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The 4-band Fritzel model FD4 is a special version of a Windom antenna. It is a half-wave long on the lowest frequency, and is fed from a coax cable through a transformer inserted in the wire at one-third from one end

Two Wire Beverage by Jeff Parke, describes a two-wire Beverage antenna design for improved reception with switchable direction (forward/backward) and lower noise level. It includes details on building the antenna, matching transformers, and a control box for selecting direction and connecting to the receiver.

So you want to build a Beverage Antenna. This article offers insights on building a two-wire Beverage antenna for better reception. Key points include using long wire (at least a wavelength, ideally two), keeping it straight and away from vertical conductors, and sloping ends for noise reduction. The author recommends copper clad wire and mentions transformer design considerations for later discussion.

A simple multi-band magnetic loop antenna designed for 20, 30 and 40 metres, made from 16 feet of RG58 coax cable. The performance is impressive for its size but not meant to replace a Yagi. The antenna features a tuning head, matching unit, tuning capacitors, band change switch, and matching transformer. The feedpoint is at the bottom of the loop. The document provides detailed instructions on assembly and operation.

How to obtain a dual voltage without a transformer

Occasionally errors are made regarding core selection. This especially includes baluns, where on occasion some very strange ideas surface.

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

Rolling your own transformers and chokes. Rewinding salvaged power transformers, considerations and step-by-step guide

The K1FZ series of beverage antenna transformers are what you need to utilize your beverage antenna to its full potential

There are lots of good designs for matching transformers for receiving antennas. Make it yourself it's cheap and easy, and very high performance. This is the design used in the TRX-9 transformers.

Electronic kits, modules, devices and cases, transformer, boards, electronic accessories

This 1:49 transformer is used with wires any multiple of 1/2 wavelength. This is not a matching network, it's a wideband transformer and it has some advantages compared to LC matching

The design of Ruthroff broadband voltage transformers

This is a 200 Watt PEP step up transformer for end fed full and half wave antennas without radials, designed as a 200 Watt PEP

Why Beverages need good transformers by VK3APN

This application note is designed to help the reader understand how balun transformers can be used in today's RF/Microwave communication applications.

This project produces an inexpensive, multiband, end fed HF antenna matchbox, quick and easy to setup. This project creates a trifilar wound, 9:1 UNUN toroid matching transformer. Handles 100W and need an antenna tuner.

Electronic components dealer, semiconductors, switches, leds, motors, solar energy, ferrites, toroids, capacitors, batteries, jacks and plugs, microphones, meters, power supplies, speakers, transformers, wire and more

An impedance transformer (9:1) to feed a high impedance long wire (~450 ohm), down to a 50 ohm unbalanced coaxial input.

The Z Match is really a basic L Match consisting of a series capcitor and variable shunt inductor, coupled to the antenna using the RF transformer action.

How to Build a ZS6BKW Antenna, an optimised version of the popular G5RV multiband Antenna, basically a random length dipole with a 450 Ohm ladder line acting as a 1:1 transformer by VK4MDX

N6RK receive 4 square antenna with transformer coupled antennas and true hibrid combiner

A complete guide to Baluns and transformers by WK5AJL

CO2KK exposes some myths about using 75-ohm feedline with 50-ohm rigs and show how to build a cotanget transformer

In this article, the author discusses the importance of good transformers for Beverages, especially for common-mode isolation. The author recommends #43 ferrite for the transformer, and provides the turns required for different core types. The author also recommends using lower permeability ferrites for better performance at lower frequencies.

