieves 1.2 kW output with only 20W of drive power, demonstrating a 70% efficiency at 2.5 kV plate voltage. The amplifier has been successfully deployed in demanding _EME_ (Earth-Moon-Earth) operations since June 1994. Challenges encountered during development included achieving stability with a grid-1 input configuration. The author, _CT1DMK_, opted not to publish the full design due to its complexity, suggesting it might be difficult for less experienced builders to replicate successfully. However, he invites direct contact for those with specific interest in the design. Future plans include a "144MHz GS35b compact amplifier" project, promising another kilowatt-plus design. This resource offers insights into high-power VHF amplifier construction and the practical application of specific power tubes.

Manufacturer of big power amplifiers

Strong RF HF power amplifiers made in europe ! Output 2,5KW 4KW PEP, 160m to 10m.

This FET preamplifier has been around for almost 25 years. It is extremely reliable and can handle several watts directly into either the input or the output without failure.

manufactures and distributes HF, VHF, UHF and SHF equipment covering 10MHz. - 47.0GHz. Our products include: Wireless LAN / WAN Bidirectional Linear Amplifiers, Low Noise Preamplifiers - LNA's, RF Linear Amplifiers, Relays, Transverter Systems, Frequency Translation Systems, Downconverters, Antennas, Parabolic Dishes, Coaxial Cable, Relays, Antenna Switches, Microwave Test equipment, PC controlled Receivers, Microwave Linear Amplifiers including models for Telemetry, Wireless, and CDMA applications.

Australian dealer, HF linear amplifiers, power supplies, baluns, HF UHF yagis and verticals including multiband HF verticals.

4CX250B X2 K2RIW style 2m amplifier

RF Amplifiers for HF VHF UHF

This project uses a widely available IRF510 MOSFET, work on HF 80, 40, 30, 20 and 17 meter bands

Solid State and TWT Amplifiers From 1 MHz to 40 GHz with Power Levels from .1 mil Watt to 2.5 Kw

AEA Technology Inc. is a pioneer and leading manufacturer of RF and cable test equipment for the wireless, Telco, CATV, NMR & MRI, RFID, telemetry, aviation, commercial, military, and two-way radio industries. Produces SWR Meters, Pre Amplifiers, filters, power meters and antenna testing products

KD9JQ 2 meter GaAsFET preamplifier by KD9JQ

A 6 meters band amplifier width schematics

Thierry LOMBRY, ON4SKY, develops in three long articles all you need to know about amplification, and how to seletc an HF and a solid-state amplifier, with pictures.

Infomration schematics and pictures about various hf and vhf QRO linear amplifiers

AM/FM/CW QRP RF Power Amplifier for the HF 10 or 11 meterband (28MHz/27MHz)

Technical reference about Accessories, Amplifiers, Antennas, Cable and Connectors, Filters, Geography, Grounding, Gunk, Matching Networks, Projects, Propagation Info Radios, RFI/EMI, Rotors, Station Setup, Towers.

You will find on these pages my experiences and results on antennas and local/non-local QRM/noise reduction. Using a broadband vertical active magnetic loop and a home made / designed broadband amplifier. Two vertical magnetic Alford loops are used in an array. Analog and Digital Signal Processing and a dual phase coherent Software Defined Radio (SDR) are used. By PA0SIM

1500 Watt HF power amplifier

Italian page including pictures schematics diagrams of an home made linear amplifier using four EL509 in parallel. Output power is about 700W.

This site is dedicated to mobile amateur radio operators, old and new alike. Whether you are into HF, or VHF operation, I trust the information presented will increase your enjoyment of our great hobby. With safety as a byword, there are articles on amplifiers, antennas, bonding, impedance matching, installing hardware, mobile equipment, noise and RFI abatement, wiring, and much more. I do my best to keep these articles up to date, and easy to follow.

YU1AW project for a home made QRO PA 144 MHz 20 kW GU36B-1

Source of common model manuals and amateur help on amplifier problems for the amateur bands, Discussion of vacuum tube amplifiers. Technical information and discussion of obselete tube replacement.

