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By ON4CFC Pascal, describe how to build a Sperrtopf or Sleeve antenna for the 144 Mhz, PDF File by antennex

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

Maldol MFB-300 all band HF vertical antenna review by Steve Nichols

Schematic Manual of the 3 element Yagi antenna by ECO antenne

Antenna switch at K6XX

Portable magnetic loop antennas - G4TPH Mag-loop antennas Reviewed in PW and RadCOM, Both QRP and QRO, Portable. The only Magloop on the market that is fully portable

A beam fractal antenna for 20 meters band

6 element super duper moxon antenna for the 144 MHz, a modified HAARP Antenna projetc

A 40-meter antenna that provides good local and regional coverage during the day and good DX capability at night

Radial systems for elevated and ground mounted vertical antennas by SteppIR

A home made vertical polarized moxon antenna for 144 MHz, includes dimensions, antenna pattern, SWR and antenna gain plots by WB5CXC

This design was adapted from an article in the ARRL Handbook and built with simplicity and duplicity in mind. This antenna is a vast improvement over a standard dipole with a forward gain of around 8db with a front to back ratio of 10db.

A compact multiband wire antenna suitable for portable operations.

A full size delta loop antenna for top band by PA3FUN

An efficient 2 meter antenna disguised as a TV Satellite dish. This vertically polarized horizontal slot antenna, cut into the reflector of a TV dish, might be the ultimate stealth antenna.

A monoband antenna with large bandwidth in French

Excel spreadsheet that help calculating dimensions of a high efficiency magnetic loop antenna for HF bands. Giving in input the loop perimeter, loop diameter and loop conductor will calculate electric characteristics, bandwidth, and efficiency

W3EDP multiband wire antenna, an extensive study and analysis of this antenna by W0ESE

Gap Titan DX Antenna manual. This is an enhanced version of the common Gap Titan DX Manual document you can download from other sites. This manual is in PDF Format.

Progress in Design of Extremely Short Transmitting Antennas Short and still efficient, how is that possible? By Juergen Schaefer, DL7PE author of the MicroVert antenna concept. The MicroVert introduced in this document is an extremely short and hardly visible short-wave antenna with outstanding radiation properties

eHam users review of the Cushcraft R7 multiband vertical antenna

Review by G3TXQ and comparison to its modificated versions. SWR Measurements on inverted V setup and comparison from EZNEC model and a real one.

With over 20 years of experience, Proyecto 4 operates as a specialized ham radio retailer in Madrid, Spain, providing a diverse inventory of transceivers, antennas, and related accessories. The store features popular models like the _ICOM IC-705_ and _ICOM IC-7300MK2_, alongside Yaesu transceivers such as the _FTX-1 Optima_, which delivers 100W on HF and 50W on V/UHF bands. The product range includes mobile and portable antennas, such as the D-Original DX-NR770HB, offering 3 dB gain on 144 MHz and 5.5 dB on 430 MHz, and the Diamond RH-770 with a BNC connector. CB radio enthusiasts can find the Anytone CB SMART II AM/FM transceptor and the Telecom LS145 mobile antenna, rated for 500W and 4 dB gain on 26-30 MHz. Proyecto 4 emphasizes its in-house technical service, inviting customers to visit their laboratory for repairs and technical consultations via sergio@proyecto4.com. The store also highlights customer reviews and offers promotions like Yaesu Cashback, providing savings up to 100€.

Demonstrates the design and construction of a compact, portable multi-band mini-delta loop antenna, specifically optimized for /P (portable) operations from remote locations like Scottish islands. The resource covers the theoretical underpinnings of half-wave loops, contrasting closed and open configurations, and then details the application of a folded dipole principle to achieve a 50-ohm match for direct coax feed. It presents empirical formulas for calculating element lengths, considering the velocity factor of common wire types, and provides a detailed example for a 20m (14.175 MHz) version. The article includes a comprehensive table of dimensions and allowances for a five-band (20m, 17m, 15m, 12m, 10m) mini-delta beam, along with construction hints for the central support and balun. It specifies a 1:1 trifilar balun wound on a ferrite rod and describes the antenna adjustment process using an _MFJ-259B Antenna Analyser_. Initial test results indicate an SWR of 1:1 at resonance and a bandwidth of approximately 240 kHz on 20m, even at a low height of five feet above ground. The distinctive utility lies in its focus on a practical, easily deployable beam antenna for portable DXing, offering a viable alternative to more complex or larger arrays.

