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Schematics plans by K9GDT and all infos to build a 600 Watt HF Amplifier. The amplifier uses four Motorola MRF150 50 volt TMOS power FETs configured in push-pull/parallel and biased for class AB linear operation.

The website https://www.qsl.net/dl5dbm showcases homebrew projects related to KW, 2-meter, 6-meter, antennas, amplifiers, preamps, power supplies, and more. It provides information and resources for radio amateurs interested in DIY projects and experimentation.

Use 4CX10000D / 8171, RF output power of 11 KW in key-down carrier on all bands. Power was measured with a Bird 4712 wattmeter and a 25 KW slug

A 20 ampere and more 13,8V power supply for RTX

Amateur Contact Log (AC Log) by N3FJP is a commercial Windows-based general logging program designed for amateur radio operators, supporting Windows 7 through 11. It provides comprehensive tracking for various operating awards, including Worked All States (WAS), Worked All Counties, Worked All Countries (WAC), DXCC, VUCC, Grids, Zones, IOTAs, and Lighthouses. The software features a customizable user interface, allowing operators to display specific data fields and adjust font sizes. It includes built-in databases for counties and countries, facilitates queries by band, mode, or power level, and offers a bearing and distance calculator for DX contacts. AC Log also provides DX spotting via Telnet or packet TNC, supports keyboard CW, and can play wave files. The program offers full support for ADIF import and export, enabling seamless integration with external services like eQSL, QRZ, Club Log, and the ARRL's Logbook of the World (LoTW) for QSO uploads and confirmation downloads. It interfaces with popular transceivers from Elecraft, Icom, Kenwood, Ten Tec, and Yaesu, and connects with digital mode software such as WSJT-X, Fldigi, and JTAlert via API. AC Log includes a Net Manager form for group logging, prints basic QSL label strips, and integrates with QRZ and Ham Call lookup services. The software is fully networkable for multi-PC operation, supports Parks on the Air (POTA) logging, and displays worked entities and DX spots on a real-time world map. Full featured Trial version available for 45 days

3 elements VHF Yagi homebrew antenna designed with YAGIMAX 3. Maximum forward GAIN is about 8,17 DBi. This antenna offering an effective radiation power 4 times greater of the transceiver output by SV1BSX

13.8 V 15A from a PC power supply

This sketch will read RF power and SWR from any SWR bridge, designed to work on VHF UHF bands

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.

Two types of home-brewed 12/20 Ampere 13,8volt power supplies, including detailed part lists by ON6MU

A 13,8v/5Amp 78H05 based power supply for portable use. In this example used to power up a Yaesu FT-817

Dchematics and photos of a secure power supply (short-cut, Rf feedback, high voltage etc.) by iz7ath

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

Over 40 years of experience inform the reviews and commentary presented on Dave's Radio Receiver Page, covering a wide array of radio receivers and transceivers. The resource details specific models such as the **ICOM IC-R8600** SDR Communications Receiver, which is lauded as Icom's best wide-band receiver, even surpassing the IC-R9500 in performance. Other notable reviews include the ICOM IC-7300 HF Transceiver, highlighting its direct sampling SDR technology and spectrum scope capabilities, alongside numerous models from Japan Radio Co. (JRC), Kenwood, Yaesu, and various portable shortwave receivers. The content provides practical insights into the performance and characteristics of each radio, often drawing comparisons between models. For instance, the early issues with the AOR AR7030 receiver's Bourns mechanical encoders are thoroughly documented, including AOR's eventual switch to higher-quality Alps encoders. The page also features reviews of antennas like the MFJ-1026 Noise Canceling Signal Enhancer and various power supplies, offering a holistic view of radio monitoring setups. The author's "2 ear / 2 eye method" emphasizes real-world listening experiences over laboratory measurements, providing a unique perspective on equipment utility.

This is a C-L-C type tuner with a reflected power indicator. Tuning is done for minimum reflected power.

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

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.

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

The homemade CW paddle key design, inspired by a QRP homepage, utilizes soldered PC board material for its construction. The builder, DL5NEJ, modified an existing design to achieve a smaller footprint, preferring a compact setup for portable operations. This paddle was specifically built to complement a Wilderness Radio SST20 QRP transceiver kit, demonstrating its suitability for low-power operations. The project details suggest a straightforward assembly process, with the primary components being readily available PC board scraps. The design emphasizes simplicity and functionality, aiming to provide a reliable keying experience comparable to commercial paddles like the Bencher. Performance evaluations indicated the simple paddle operates effectively, prompting further exploration into similarly minimalist QRP rig designs. Additional construction details for a similar paddle are available from PA0CMU.

This little gadget is that it allows you to tune up at full peak output power, whilst limiting the average power to a fraction of the peak, thereby protecting the PA from meltdown

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

Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.