Constructing a high-power solid-state amplifier for HF operations presents unique challenges, particularly when aiming for significant output like 600 watts. This project details an amplifier design employing **Motorola MRF150** FETs, a common choice for their robust performance in RF power applications. The design emphasizes achieving substantial power output, a critical factor for effective DXing and contesting, where every decibel can make a difference in signal propagation and readability. While specific circuit diagrams or construction details are not directly presented on the current page, the mention of MRF150 FETs points towards a design that would typically involve push-pull configurations, impedance matching networks, and robust power supply considerations to handle the high current demands. Such amplifiers are often built with an eye towards linearity and efficiency across the HF bands. Amateurs pursuing similar high-power solid-state projects often share insights on thermal management, intermodulation distortion, and component sourcing, all vital for a stable and reliable amplifier capable of delivering 600 watts into a proper antenna system.

by Tony I0JX

HF QRP Linear Amplifier with 2x 2SC2166 + 2x 2SC1969 Push Pull Transistors (13.8V)

The Elecraft K3, a popular HF transceiver, is often benchmarked against new market entrants. This article critically compares the Kenwood TS-590S to the K3, focusing on key technical specifications and operational aspects relevant to serious amateur radio operators. The author proposes three distinct evaluation methods: a circuit diagram comparison, an independent review analysis (referencing Peter Hart, G3SJX, in RadCom), and a real-world "ear test" by experienced contest operators on 40 and 80 meters. The analysis delves into specific receiver components, including the first mixer design, RF and IF amplifier performance, and the presence of an image noise filter. It highlights the K3's switched mixer and the potential for the TS-590S to utilize similar or improved designs, such as a classic filter with enhanced selectivity. The article also scrutinizes the second mixer stage, noting the K3's SA612 chip and its associated IP3 limitations, suggesting Kenwood might achieve benefits with a different mixer architecture. Further points of comparison include DSP capabilities, where the K3's high-performing DSP with KK7P's involvement is noted against the TS-590S's potential reliance on newer IC technology but possibly less refined software. The discussion extends to DDS and PLL implementations for phase noise and spurious emissions, and the utility of a second receiver for DX chasing and contesting, acknowledging its importance for some operators while being less critical for others. The article concludes by emphasizing personal preference in equipment selection.

Demonstrates the construction of a **homebrew spectrum analyzer** designed by Wes Hayward, W7ZOI, and Terry White, K7TAU, enabling radio amateurs to build a capable test instrument without significant expense. The resource details a _double-conversion superheterodyne_ circuit, employing intermediate frequencies of 110 MHz and 10 MHz, and covers essential blocks such as the time base, logarithmic amplifier, resolution filters, and local oscillators. It highlights the use of hybrid and monolithic ICs, including mixers, amplifiers, and VCOs, to simplify construction while maintaining performance. The design supports useful measurements in the 50 kHz to 70 MHz range, with methods outlined for extending capabilities into VHF and UHF. The authors emphasize that this analyzer, while simple to build, is intended for serious measurements, requiring careful control of signal levels to avoid spurious responses. It uses an oscilloscope for display, with specific instructions for calibration and adjustment of various stages, including the log amplifier and IF gain. The guide provides detailed schematics and component lists for each section, such as the 110 MHz triple-tuned band-pass filter, which achieved **90 dB** image rejection, a significant improvement over double-tuned circuits. Practical advice on alignment and troubleshooting is included, drawing on the authors' extensive experience in RF circuit design.

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

On 23cm the best way to obtain a good RX-sensitivity is to use a GaAs-FET in the front-end, since these devices show very low noise figures.

Well documented Amateur Radio HF/VHF antenna projects, high power Russian GS35B RF amplifiers, mobile RFI solutions, related accessories, vintage radios, Six meter equipment, and useful techniques by K8CU are inside.

"Amateur radio equipement; Procom equipement Duplexeur, amplifier , Coax , connecteur microwave equipement"

80m hexfet power amplifier by W7ZOI

Amateur radio accessories, power supplies, tvi filters, speakers, microphones, swr meters, preamplifiers, switches, cable and connectors,

Sams Photofact downloads - Schematics and Service Manuals for Radios, Amplifiers, More

An interface for amplifier to TS-850S

Advanced QRP Low Cost Mosfets HF Linear Amplifier with schematics, IMD, gain data and more. Six articles about amateur radio.

I4FAF etrode Tube Linear Amplifier experience

VHF power amplifiers made in germany

The FL-2100Z amplifier referenced in the following images is the 6-Band model covering 10m thru 160m (no WARC bands) and not the 9-Band version that included the WARC bands. Modifications, schematics and manual

A preamplifier project based on Rainer DJ9BV project, in french

Pictures and circuit diagramm to build this power amplifier for 2 meters

An RF power amplifier, providing 7 Watts output in HF bands, schematic by ON6MU

144 and 432 Mhz GS35b High Power Amplifier

Schematic and pictures of a W7IUV preamplifier

We offer a large selection of standard and custom High Power RF and Microwave amplifiers for broadband, general communication, matched band, and personal communication markets.