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This project is about a cheap way of building a colinear antenna for VHF 145MHz, and having about 10dB more gain than that little 1/4-wave magmount

QTH.COM offers a comprehensive platform for amateur radio enthusiasts to buy, sell, and trade equipment. This online service is designed to facilitate transactions between hams, allowing users to list their gear for free. Whether you're looking for HF or VHF equipment, antennas, or even vintage radios, QTH.COM serves as a hub for all your ham radio needs. The site is user-friendly and accessible, making it easy for both seasoned operators and newcomers to navigate the listings. In addition to individual sellers, QTH.COM also attracts dealers and manufacturers looking to reach a wider audience. With a diverse range of categories, including military radios and radio tubes, users can find unique items that may not be available elsewhere. The platform's commitment to providing a free service ensures that all hams can participate in the marketplace without financial barriers. Join the community at QTH.COM and discover the best deals in the ham radio world.

Rhombic Antenna dimensions for HF and VHF bands by N6JSX

SuperAntenna offer Portable, Stealth, Mobile, Base, Backpack, EmComm, Ham Radio, Marine, MARS, CAP, HF SSB, Gov, NGO and Commercial antennas

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.

Simple gain antennas for the beginner, a 2 element HF yagi antenna

The IK-STIC 2 is a vertical, all band, antenna that is over 25 feet tall yet weighs under 5 pounds. Based on a telescopic pipe or a fiberglass fishing pole, using a tuner it can easily cover the amateur radio HF bands from 40 - 10 Meters

design by Brian Williams, GW0GHF

Professional antennas in MF, VHF, UHF and SHF frequency range for military applications, civil-professional market, mobile communications, radioamateurs and antennas for special applications - EMC, radiomonitoring, etc.

NC4JB Josh explain in this article how to setup a simple and cheap indoor dipole antenna that can be used on almost all HF bands

KF4SCI picture of a project for a VHF UHF jpole antenna working on 220 and 440 MHz.

W5ALT Indoor Vertical Antenna is a base loaded vertical antenna that can be tuned on almost all HF bands by adjusting a big coil. Operating a ham radio station from an apartment in Maracaibo, Venezuela, the author demonstrates effective communication with over 100 countries using a custom-built indoor vertical antenna. Addressing common misconceptions, the design uses a balanced approach with radials and a base-loaded vertical element made from affordable materials. The antenna fits discreetly indoors, covers 6 to 40 meter bands, and achieves acceptable SWR with an MFJ tuner. Despite limited space and typical apartment challenges, the setup enables reliable DX contacts, confirmed by numerous QSL cards, proving indoor antennas can perform well in constrained environments.

The Joystick antenna was used many years ago as an all band vertical HF antenna under restricted space situations that would cover from 80 meters thru 10 meters with a tuner and was a great commercial success Some hams even had success with it on 160 meters.

A vhf moxon antenna plan

Create - Reliable antenna and antenna rotators from japan. Manufacturer of amateur radio products, HF VHF UHF antennas, antnena towers, antenna rotors, HF Log Periodic Antennas, VHF UHF wideband amateur radio antennas

VHF Antenna in a lunchbox. The magnetic loop on two metres band Lloyd Butler VK5BR

Constructing an HF End-Fed Half-Wave (EFHW) vertical antenna, the resource details the winding of a monoband matching unit, inspired by _AA5TB_, designed to provide a 50 Ohm impedance match without a ground plane or antenna tuner. It specifies the use of a _T200-2_ ferrite core for the transformer, outlining the 13-turn secondary and 2-turn primary winding process with enamelled copper wire. The document also describes the integration of a coax capacitor, whose length is critical for tuning and varies by band, with specific starting lengths provided for 20m, 17m, 15m, 12m, and 10m operation. The practical application section guides the builder through tuning the antenna using an antenna analyzer, emphasizing the iterative process of spacing secondary windings and trimming the coax capacitor to achieve resonance at the desired band frequency. It highlights the antenna's low angle of radiation, beneficial for DX, and claims up to 2 S-points improvement over a _G5RV_ or similar doublet when used as an omnidirectional vertical. A comprehensive shopping list, including specific part numbers from _Rapid Electronics_, is provided, along with advice on selecting fiberglass fishing poles for support and suitable antenna wire.

CB radios, VHF transceivers, scanners antennas and accessories

A Portable VHF-UHF Roll-up J-pole Antennam that resonates on both bands but actually performs as a half wave radiator on both bands

10 to 20 meters band log-periodic antenna project with SWR Plots, boom lenght and element spacing.

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.

Mobile antennas, loading coil current, and loaded antennas. efficiency and electrical rules. Loading inductors used in mobile HF antennas.

MQ-1 four band HF beams 20,15,10,6 meters MQ-2 six band HF beams 20,17,15,12,10,6 meters, beam antennas and Hybrid Quad antennas

manufacturer of VHF and microwave antennas and related products, from 50 MHz through 10 GHz

Buildin a VHF Jpole antenna with detailed pictures

A homemade Magnetic Loop antenna from a spare 3m length of RG213 working from 30m to 15m with a 130pF tuning capacitor

A simple and low cost multiband vertical hf antenna covering 5 bands (20m-10m) from an old CB antenna

An option for restricted and limited space, to operate the six meters band with an indoor three elements yagi antenna by Brian Williams

Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.

This is a base-loaded vertical antenna that mounts on the car's roof. The loading coil is designed as a variable inductor, with a three-legged chariot that travels up and down inside the coil, with grooved brass wheels running on the coil turns, and driven by a slotted rotor tube.

A VHF / UHF J-pole vertical antenna de ON6MU

G3YCC article pn the W3EDP end-fed antenna for 80 to 20 meters bands

Simple, inexpensive and easy to erect, this antenna provides directivity, low angle radiation and a small gain on a number of HF bands.

A VHF Quad antenna for teh two meters band in italian

A standard 6 elements design scaled for UHF application. All material used in this project are easily obtainable tubes and rods which is limited within a total budget of $18.

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.

The Buddipole is a hi-tech, take-apart dipole designed for HF portable operations. The antenna uses a multi-band adjustable coil for all bands 40m - 2m.

Elelement yagi beam antenna for 2 meters band by ON6MU

N5IW ideas to build your own antenna in a restricted lot, or a stealth antenna. Includes PPT files of HF and VHF stealth antennas.

How to build a high gain vertical antenna for the UHF amateur or CB Bands, by radio experimenters handbook

A multiband end-fed antenna that cover 3.5 to 30 Mhz using a 1:64 Balun based on a FT240-43 core

Arrow-Style VHF/UHF portable satellite antenna by VE2ZAZ

3 to 30 Mhz antenna analyzer schematic by YO3DAC / VA3IUL

Members only techical pages about Sloper antennas

A 5-band (20m-10m) HF antenna - Just 7ft square and great for a small garden. Build it yourself for around 60 GBP.

ON6MU Optimized 10 and 6 and 4 element UHF Yagi Antenna

If you are looking for an easy antenna for your favorite band, you can't go wrong with an halfwavelenght dipole, all you need is 3 insulators and some wire

146MHz 5/8 ground plane tower mounted antenna. The antenna was largely based information and analysis provided by the RSGB's. VHF UHF Manual, fourth edition by G.R.Jessop, G6JP

A javascipt online calculator for 2 and 3 element beam antennas. Just input frequency and will diplay element dimensions and spacing. Measurements in Feet and Meters by G4VWL

A Versatile Innovative Portable Multi-band Tunable Antenna can work HF VHF and UHF ideal as portable or balcony antenna