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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

German article on the multiband dipole by DG0KW. This antenna can be configured for several bands and can work in 3 or 4 bands mode. Can be used in restricted space lots.

This resource details the computer-optimized design of the _ZS6BKW_ multiband dipole, an evolution of the classic _G5RV_ antenna. It begins by referencing the original 1958 RSGB Bulletin article by Louis Varney G5RV, explaining the operational principles of the G5RV's flat-top and open-wire feedline on 20m and 40m, noting its impedance transformation characteristics for valve amplifiers of that era. The article then transitions to the rationale for optimizing the design for contemporary solid-state transceivers requiring a 50 Ohm match. The core of the project involves using computer modeling to determine optimal lengths for the flat-top and matching section, aiming for a VSWR of less than 2:1 on multiple HF bands. It discusses the process of calculating feedpoint impedance based on antenna length and frequency, referencing professional literature from Professor R.W.P. King at Harvard University. The analysis also considers the characteristic impedance (Z(O)) of the open-wire line, identifying a broad peak of adequate values between 275 and 400 Ohms. Specific design parameters for the improved ZS6BKW are presented, including a shorter flat-top and a longer matching section compared to the original G5RV, with a velocity factor of 0.85 for the 300 Ohm tape. The article confirms acceptable matches on 7, 14, 18, 24, and 28 MHz bands when erected horizontally at 13m, and also discusses performance in an inverted-V configuration, noting frequency shifts. The author, Brian Austin ZS6BKW, emphasizes the antenna's suitability for modern 50 Ohm coaxial cable without a balun.

JJ0DRC's HF multi-band delta loop antenna project, initially conceived during the waning peak of Cycle 23, addresses the common challenge of achieving effective DX operation from a small residential lot in Japan. Dissatisfied with a ground plane antenna's performance in SSB pile-ups, the author sought a beam-like solution without a tower, drawing inspiration from a JJ1VKL article in CQ Ham Radio Sep. 2000. The antenna, constructed in October 2000, employs two 7.2-meter fishing rods (37% carbon fiber, reinforced with cyano-acrylate glue and aluminum tape) and 1mm enameled wire, fed by an Icom AH-4 external antenna tuner. While the exact beam pattern remains unmeasured, JJ0DRC observed a significantly higher callback rate compared to dipole antennas, particularly on higher bands. The system's circumference length of 15-20m is crucial for maintaining a good beam pattern across HF bands, though performance on lower bands like 80m, 40m, and 30m becomes less directional as the length deviates from a full wavelength. Ongoing maintenance addressed degradation issues, including aluminum tape cracking and wire breakage at connection points due to strong winds (often exceeding 10-15m/s in winter). The author reinforced rod connections with IRECTOR PIPE SYSTEM components and INSU-ROCK ties, and improved wire attachment methods using Cremona rope and epoxy bond to enhance durability.

The I0JXX is an italian company that offers market their projects, also sells electronic products of high quality, both for Ham, both Broadcast and their accessories. VHF Antennas, mosfet power amplifiers, filters, insulators, power dividers, telescopic poles, antenna masts

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

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.

Build yourself a postage stamp 40 meter wire dipole antenna that fits in a space a little over 20 wide and works reasonably well at low heights

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

A multi-band inverted-V dipole for portable operation by GM3VLB

A 40 80 dipole antenna design by WA6ESC PDF File

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

Located in France, DXBeam designs and manufactures a range of monoband, dual band and triband antennas, rotary dipoles, Moxons and Yagis

This article explores a theoretical model for the losses of an 80m / 40m trapped inverted V dipole antenna system using a bootstrap coax trap, but does not examine the pattern of the antenna.

J-Pole Antenna by K4TAX

A simple, cheap, efficient tv antenna that you can make yourself.

Hints about Jpole Yagi and Quad antennas

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

Pictures of a 2 meter, 220, 440 copper J-Pole antennas

Put up the longest dipole you can fit, feed it with open wire line, connect it to the balanced output of your tuner and poof! Instant multiband antenna. Is life really that simple?