80m hexfet power amplifier by W7ZOI

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

20/22 Ampere or 30/32 Ampere 13.8 volts power supply RE-PSF14A20 or PSF14A30 by ON6MU

144 and 432 Mhz GS35b High Power Amplifier

Managing extensive amateur radio contact logs efficiently requires specialized software that integrates various operational aspects. Aether provides a macOS-native logging solution, designed from the ground up using Apple's Cocoa, to streamline QSO entry, organization, and retrieval for Mac users. It supports modern macOS technologies and offers an intuitive interface, aligning with the user experience expected on Apple platforms. The application includes features such as automatic dupe checking, which quickly identifies previous contacts with a station, and awards tracking, indicating if a new contact is needed for specific operating awards. Aether also integrates rig control via RS-232, automatically populating frequency, mode, and power data from supported Elecraft, Icom, Kenwood, Yaesu, and some TEN-TEC transceivers. This automation reduces manual entry errors and speeds up the logging process. Furthermore, Aether offers comprehensive QSL management, including synchronization with eQSL.cc and Logbook of The World, and the ability to print QSO detail and address labels for paper QSLs. It also incorporates automatic callbook lookup from sources like QRZ.com and HamQTH.com, and calculates distance and beam heading, with Google Maps integration for visualizing contact locations. Full ADIF and Cabrillo import/export capabilities ensure compatibility with other logging software and contest submission platforms.

VU2RAR basic VHF power amplifier suitable for 144-146 Mhz output power can vary from 3 to 25 Watts.

A table with Loss in DB/100m , Max power in Watts, Diameter in mm , Velocity factor (VF) expecially in VHF UHF and Microwave

G3WZT design for a single stage bi-polar 100-150W Linear Power Amplifier for the 6M band.

1.2-30V 1.5A variable regulated power supply

Demonstrates the construction of two distinct wideband RF preamplifiers, detailing their component requirements and performance characteristics. The first design leverages monolithic microwave integrated circuits (MMICs) such as the MAR-6, MAR-8, or PGA103, offering a broad frequency response from DC to 2 GHz with a gain of 22.5 dB at 100 MHz and a noise figure typically below 3 dB. This MMIC-based amplifier incorporates protection against power supply transients and features a 50 Ohm input/output impedance, operating from an 8-20 volt supply with low current drain. The second preamplifier design utilizes a BSX-20 transistor, providing amplification across the 14 MHz to 550 MHz range. This simpler, more economical build achieves an average gain of 12 dB at 145 MHz and a noise figure of approximately 1.1 dB. It operates from a 7-15 volt battery supply with a current draw of 6 mA. Both projects emphasize critical construction techniques, such as maintaining short RF connections, ensuring 50 Ohm impedance paths, and mounting the circuit within a shielded enclosure to optimize performance and minimize noise. The resource also discusses phantom power options for antenna-mounted preamplifiers and precautions for use with transceivers, including output protection diodes and static bleeders.

An RF power supply for 144 MHz schematics and instructions

High Voltage Supply for GS 35B Amplifier

RF power meter, dummy load, project

Low power VHF RF amplifier with VMP1 Mosfet by IZ1BTS IK1XPD

1 watt amplifier for 10 ghz made from surplus stuff

This low power transmitter is developed for ARDF exercising purposes but of course can be used as super QRP transmitter either. With 1 or 2 meter wire as antenna and a ARDF receiver with ferrite-rod antenna the range is about 100m but with better antennas and a 'real' receiver the range is probably much larger.

VU3NSH article on high current universal supply for rigs

Computes the Standing Wave Ratio, given the power readings on a line.

A VHF power amplifier made with two cheap RF transistors, 2N3924 as driver and a BFS22A for final stage, giving an unexpected output power of 7-8 watts maximum

A MRF141G 3-175MHz Broadband Power Amplifier DL4MEA 02/1998

Home made RF power amplifier for six meter band

The 11-meter band, often associated with Citizens Band (CB) radio, presents unique challenges and opportunities for long-distance communication, particularly for operators interested in DXing. This group facilitates discussions and information exchange among enthusiasts who operate on this frequency, often utilizing single-sideband (SSB) modulation for improved range and signal clarity compared to traditional AM CB operations. The community provides a platform for members to share experiences, technical insights, and propagation reports relevant to 27 MHz operations. Members engage in discussions covering various aspects of 11-meter DX, including antenna configurations, transceiver modifications, and operating techniques to maximize signal propagation across continents. The forum serves as a central hub for coordinating contacts, sharing QSL information, and celebrating successful long-haul QSOs. Specific topics often include optimizing power output, reducing noise, and understanding solar cycle effects on 27 MHz. The group's activities extend to organizing virtual gatherings and promoting ethical operating practices within the 11-meter DX community. It supports both seasoned operators and those new to the band, fostering a collaborative environment for exploring the capabilities of CB radio beyond local communications.

Schematic of a regulated 0-24v 2A Power Supply

Two types of multi-functional Home-brew 6/8Amps - 20 Ampere variable power supplies by ON6MU

Circuit diagrams drake tr7, Schaltbilder Drake Tr7, antenna tuners, baluns, and home brew power supplies, dual tone ssb test generator, zweiton ssb test generator, zweiton testgenerator, dual tone test generator by DK4DDS

G3WZT design for a bi-polar 600W Linear Power Amplifier for the 6M band.