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HF UHF/VHFAntennas, dipoles, accessories and rotators

Attic Fan dipole antenna that allow to operate QRP from 40 metres to 10 metres, specifically 40, 20, 17, 15 & 10 meter band

Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.

How to create a simple but effective half wave dipole, illustrated instrucions on how to build wire antennas

How to build a multi-band dipole antenna with a single coax feed. Instructions for a 160M antenna that will fit in the space that a 75M dipole will with almost as good of results as a full size 160M dipole.

The Fan dipole antenna offer a easy to setup and efficient HF multiband antenna that does not require tuners or antenna switches, diagram by YC8PVU.

A three-frequency multi-band dipole that can be extended easily to additional bands. This article includes a multiband fan-dipole antenna for 80-40-20-10 meter band.

This is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It is a dipole fed off center with a 4:1 current balun at the offset feedpoint. The antenna shown covers 80, 40, 20 and 10 meters with 15 meters and WARC bands

Homebrew a cobwebb antenna for the HF bands. This page describe a cobwebb multiband antenna resonating on 14 18 21 24 and 28 MHz. The cobweb antenna model can be considered a fan dipole, or better, multiple dipoles fed in parallel.

Ham radio antennas and electronics, specialized in 1/2 wave dipole, OCF dipole, windom, full wave loop, end fed, inverted L, portable end fed antenna, long wire, SWL antenna, fan dipole, multiband dipole, G5RV and military antennas.

Extension to an existing fan dipole originally modeled for 40 20 and 6 meters. This modification will add 80 15 and 10 meter bands.

The Fence Fan Dipole a quick, easy and inexpensive multiband dipole antenna

Interesting article on multiband fan dipoles. This article give an overview on designing this wire antenna, and planning a robust installation and proper feed line. Includes notes on setting up a commercial fan dipole antenna and on how diy your own.

40/20/10 Meter Fan Dipole attic antenna article by KD2GOE

Operating an 80/40/20M fan dipole for DX is analyzed through EZNEC modeling, focusing on the antenna's performance in a real-world, low-height installation. The resource details the physical construction and SWR measurements of the fan dipole, comparing them against EZNEC simulations. It also incorporates High Frequency Terrain Analysis (HFTA) data to illustrate typical DX elevation angles for various regions from New England, providing a crucial context for evaluating antenna patterns. The analysis presents EZNEC-generated azimuth and elevation patterns for each band (80M, 40M, 20M) at specific frequencies, showing gain figures at different elevation angles relevant to DX propagation. It compares the modeled SWR with measured SWR, attributing discrepancies to coax attenuation. The study concludes with observations on the antenna's azimuth performance (omnidirectional within ±1.5 dB) and its less optimal elevation gain at desired DX angles, highlighting the impact of low antenna height on DX capabilities.

Experiments on HF antennas for restricted spaces. In this article author experiments antennas for 80-10 meters band having just a very small garden and several restrictions. Basic antennas consists of laded multiband dipoles and fan dipole antennas

An homemade fan dipole antenna for 20 30 40 meter bands, setup in a 15 meter wide garden. The longest leg for 40 meter is folded to fit in the 7.5 m

Presentation by AC8GY on classic G5RV Antennas and other horizontal dipoles, the popular G5RV, ZS6BKW, dipole fan, Alpha-Delta DX-CC and a trap dipole are modeled in EZNEC and compared.

A comparison of multiband dipoles, including jumpered dipole versus fan dipole antennas, dipole fed by ladder line, resonant dipoles antennas. ARRL lab notes

The fan dipole antenna as an alternative to the paralled dipole antenna, to achieve a larger bandwidth and a better tuning by decreasing elenment influences.A project based on the W6HDG original concept.

Amateur Radio 40m 20m 15m Half Wave Fan dipole antenna project with part list, pictures and drawing. Includes the option to expand the antenna to cover the 80 meters band

There are a large number of antenna designs for HF. One choice out of many is the fan dipole. The ability to transmit of multiple bands without needing a tuner (and even more with a tuner) is a very desirable factor in choosing a versitle antenna for HF.

An interesting presentation of a real multiband Fan Dipole antenna, optimized for better DX operation performances, considering the terrain, position, DX destination path and other influencing factors

How to build Fan-Dipoles by DK7ZB. Experiences with various band combinations. Not all combinations are working properly. If the frequencies are to close together the impedances will lead to a very bad SWR. This happens with the bands 10-12-15m or 15-17-20m.

The antenna in this project is a modification of the techniques used to design a multiband fan type dipole with little or no tuning involved having a total space of 105 feet

A fand dipole antenna home made for the 7,14,50 MHz. This article descbribes how to homebrew the antenna, hot to setup and some SWR measurements.

This PDF guide provides detailed instructions and diagrams for constructing a fan dipole antenna, a popular choice among hams for multiband operations. The guide covers the design, materials needed, and installation process, offering step-by-step guidance to help hams set up an effective antenna system for their radio operations.

An attic wire antenna with several modifications during the time. Began as a simple coax fed doublet antenna, and upgraded to a multi-band hf fan dipole, till the G5RV all deployed in an attic.