Search results

Loop Antenna Starter Kit contains detailed plans for building the MTM Scientific, Inc. loop antenna from scratch.

A delta loop antenna for 17 meters band include eznec antenna model file

Launching a balloon or kite supported tall vertical or protracted inverted L.

ARRL index of document about trapped antennas and notes on traps usage

This page describes a simple way to determine the main RF characteristics of a Wifi (IEEE802.11b/g wireless LAN) antenna.

A compact Beam Antenna That Can Be Built At Home. Made with lightweight wooden "X" frame with two folded and linear loaded wire elements. The two elements are approximately a half-wave each.

Article on rhombic antennas, radiaton patterns, disvantages, and more info on rhombic aerials

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

Presents the design and construction of the OK2FJ Bigatas, a portable, automatically tuned vertical antenna covering 80 through 10 meters. It details two distinct control systems: one utilizing BCD band data from Yaesu FT-857/897 transceivers, and another employing voltage level sensing for the Yaesu FT-817. The resource provides specific instructions for building the antenna's radiating element, loading coil with switchable taps, and the control circuitry, emphasizing the use of readily available components. The article outlines the physical construction of the antenna, including the use of duralumin tubes for the radiator and a PVC tube for the coil form. It specifies coil winding details, tap points, and the integration of radial wires for ground plane operation. The control electronics section provides schematics and component lists for both the BCD decoder (using a 74LS42 IC) and the voltage comparator (using an _LM3914_ bargraph driver), enabling rapid, automatic band switching without the minute-long tuning delays common in other systems. Crucially, the antenna achieves rapid band changes, with typical SWR values centered on common operating segments, such as **3.7 MHz** for 80m SSB. It also discusses modifications for CW operation on 80m and the trade-offs between antenna efficiency and full-range automatic tuning on higher HF bands, where manual adjustment of radiator length is suggested for optimal performance on 15m, 12m, and 10m. The resource includes construction photos and a discussion of cable requirements for reliable operation.

A simple base loaded quarter wave vertical, which can be used on a car or portable by G3YCC

Presented here is a high-performance, circularly polarized omni-directional antenna that is easy to build, easy to tune, inexpensive, and will work all the mode J Low Earth Orbit (LEO) satellites

Built around a 1/2" pvc frame, Larry's 6 meter moxon antenna is made from #8 aluminum ground wire

Double bazooka antennas

Easy Quad calculator, enter center frequency to get a quad antenna size

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.

This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

Improved Helical Antenna Design for 802.11b WLAN by PA0HOO

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.

Build your own home made Antenna Analyzer with an arduino micro, or a cheeper one with a pic processor

Overview, summary, tutorial about the log periodic antenna or aerial used for wideband RF antenna applications

F6CHT plan for a multiband yagi antenna that covers 6 to 30 meters band in french

W5JGV antenna tuner for 150 - 500 Khz band

Simple implementation of the ARRL Antenna Book design equations for the axial-mode helical antenna.

Remote Control Antenna Switch made with two circuits board

A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

Vortex Antenna Systems, radio communication antenna aanufacturer and supplier of antenna related hardware. Ham radio HF and VHF Antennas, antenna parts, mast and mounts.

Solution to your OEM needs and can meet your design or vended antenna requirements for antennas from 400MHz to 10 GHz.

A 2-way remotely operated HF antenna switch, based on an idea supplied by G3YEU

A very simple Eh antenna for 11 meter, drawings in english and italian.

Tombone VHF antenna for 146 MHz ad designed by YB8EIP

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

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

A very compact receive antenna made with ferrite bars by PA0FBK

Rhombic antenna for shortwave radio broadcasting, general description and radiation patterns

K6SGH introduce the hamloop antenna L7 series

A simple antenna that can be erected very fast, only need one center support, and do not take up much storage room. Works from 40 to 10 meters band

Presents a comprehensive guide for constructing a broadband Hex Beam antenna, a popular directional array for HF operation. This design offers a compact footprint and excellent gain characteristics, making it suitable for limited space installations while providing significant performance advantages over omnidirectional antennas. The resource details the specific dimensions for a five-band Hex Beam covering 20, 17, 15, 12, 10, and 6 meters, emphasizing the critical element spacing and wire lengths required for proper resonance and pattern. It outlines the construction of the center post, spreaders, and wire elements, along with the feed point assembly, ensuring proper impedance matching. The project aims for a forward gain of approximately **5.5 dBi** on most bands, with a front-to-back ratio often exceeding _20 dB_. Building this antenna requires careful measurement and assembly, but the resulting performance provides a substantial upgrade for DXing and contesting.

Also known as Magnetic Loop Antennas, by AA5TB. Excellent article on construction tips and tecniques of a Small Loop antenna

This is an attempt to build an Antenna rotator controller using Arduino Mega 2560 with a nice user interface showing the actual position of the antenna.

The W1TAG LF Receiving Loop is a specialized antenna project for LF reception, designed to mitigate local noise and enhance weak signal pickup on the lower frequencies. This square loop, measuring 6 feet per side, utilizes 14 turns of #12 THHN wire wound on a PVC frame, offering a robust mechanical structure. The design incorporates a series-tuned circuit with a coupling transformer, allowing for tuning from over 400 kHz down to _45 kHz_ using a switched capacitor bank. Construction details include the use of 1.5-inch PVC pipe for the frame, with specific measurements for spreaders and drilled holes for wire threading. The two 7-turn sections of wire are connected at the center, providing an option for a center tap. The loop rotates on a 1-inch steel pipe, enabling directional nulling of noise sources. The tuning unit, housed in a box clamped to the PVC, employs a 1:2 step-up transformer wound on an _FT-82-77 core_ and uses relays to switch capacitance values from 50 pF to 6400 pF, providing precise frequency adjustment. The current setup connects to the shack via 100 feet of RG-58, feeding into a W1VD-designed preamp, with plans for a balanced, shielded twisted pair cable upgrade.

A multiband antenna that can work from 80 to 10 meters in this illustrated docuemnt by G8ODE

A quarter wave vertical end-fed antenna for the 40 meters band. As all vertical antennas, also this aerial requires a good earthing system. In this project the ground is composed by twelve 4, wires buried in the lawn by using a spade to create a slit to drop the wire into.

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

MARS, Israel's Antenna and RF System manufacturer, flat antennas for cellular, military broadband, multiband MF high power antenna

Antenna covers all bands 80-10 meters + 30, 17, 12 meter WARC bands, need a lot that is at least 100 feet across.

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

Lot's of antenna planning software mainly in dos version by G4FGQ.

The concept of the "Hula Loop" came after many years of building medium wave loops of varying size, shape and performance. Usually these loops are constructed on a square wooden frame, with wire being wrapped around the periphery

3 Band vertical Marconi-antenna for the bands 40, 80, 160 meters with a ground net of wires as radials.

A 2.4 GHz WiFi antenna that can boost your WiFi signals for many miles. It\'s an easy to build Yagi antenna project done with some popsicle sticks, paper clips and glue.