A switchable Magnetic Transformer for Transmitting for various impedances

Practical applications for end-fed antenna transformers and safe, effective grounding

This article contains the measurements for building a full wave loop using wire and length of 1/4 Wave Coax Matching Transformer

Online shop for all electronics needs. Cables, Buzzers all kind of electronic components capacitors, inductors, relays, resistors crystals transformers, hardware like knobs screws nuts and washers, opto electronics, diodes and transistors, soldering desoldering products, test equipmemt and tools

W0FMS Two-Wire Beverage (SWA) Transformer Calculator

CWS ByteMark's Baluns (Balanced to Unbalanced) and Ununs (unbalanced to unbalanced) transformers are developed jointly with Dr. Jerry Sevick, W2FMI, who is known worldwide for his work on transmission line transformers

Quality amateur radio transformers and electrical supplies

A transient analysis of an inpedance transforming device, by W9DMK, in pdf format

Transmission Line 75 ohm to 50 ohm Transformers

Practival project that contains two isolation transformers, one for AF from the tranciever to the line in on a soundcard, and one from the audio out of the soundcard back to the mic / data input of the radio. Both of which are variable inside the interface via two preset resistors.

Maker of filters, oscillators, cristals Coils, Toroidal Inductions, Solenoids, Bifilar wound Solenoids, Trifilar Solenoids and Transformers Located in Kansas City, Missouri

This is a QST Article published in January 1982 by W1FB D. Demaw and HH Beverage and is a complete review of the original article published in 1922, which updates and reivew the beverage antenna theory and developlment, explaining the antenna design of transformers and gives accurate reports on antenna general performance.

How do two-wire reversible direction Beverages work, an excellent document that explains fundamentals of beverage antennas. This article details the design and performance of a reversible beverage antenna. Leveraging orthogonality between common mode and differential mode currents on a 2-wire line, this antenna facilitates independent reception from both ends. While common mode signals arrive and are summed on a transformer's secondary for common mode reception, differential mode signals induce anti-phase currents, providing individual reception. Various measurements explore impedance, transmission loss, and F/B ratio, highlighting the antenna's effectiveness and areas for improvement. Notably, increasing the antenna's height significantly improved performance.

Manufacturer of transformers, inductors coils and chokes. Custom winding, EMI / RFI Filters, Antenna Windings on ferrite rod, Antenna Winding on phenolic. Any antenna coil designs.

W3HH wide-band wire antenna Article in French. The W3HH antenna, also known as the Terminated Folded Dipole (T2FD), is a compact, broadband antenna for amateur radio. It operates at an angle of 20 to 40 degrees and covers frequencies from 3 to 30 MHz. The antenna features a total length of one-third of the wavelength at its lowest frequency and is fed using a 1:4 BALUN transformer for impedance matching. A termination resistor around 390 Ω optimizes performance, making it suitable for various amateur radio applications while being easy to construct and install.

Custom transformers by Mr. Dahl has been designing specialty transformers and reactors for over 35 years, and has been a licensed Ham radio operator, K0BIT, since 1955.

Article about an end-fed anntenna for the 17 and 12 WARC Bands. 30 meters is not included in this project. This antenna includes a 14 windings unun impedance transformer using a FT-140-43 ferrite toroid, that should be enought for a 100W PEP.

Two different ways to create autotransformer for end fed half wave wire antennas, by using ferrite or air core.

1:49 UNUN using two stacked FT240-43 cores for end fed halfwave antenna. To match the end fed half wave antenna to the coaxial feeder, it is necessary to have a matching network or transmission line transformer.

Power transformers for electronic, toroidals,three-phases

If you ever asked if you need an Unun or a Balun this article is for you. The right question should be do I need a feed line choke or an impedance transformer whose output is configured as balanced or as unbalanced. An impedance transformer can be configured as a voltage transformer or as a current transformer.

Some technical information for on Opto Isolation, Transformer Isolation, Surge Protection

Use these Variac auto transformers for specific application requirements that include, but are not limited to, home coffee roasting, tube amps, and more.

This Guide helps you to build the 1:2 BalUn 600 Watts DIY kit step by step. If a delta-loop or quad-loop antenna is powered with a coax cable from the transceiver it is necessary to use a 1:2 BalUn. This 1:2 BalUn uses a symmetrical 1:2 impedance transformer.

Maker of small and compact multiband QRP UltraLight Magnetic Loop Antennas and UnUn transformer for end-fed multiband antennas