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May be of interest to anyone wishing to get on 80M (3.5MHz) that have limited space available.

Portable, and shortened with loading coils rotatable dipoles for 6 meters, 20 meters and multibands.

GM4JMU shortened dipole for 40 meters band. This article illustrates in detail how to build a resonant antenna for 7.030 MHz. Cut two 10.25-meter pieces of insulated wire, wind 40 turns of wire onto plastic tubing, and connect the wire to a central insulator using a choke balun built of RG174AU coax and a ferrite toroid. Once built, the antenna is adjusted by altering the wire length to produce the lowest Standing Wave Ratio (SWR) for best performance. The guide emphasizes careful building and adjustment for the best results.

A short but efficient dipole for 40 meters band

The best antenna is the simple Dipole. If you have height, you even can put up a quarter wave vertical or an inverted, but sometimes you may need shorten version by 4S7NR

Short dipole antenna for 40 meter ham band. Can be put up in the space required for a 20 meter dipole.

All antennas for shortwave broadcasting, Log-periodic, Dipole Arrays, Curtains antennas, rhombics, broadband dipoles with photos and details.

Drawings and short descriptio in spanish for dipoles and bazooka antenna.

What is NVIS Near Vertical Incident Skywave. This article on NVIS (Near Vertical Incidence Skywave) explores its role in short-range HF communication, covering 0-200 miles. NVIS utilizes antennas with high radiation angles and frequencies below the ionospheric critical frequency to achieve reliable local contact. He details optimal antennas, like low dipoles, and practical tips for maximizing NVIS performance, emphasizing its advantages such as reduced noise and independent operation without repeaters. However, challenges include frequency sensitivity and the need for appropriate antenna setups at both ends for effective communication.

Full size or shortened dipoles, Single band or Multi band, Half Square Antennas, Fan Dipole Antennas, Delta Loop Antennas, Antennas completely assembled Loading coil packages, delta loops

The Cedevita-20 is a hybrid monoband antenna, the result of merging the radiator of a shortened vertical with one element of a dipole. It fits on most balconies and must be hung from the ceiling. By ik1zyw Paolo Cravero

The K4VX linear-loaded dipole for 7 MHz, simple and practical way to make a short but efficient 40-meter dipole.

Shortened dipole with traps for 40 meters band in portuguese

A shorten Dual-Band Dipole with overall length of about 11 m. For this antenna traps are substituted by inductors, in order to cover the 10 & 40 m. Bands.

DL2HRF shortened dipole antenna for 80 meters band

Design your owm HF shiortened dipole. Includes a diagram of a lumped-constant loaded dipole antenna that is intended to fit in available space, rather than requiring a full 1/2 wavelength, at a specified frequency

An analysis of the cebik dipole and other small limited space dipoles fed with open wire ladder line.

Ham Radio 20 / 40 meter short Coax Trap dipole antenna designed with the coax trap design calculator program

Here is a very simple and practical way to make a short but efficient 40-meter dipole. The K4VX Linear-Loaded Dipole for 7 MHz

A shortened dipole for 40 meters band by Martin E. Meserve

An inverted V antenna for 40-80 with loading coils. This antenna is a full size on 40 and a shortened 80 by KG0ZZ.

A shortened 7 MHz Dipole antenna as described by Ken GM4JMU in Sprat 74.

An easy to build multiband trapped dipole that can work well on short low bands for skip contacts

The Linear-Loaded "Crappie" 40M Rotatable Dipole A Short 40 Antenna You Can Build for $50 or Less by VA7ST VE7ASK

Bobtails are vertical arrays that look like the letter "E" turned 90° clockwise onto its tails. They have 3 quarter wave vertical elements and are one wavelength long. The Half Square is a shortened Bobtail- it has 2 quarter wave vertical elements and is a half wave long.

