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A VHF / UHF J-pole vertical antenna de ON6MU

It is very easy to create a simple 1/2 wave dipole, all you need is some lengths of wire such as the core of some mains flex or even a straightened out metal coat hanger, some co-ax cable and a connector for your scanners antenna input

This PDF document, authored by KT4QW in October 2004, details the construction and modeling of a dual-band, horizontally polarized hanging rectangular loop antenna for **10 and 17 meters**. The design, adapted from *The ARRL Handbook*, utilizes _NEC4WIN95_ software for scaling and optimization, targeting a 50 ohm feedpoint impedance. The resource includes a bill of materials, step-by-step construction instructions, and a discussion of the antenna's radiation characteristics. It presents NEC-generated elevation and azimuth patterns, comparing the loop's performance to a half-wave horizontal dipole at the same height and frequency. The 17-meter element is centered at 18.140 MHz for low SWR across the phone band, while the 10-meter element is centered at 28.500 MHz. Construction involves 14-gauge stranded copper wire and Schedule 40 PVC spreaders, with the total wire length calculated by the formula: Length in feet = 1005/MHz. The feedpoint impedance can be adjusted by modifying the rectangular aspect ratio. The document specifies hoisting the antenna to at least a half-wave above ground for testing. It notes that a balun was tested and found to have no measurable effect on SWR or radiation characteristics. A 2-meter scale model is presented to illustrate the physical design, and a "rotator" string is incorporated for directional adjustment up to 90 degrees.

Mesh constructed with enamelled wire 0.5 mm diameter For installing a support (plastic rope 2 mm) is needed. Antenna used on Solomon Isl in 1995 H44/DJ9RB

2 meter or Dual Band J-pole bicycle antenna

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.

Here is the parts list and dim. sheet for a 6m Square Copper Dipole, made from copper water pipe

The ultimate satellite Omni Antenna by Howard Sodja, W6SHP. The Lindenblad antenna consists of four half wave folded dipoles slanted 30 degrees to the horizon, oriented 90 degrees to each other in azimuth, spaced 0.3 wavelength apart

G8ODE antenna project, where the 40m & Short 80m antenna was deployed as a sloping wire antenna using the 10M fibre glass fishing pole and a hook on the house's gutter-board

a neat 1:1 50 ohm balun for use on HF horizontal wire dipoles.

M0WYM slinky dipole setup into an attic.

A potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

A slightly different 6M antenna project by N1GY, an Off center fed antenna for the 50 MHz.

This article documents an unobtrusive antenna for operation on 7MHz, primarily for contacts with stations at up to 1000Km range.

OE1MWW monopole antenna made with common RG 58 or RG 213 coaxial cable

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

The dynamics of antenna design

Why Multi-band Dipoles Need HEAVY Open Wire Line by Tom, K1JJ

The Emtech ZM-2 Antenna Tuner is a nifty little portable transmatch for QRP (low power). It utilizes the well-known Z-match circuit, which is especially useful for balanced antennas (like dipoles and loops).

The Super J Pole antenna is a co-linear vertical consisting of a number of half wave length vertical elements separated with half-wave length stubs (Tuning stub) feed with a folded matching stub by vk6ysf

A broadband travelling wave dipole for HF bands, whose VSWR is less than 2:1 from 3 to 15 MHz and does not exceed 2.6 to 1 from 2.3 to at least 30 MHz

OZ1BXM 70 MHz horizontal dipole antenna

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

Homebrewed jpole antenna for 50 mhz by IW0BZD, include pictures and schematics, in italian.

DL2HRF shortened dipole antenna for 80 meters band

Yo5ofh j-pole antenna plans for 2 and 6 meters

A portable dualband dipole robust and compact antenna usable for horizontal and vertical polarisation by ON6MU

Add some gain over your rubber dummy load with this full size dipole on your HT.

Video construction of a multiband HF trapped dipole antenna based on a variation of the classic W3DZZ design

2 meters band VHF dipole with gamma match system

Overview, summary, tutorial about the dipole antenna or dipole aerial that is widely used on its own and as the basis for other antenna designs.

The Double Bazooka Dipole is a half wave dipole with an attempt at compensation of the reactance change that occurs around resonance for a half wave dipole.

Testing and comparison of traps and trap antennas

Simple DIY stealth apartment antenna for 20m and 40m. It is basically a ZigZag quarter wave dipole antenna

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 by K5GP

A 40 ft vertical dipole antenna that can cover HF Bands from 80 to 10 meters winding a dipole in a 12m HD telescoping fiberglass pole

Windipoles is a free passive real time filter simulator. Developed under Visual Studio .NET. No software installation required. Allows design, analysis, optimizations and plots, all graphically.

Easy home brew 2 meter copper jpole antenna build - under 20 bucks - Hits repeaters 45 miles away. Parts used bought at home depot build time 1 hour.

A base station antenna you can easily build for 146,220 or 440 MHz, with performance similar to a J-pole but smaller and less obstrusive

A 144 MHz dipole antenna made from coax, PVC pipe, and aluminum foil tape

The page describes the construction of a simple omnidirectional, vertically-polarised dipole antenna for two metres using coaxial cable. It can be used indoors or outdoors, with no extravagant gain claims. The project is low-cost and can be completed in about 20 minutes.

An homebrewed dipole antenna for 14MHz

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.

A vertical antenna for the top band, made with a 26m fiberglass spiderpole by DJ0IP

Constructing a Lindenblad antenna for 137MHz NOAA satellite reception involves specific design considerations for optimal performance. The resource details the use of 4mm galvanised steel fencing wire, 300-ohm television ribbon cable, and wood/plastic components for the antenna structure. Key dimensions for a 137.58MHz-resonant antenna are provided, derived from the ARRL Satellite Handbook, specifying s, l, w, and d as 42, 926, 893, and 654mm respectively. The antenna is designed for Right Hand Circularly Polarised (RHCP) signals, requiring the four folded dipole elements to be tilted clockwise by 30 degrees. A significant aspect covered is impedance matching between the antenna's 75-ohm impedance and a typical 50-ohm receiver input. A twelfth-wave matching transformer, constructed from 117mm sections of 50-ohm RG-58 and 75-ohm RG-59 coax with a 0.66 velocity factor, is described. The article also addresses coaxial cable and connector selection, recommending 75-ohm Type-N connectors for RG-6 cable in professional setups and F56/F59 connectors for general use, while strongly advising against PL-259/SO-259 connectors for VHF. Strategies for mitigating Radio Frequency Interference (RFI) are discussed, including antenna placement to shield from local TV transmitters and the use of commercial or DIY band-pass filters, such as cavity resonators or helical notch filters, along with ferrite chokes on coaxial cables. Antenna orientation is explored, noting the Lindenblad's 'cone of silence' directly overhead and its maximized sensitivity towards the horizon. An experimental vertical tilt of 90 degrees is presented as a method to improve overhead reception and reduce interference from strong horizontal signals, particularly relevant in high RFI environments like the Siding Spring Observatory site.

Fiberglass and bamboo poles poles, pole mounts

An homemade portable vertical antenna with a trap near the mid point of the main element. The trap is made with 42mm diameter PVC pipe with 9 turns of wire on it

Building coils for a portable dipole using a novel method of winding coils with weedeater cord! By K4MMG

The idea of using a low mount dipole, enhanced with reflector wires directly beneath the dipole, on the ground, appears to be a very good approach to creating an NVI specific antenna for local HF operation.

This doubet antenna is a half wave dipole antenna easy to build, in french