A 3 element yagi antenna project for the 144 MHz band by PY5ALZ in portuguese

A 500-watt mobile antenna project details the conversion of an old 10m hamstick into a highly efficient, multiband "bugstick" for HF operation. The core modification involves replacing the original coil with 25 turns of 6 turns-per-inch, 1.5-inch diameter coil stock, fabricated from #14 wire. This design, intended for a 3-magnet mount on a vehicle cab, achieves resonance on multiple bands by shorting out specific turns on the coil, similar to a **bugcatcher** antenna. Measurements taken with an MFJ-259 analyzer on a GMC pickup show 0 turns shorted for 20 meters (14.2 MHz), 10 turns for 17 meters, 16 turns for 15 meters, 19 turns for 12 meters, and 23 turns for 10 meters. The construction emphasizes using UV-resistant tie-wraps and #14 solid wire with crimp lugs for robust RF connections, bypassing the fiberglass rod for current flow. A bonus section details a 40-meter version, utilizing 48 turns of 8 TPI, 2-inch diameter coil stock.

A vertical antenna that can cover HF bands using an UN UN and a fishing pole, usage of tuner is requested.

A moxon antenna project for the 145 MHz

An Off-center-feed antenna that covers 80, 40, 20, 17, 15, 12, 10, and 6 meters

An interesting article by K3DAV comparing the COMET CHA250B to other HF multiband vertical antennas

Review by Peter Bacon, G3ZSS

A PDF presentation of a home made moxon antenna for 50 MHz 70 MHz and 144 Mhz. The project is mainly out of surplus plastic Plumbing pipes and clips etc, and also details of how the dimensions were calculated.

A bowtie antenna is a type of antenna that reputedly provides higher gain at lower radiation angles than a center-fed dipole antenna at heights considerably less than 1/2 wavelength above ground.

An active receiving antenna for 10 KHz to 20 MHz, a very small sized antenna with excellent performances in noise to signal ratio.

This document contains the detailed instructions to build a homemade lindenblad antenna using a twin-lead as dipole elements. This document contains 9 pages and includes a detailed construction sequence and some drawings to build this antenna for UHF and VHF ham radio bands

Build this cheap and easy satellite downlink antenna

Adding extra directivity to the Moxon Rectangle for 6m, 4, and 2m

A moxon rectangle for 50 Mhz band

VHF UHF diplexer by G8MNY

An 80 meter band vertical loop antenna setup

A compact antenna for 160 meters, suitable for hams tha want operate top band buh have a limited space

An home made vertical dipole antenna made with simple material. The antenna has a total length of aproximately 16 feet. In this article appeared on June QST 2019, the author explain how he reached the optimal confirugation changing and adjusting the lower part of the antenna, trimming and spacing correctly the copper wire. PDF File to downloas

A multiband vertical dipole antenna by ON4BAI

Optimizing performances of the end-fed antennas QRP quarterly article

eham users review of the Cushcraft r5 vertical antenna

Optimization tests of the W3EDP multi-band HF wire antenna a popular aerial among QRP enthusiasts because it is light weight and cheap.

Optimizing the ZS6BKW antenna for full HF band coverage often requires specific modifications beyond its standard configuration. This resource details several enhancements, beginning with a simple series capacitor to improve 80m SWR, a technique W5DXP found effective for permanent installation due to its minimal impact on higher bands. Further improvements include a 10-inch parallel open stub for 10m resonance, shifting the frequency to 28.4 MHz with an SWR of approximately 1.8:1, a practical solution for Technician class operators. The document then explores a switchable matching section, adding or subtracting one foot of ladder line at the 1:1 choke-balun, which significantly impacts higher frequency bands and eliminates the need for a tuner on 17m. W5DXP's _AIM-4170D_ antenna analyzer measurements confirm these effects. More advanced modifications involve a parallel capacitor for further 80m SWR reduction, requiring remote switching for multi-band operation, and relay-switched parallel capacitors at specific points on the 450-ohm matching section to achieve low SWR on 60m, 30m, and 15m. These detailed steps, including _Smith chart_ analyses for the challenging bands, aim to transform the ZS6BKW into a truly all-HF-band antenna, reflecting W5DXP's practical experience in antenna tuning.

A multi-band portable vertical antenna can be built with relatively ordinary components obtained from the local hardware store, including replaceable loading coils

The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced.

The SCOTIA Bandhopper a mobile multi-band vertical antenna