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HF and VHF amplifiers homebrewed by GM3WOJ

Plans and drawings of common amateur radio antennas, like jpoles, copper cactus, super jpole, omnidirectionals and quads

Transverter for 70MHz, a project by G3XBM

Working priciple of OSJ and jpole anntennas by PY4ZBZ

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

VHF UHF Amateur radio antenna and antenna parts, accessories for homebrewers, antenna kits, tubes, antenna masts, antenna tripores, insulators, power amplifier mosfet, power splitters by I0JXX

VHF, UHF, CB antennas for marine, mobile, base, remote radio monitoring and control system

The page discusses Axial-Mode Helical Antennas, focusing on turning helical antennas over perfect ground and modeling helices in NEC-2 for optimized design. It covers topics such as high-gain performance, broadband, impedance matching, radiation pattern, feedline, balun, near field, far field, and DIY applications.

LZ2US offers 3 types amplifiers for the serious VHF/UHF amateur. These amplifiers are very robust and in use by contest groups and EME stations all over the world. Every amplifier is custom made.

Outdoor equipment and electronics - handheld, base, mobile VHF, UHF and CB radios. Uniden emergency scanners. FRS and now GMRS 2-way radios.

Helical antennas have long been popular in applications from VHF to microwaves requiring circular polarization, since they have the unique property of naturally providing circularly polarized radiation. Paul Wade W1GHZ

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

Hilberling GmbH based in Rendsburg Germany manufacturer of HF VHF Transceivers, rf power amplifiers, power combines, RF generators, power supplies, Antenna Diplexers and Triplexers

Images of VHF UHF antennas

The page is about the 144 Mhz Dirty Beacon project, a VHF beacon keyer by 9A4QV. It provides technical information, project details, and resources for amateur radio operators interested in beacon keyers. The content is useful for those looking to build or learn about VHF beacon keyers.

PA is a JAVA software package containing several programs, SW/VHF/UHF Logbook (imports format from RADIOMAN, VMT), Log conversion to HTML format, Import and export functions for RADIOMAN, CT RES files, BV QSL Labels, CSV etc. Internet DX-Cluster support, Keeps track of your worked Callsigns, Checks your worked Grid Squares per band, Databases for worked Grids and Callsigns Uses K1EA CQWW.CTY country file, Easy command line version for terminal operation Moontracking as clock, Pathloss calculation

A triband VHF Yagi antenna for 6 m, 4 m and 2 m with one feed-point by DK7ZB

A 4 yagi beam VHF antenna made with PVC easy to carry in a backpack for portable operations

List of north america beacons transmitting on vhf and uhf bands compiled by WZ1V

German antenna manufacturer for VHF UHF antennas, Quad-antennas, yagi-Antenna, LPDA-Antenna, W-Lan Antennas.

A dipole for 2m, 4m, 6m band an hamdwritten note for a homemade vhf antenna that can be tuned across the VHF band

Amateur Radio website with links to radio, IT and the Arts and a link to my Yahoo VHF-CW Reflector.

The Icom IC-746 is quite a popular HF/VHF multimode transceiver which has one shortcoming in its standard configuration when used to operate modes requiring good medium-term frequency stability.

conversion of low band VHF Philips FM-92E to 6 metres

Codec2, an open-source speech codec, targets low bit rate voice communication, specifically designed for digital radio applications operating within constrained bandwidths. The project focuses on achieving intelligible speech quality at data rates around 2400 bits per second, a critical parameter for efficient spectrum utilization in amateur radio. Its development addresses the need for robust voice transmission over channels where higher bit rate codecs would be impractical or inefficient. The resource details the technical specifications and implementation aspects of Codec2, including its underlying algorithms and performance characteristics. It provides insights into how the codec processes speech to achieve its low bit rate, outlining the various coding schemes and their impact on voice fidelity and error resilience. The information presented allows radio amateurs and developers to understand the codec's operational principles and its suitability for integration into custom digital communication systems. Applications for Codec2 extend to digital voice modes on HF and VHF bands, enabling more users to share limited spectrum resources. The project's open-source nature facilitates community contributions and widespread adoption, fostering innovation in digital amateur radio. It represents a significant effort to provide a freely available, high-performance speech coding solution for the amateur radio community.