A very short dipole with a good radiation efficiently plus a respectable bandwidth by S. C. Chuck Smith, WA7RAI

A short dipole wire antenna for 40 meters band. It is a folded dipole that do not make use of coils and can be used either in horizontal or inverted V configuration

The GM4JMU Shortened 7Mhz Dipole

This short dipole antenna has been described by Nadisha, 4S7NR and may be of interest to anyone wishing to get on 80M (3.5MHz) that have limited space available.

Build an effective dipole antenna that needs much less space by adding two loading coils. This online calculator tells you how.

The antenna build into this project is made from 2 fishing poles on a fiberglass pole in the center.

A page in french dedicated to the double bazooka antenna, with a short history of this antenna model and main characteristics including a comparison versus the dipole antenna and formulas to determine elements size.

A three band short Vee antenna is feasible with two legs per side on a dipole. 10-15-20 meters by W8HDU

A shortened multiband dipole antenna by PA0FRI in Dutch

Electrically shortened dipole antennas, article by Mark Connelly, WA1ION

An antenna for shortwave radio broadcasting consisting of rows and columns of dipoles, is a high gain directional antenna, designed for medium and long range communications.

Demonstrating the construction of a short dipole antenna tailored for the 60 meter band, this resource provides detailed instructions for radio enthusiasts with limited space. The design incorporates inductive loading using two inductors (L1/L2) made from PVC tubes, allowing for effective operation on 5 MHz. The antenna consists of 12 meters of wire, divided into four sections, with specific dimensions and materials outlined for optimal performance. Results from users indicate that this antenna can significantly enhance DXing capabilities on the 60 meter band. Feedback from operators suggests that while the design is effective, adjustments may be necessary based on individual setups, such as coil diameter and wire gauge. Many users report successful construction and operation, with some experimenting with variations to improve resonance. The practical application of this antenna design has led to successful contacts and improved signal quality, making it a popular choice among 60 meter band operators.

A small dipole antenna installed inside a balcony. This linear loaded short dipole antenna has been designed at first for the 21 MHz and then adapted for the 20 meters band.

A very popular method of making a short dipoles resonate at a given frequency. This type of antenna is suitable for single band, narrow bandwidth use.

Multiband Trap Dipole, portable short antennas, accessories and kits by DG1DBM

Complete collection of the four main parts of this excellet research on modelling and designing half wave dipole antennas for 40 meters band, covering all aspects beginning from full wave length antennas, to shortened, loaded and reshaped dipoles

An antenna for 80 meters band for those who does not have enough space to setup a halwave wire dipole that is aprox 130ft or 40 meters. The antenna is an open-wire-fed shortened dipole

Experimenting a 20 40 meter short coil loaded dipole antenna with the goal to keep the total length under 40 feet so that the dipole can be mounted on two 20 foot fiberglass pole to make a 20/40 meter rotatable dipole.

Roach pole vertical antenna for 40 and 30 meters band featuring good performance on short skips contacts compared to wire dipole

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

Free ham radio utilities written in LabVIEW includes Open Wire Calculator, Dipole Peak/Null Angle Calculator, a Coil-Shortened Antenna Calculator ad interesting Round Coil Inductance Calculator and a Skyloop Antenna Calculator

A rotary dipole antenna for 30 meters band. Each arm is about 12.5 ft and is constructed from telescoping fibreglass flag/fishing poles and short lengths of aluminium tubing. Two short lengths of glass-fibre rod were used to insulate the arms from the supporting hardware.

This is a short version, the final of the article describing how to build the Weather satellite 137 MHz horizontal V-dipole antenna.

There are several ways to reduce the length of a dipole and still use it as an effective antenna. Remember it is the electrical length that determines resonance. The physical length can be considerably less than a half wave length on your desired frequency as determined by 468/f MHz.

This antenna just requires about 24m of free space instead of 41m that a normal half wave 80m antenna needs to hang up. The so called loaded dipole uses a coil in every dipole arm to electrically lengthen the mechanical too short dipole arms. Every coil has an inductivity of 120 microHenry.