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Cannot find the inductors you need for an antenna, a tuner or amplifier ? Build your own it is easy!

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

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.

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

An RF power supply for 144 MHz schematics and instructions

This tutorial will set out the design stages required to design a theoretical microwave amplifier

A pdf file with schematics of an ssb and cw filter AF amplifier

Amplifier keying buffer for ICOM radios & others. Suitable for IC-746 IC-756 PRO and PROII. ACC1 key interface by KK5DR

Whether we are tuning up homebrew equipment, checking antenna VSWR, adjusting a linear amplifier, or just monitoring output power during a contest, almost all aspects of ham operation can use a power meter. Paul Wade W1GHZ

Converting a ZETAGI B303 power amplifier for 50 MHz usage

RF and Microwave Power Amplifier and Transmitter Technologies, amplifierlinearity, efficiency and available RF power devices.

2 x GI7B in push-pull 2m and 6m 1kW Power amplifier from PA0ZH

Ebook by Akira Matsuzawa Tokyo Institute of Technology, Building blocks in RF system and basic performances, Device characteristics in RF application , Low noise amplifier design, Mixer design and Oscillator design

6-Meter Solid-State 100W Linear Amplifier complete documentation German and English

A rebuild job on a Heathkit SB-200 amplifier by N4NAB

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

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.

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

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

Icom PW1 Linear Amplifier, setup and configuration PDF file

Article appeared on 10/05 issue of QEX about the impact of load SWR on the efficiency of Power Amplifiers, PDF File by K9LA