Demonstrates the design principles and performance characteristics of **corner reflector antennas**, emphasizing their high gain and directional properties. It covers critical design factors such as the corner angle and the spacing between the radiating dipole and the reflector vertex. The resource explains how reducing the corner angle increases gain but lowers feed impedance, making matching more challenging. Practical angles of 90 degrees or 60 degrees are discussed, with 90 degrees offering easier impedance matching despite slightly lower gain. Details key design considerations, including reflector side length exceeding two wavelengths and reflector width greater than one wavelength for a half-wave radiator. It specifies reflector construction using wire netting, sheet metal, or parallel metal spines spaced less than 0.1 wavelength. The article provides a table with general dimensions for UHF and VHF bands, noting typical impedance values of 50 to 75 ohms and expected SWR of 1.7:1 on the lower band edge. Adjustable radiator-to-vertex spacing is highlighted as crucial for final tuning.

Presents a commercial entity specializing in robust portable antenna mounting solutions for amateur radio field operations. The company's primary offering, the Tilt-N-Raise system, facilitates rapid deployment and secure elevation of various HF and VHF/UHF antennas in temporary setups. These mounts are engineered to withstand environmental stressors commonly encountered during DXpeditions, contests, and emergency communications exercises. The design emphasizes ease of assembly and transport, crucial for operators frequently deploying antennas away from fixed stations. The system typically accommodates mast sections, allowing for significant antenna height, and provides a stable base for directional arrays or wire antennas. Operators utilize such mounts to optimize signal propagation and minimize setup time in diverse outdoor environments.

High End isopole VHF & UHF antennas for Amateur, Commercial and Military applications.

A project for a home made 5 element yagi-uda antenna for 2 meters, covering 144-148 MHz band by N1BMX

Specialize in servicing modern HF/VHF/UHF multimode transceivers and receivers Icom, Kenwood, Yaesu, and a few others

The Construction Principles for Duoband-Yagis 2m/70cm by DK7ZB

Modification of the MHW 612 by Motorola for the two meter band by sv1bsx

Notes on moxon antennas for VHF and HF bands. Main characteristics, gain and f/b ratio by DK7ZB

VHF & Up Software management, Station Log and maps, in English

You can make your own 2-meter "rubber duckies" that will likely perform much better than many commercial units.

136kHz portable station project by PA4VHF Dick

A homemade VHF/UHF vertical antenna made essentially with RG58 coax cable, with a 9 turns choke balun to prevent the shield acting as a RF Radiator.

Cheap UHF antenna plans for 2 meters and up including 421 1296 and 902 Mhz

Class C tuned VHF power amplifier for the 6-meter band by ON6MU

JT65 is a digital protocol intended for Amateur Radio communication with extremely weak signals. It was designed to optimize Earth-Moon-Earth (EME) contacts on the VHF bands, and conforms efficiently to the established standards and procedures for such QSOs.

Offer a wide range of homebrewing projects mainly for VHF UHF operations. From vhf antennas to preamplifiers, chargers and power supplies

IC820H or other Icom Radios Soundcard interface for VHF EME use by DF9CY

SM5BSZ article on building VHF RF amplifiers

A vertical monoband antenna design that can work from 6 meters to 70 cm by F5ZV in French

A simple VHF vertical aerial for the home station

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

Digital Voice Transceiver Project This Project began to explore the use of the DVSI AMBE 2020 voice compression chip and also the ADF7021 single chip VHF RF Transceiver from Analog Devices.

2M Yagi made from Measuing Tape by NT1K

Building a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

A VHF UHF 5+5 elements yagi antenna by CE4WJK