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Simple vertical radiator with matching box. No traps, no tuner required for this multiband antenna

HamCalc is a free collection of calculators for radio amateurs include Antenna ERP calculations, Attenuators, Audio Filter design, Coil Winding, Decibels, Great Circles map and calculator, HF Filters, HF Traps, Metric conversions OP Amps QRA Locator to Latitude/Longitude, Radio Horizon calculator, Resonance Satellite orbit calculator Timer calculations (555 timer)Zener Diode calculations Download zip By G4VWL

How to build a G5RV Transmitting antenna Originally posted to the packet bbs system by KC6CFF. The G5RV is an easy-to-build 80-10 dipole requiring no traps. All bands are covered, including 30, 17, and 12. The G5RV has high SWR, by design, on most bands and a tuner is required

Homebrewing traps for the W3DZZ wire dipole Antennas. Article in Dutch with some interesting pictures

A new perspective on the analysis and design of this popular antenna element. By Karl-Otto Muller, DG1MFT

An interesting article about homebrewing antenna traps for multiband antennas by VE3GK

This page describes the design and construction materials W8WWV used to build a coaxial cable trap. A coaxial cable trap is a parallel resonant circuit that is usually inserted in an antenna element to enable multiband operation.

This multiband antenna 10-80 meters is a home made project by I1BAY. Has been used for SOTA activations with great results. Traps are done with coax cable turns, dimensions are in the attached schema.

This improved multiband trap dipole introduces a new trap design and a change in trap location. The antenna features double-coaxial-cable-wound traps having lower reactance and a higher quality factor (Q) than earlier coax-cable traps by W8NX

Basics for a good Antenna:``Only if you can hear it, you can work it!``Symmetric antennas save a lot of trouble.``No traps - no radials - no loading coils.

These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.

An original way to build antenna traps

How repair the traps, and then homebrew the rest of the antenna, including the matching box

This article is to describe a multi band DX-dedicated antenna offering a minimum of compromises (such as lossy traps), for the hams not having any high-support

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.

The Big Signal, W2AU, W2DU, W2VS, traps InLine, Intenna, An-sulator, End-sulator, Old Reliable by Unadilla Antenna Manufacturing Co.

Testing and comparison of traps and trap antennas

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

This article refers mainly to the old Cushcraft 1/4 wavelength AV series of antennas (12AVQ, 14AVQ etc) hence the references to radials. The R series (R5, R7 etc) are 1/2 wavelength antennas, and the radials are NOT 1/4 wavelength resonant.

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency.

Article on maintenance of a FRITZEL antenna by cleaning and restoring antenna traps, baluns and elements.

Analysis of an antenna trap where a coil is formed of a length of coax cable, the outer conductor of one coax end is tied to the inner conductor of the other coax end, and the remaining connections form the terminals for the trap.

Specialist in the design and supply of Radio Communications Equipment and Systems. West Sussex England. Antennas, traps and baluns inline isolators, Outbacker Antennas, Mobile Mounts and Accessories

A 4-Band vertical antenna that needs NO tuner, NO traps. Implement an LC matched on 4 bands with relay switching.

Negatives sides of using trap antennas

Tuning Antenna Traps without a Grid Dip Oscillator, using a bit of initiative and some standard equipment a ham should have in the shack.

Tips on winding wire coils used as inductive loads, traps, band-pass filters, are implemented in a number of amateur radio projects especially antenna projects

Tuning HF Coaxial Antenna Traps

How to home made antenna traps with material you can easily find, and how to properly tune it.

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency. This article explains a method using a RF signal generator at +10dBm output into the coaxial trap.

This antenna is a classical antenna working on 7,10,14,18,50 MHz is implemented with three traps for 30, 17 and 6 meters

Discovering a solution for limited space, the inverted L HF antenna emerges as a stellar performer. Half the size of a dipole, it ensures optimal installation in restricted areas, maintaining superb transmission (TX) and reception (RX) characteristics. Spectrum Communications' multi-band version, featuring traps, proves even more space-friendly without compromising performance. A fiberglass pole offers sturdy support, while proper grounding, an RF choke, and occasional tuning contribute to a high-performing and reliable antenna system.

A document that will guide you on Coaxial-Cable trap optimization process to gain on global antenna performance and on increasing effective bandwidth.

RF traps for a lightweight 40/30/20/17/15m inverted V dipole antenna for SOTA purposes and how you can use a modern antenna analyser to find the resonant frequency of a HF trap.

This article describes a multi-band antenna design for amateur radio enthusiasts by G3FEW. The antenna is designed to cover at least five HF bands with low SWR and without the need for an ATU. It is also designed to be easy to construct and adaptable for different locations. The antenna is a full-wave dipole with traps at the quarter-wave points. The traps are used to tune the antenna to different bands. The antenna can be fed with a 4:1 balun. The article includes instructions for building the antenna, as well as information on the theory behind its operation. The author also discusses the results of his tests with the antenna. This multi-band antenna is a well-designed and versatile antenna that can be used by amateur radio enthusiasts on a variety of bands. It is relatively easy to construct and can be adapted for different locations.

A 3 band dipole antenna for 40-80-160 meter bands, It's made with easily available materials and is designed for inverted V mounting. The antenna is shortened for these bands, but still manages to make contacts in 80m and 160m with stations in Canada and the USA. The construction details are provided, including the dimensions of the antenna elements and the traps. The antenna is easy to build and provides good performance in all three bands. In Italian.

A Trapped dipole inverted V antenna for lower HF Bands. Construction details are for temporary installation. Permanent installations will require additional ruggedising and waterproofing however the basic electronics concepts remain the same. This project includes SWR plots for the three bands and pictures details of the homemade traps.

This article details the author's process of designing and building a trap dipole antenna for the 17, 12, and 6-meter amateur radio bands using a Yaesu FT-450 transceiver. The antenna incorporates parallel-tuned circuit traps to enable operation across multiple bands without switching aerials. Key construction details, including coil and capacitor specifications, are discussed, along with the testing results, which include successful long-distance communications on the 50 MHz band. The article highlights the flexibility of home-built antennas and provides insights for amateur radio enthusiasts looking to optimize multi-band performance.

This document provides comprehensive guidance on modeling and constructing multiband dipole antennas using traps. It addresses common segmentation issues in EZNEC modeling software, recommends optimal segment lengths for trap models, and compares trapped dipoles with paralleled multiband dipoles. While trap dipoles are significantly shorter, they exhibit lower gain and narrower bandwidth. Detailed instructions for building weatherproof coaxial traps include material lists, construction steps, and tuning methods. The guide notes that properly constructed coaxial traps introduce only minimal signal loss (0.6 dB) while offering practical multiband performance in a compact design.

Rob Conklin N4WGY delivered an informative presentation on Hexagonal Beam antennas (Hex Beams), detailing their construction, performance, and benefits over traditional multiband Yagi antennas. He highlighted their cost-effectiveness, lower wind loading, lightweight design, and multi-band capabilities without requiring traps. Conklin also discussed the improved G3TXQ design, which offers better SWR performance across ham bands. The presentation included practical construction tips, resource recommendations, and demonstrations of performance analysis tools, making it a valuable resource for both novice and experienced antenna builders.

Learn how an experienced ham radio operator rebuilt his trap dipole antenna for 30, 40, and 80 meters after a storm damage. Discover the process of upgrading to a short trap dipole for 40, 80, and 160 meters using double-wound traps made from RG-58 coax. Follow along for construction details and tips on building this unique classi.