Online calculator and construction instructions

D3+ High Performance Antennas for Field Day. This article describes versatile broadband wire antennas. These antennas will double your effective radiated power over a dipole, will be easy and inexpensive to build and install, and will be simple to match.

A multiband 20/40/75/160 trap dipole antenna plan by KG0WX

Antenna manufacturer from Poland, produce dipole wire antennas, W3DZZ FD4 Windom and long wires, baluns, dealer for toroids and connectors managed by Leszek Mlynarczyk SP1BKS

A W3DZZ trapped dipole for 80 40 and 20 meters band by ZL1BJQ

An easy to build single wire antenna for 160 and 80 meters with a better than 2 to 1 swr across the 80 meter band

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.

A french document about Inverted V dipole antennas

The ZS6BKW wire antenna, a variant of the G5RV, utilizes a specific 13m (42.6 ft) length of 450-ohm window line as its matching section, feeding a 28.5m (93.5 ft) flat-top element. This design aims for lower SWR on 40m, 20m, 17m, 12m, and 10m compared to a standard G5RV, often achieving SWR values below 1.5:1 on these bands without an antenna tuner. The feedpoint impedance transformation provided by the window line allows for direct connection to 50-ohm coax on multiple bands. F4FHH's experience involved constructing the ZS6BKW and evaluating its performance against an _OCF dipole_ (Off-Center Fed) on various HF frequencies. The article includes observations on SWR readings and operational effectiveness, highlighting the ZS6BKW's suitability for multi-band operation. The antenna's overall length, including the flat-top and window line, is approximately **41.5 meters** (136 feet), making it a significant wire antenna for fixed station use. Comparative analysis with the OCF dipole provided practical insights into the ZS6BKW's advantages and limitations, particularly concerning bandwidth and tuner requirements.

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

An home made trapped dipole antenna for 40 and 60 meters band by 2E0HTS

A rotateable dipole specifically for the 20m based on W3FF Buddipole design by ZR6KMD

The simple dipole is perhaps the best antenna for consistent performance. Basic page on dipoles by G3PTO

This article describes the design of an antenna for local contacts on 7MHz, including a simple and efficient matching system that presents a 50 ohm load to the transceiver.

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

Homebrew project of a dipole for six meters band by KK5ID

Multiband and monoband HF Vertical antennas and rotatable dipoles manufacturer based in Texas USA

A telescopic pole that you adjust to suit the band you're working on , tested on 40 20 and 15 meters band by M0PZT

The half wave dipole antenna is a simple and practical antenna model that consists of a half wavelength long centre fed conductor.

A simple beam antenna offering good performances on 3 bands by 9m2mso

The QRP choke balun described utilizes a high permeability ferrite rod and RG-174 coax, aiming to present high impedance to common-mode currents across the HF spectrum. The construction involves winding as many turns of RG-174 as possible around the ferrite rod, then encapsulating the assembly with hot glue. This design prioritizes maximizing inductance to suppress unwanted shield currents, particularly in unbalanced antenna configurations. While the balun's effectiveness is subjectively reported as good, a potential design consideration involves the dielectric properties of the hot glue. This material could increase turn-to-turn capacitance, potentially reducing the balun's performance at higher HF frequencies, though this specific aspect has not been formally tested by the author, _AA5TB_. The project serves as an illustrative example of a practical, junk-box construction rather than a rigorously engineered solution. Photographs detail the evolution of the balun, from the initial winding process to its integration within a _B&W dipole center insulator_ and final camouflaged assembly.

The SQUARE-Pole is a 1/2-wave dipole that has been bent into a square by WB2VUO

Dual band vhf uhf dipole antenna by DL7JV

J-pole antenna made easy using a twinlead by W4ZT

Different band dipoles can be put together with a single feed, learn how by W8HDU

The Classic Multiband Dipole Antenna QST article. The open-wire feed line dipole antenna is easy to install and offers surprising performance on several bands. You can install it in almost any configuration; it does not have to be strung in the traditional horizontal flat top

40 meter vertical antenna construction, a shortened easy-to-build vertical, with no-radials, made from surplus military camouflage poles

A vertical dipole for 10, 15, 20 and 40 meters made adapting two Hustler Model 6-BTV antennas by w6sdo