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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.

This 80M antenna is a pair of raised 1/4-wave verticals

A 4 element addition for 10m to an existing 4 element yagi (ZX antennas)

Prince Edward Island. The PEI DX Lodge offers a turnkey operation from a custom designed shack featuring state of the art transceivers/amplifiers, etc. and the ultimate in antennas on every band.

Raising large Yagi antennas can be a challenging project. A trolley system will make the job a lot easier

All about homebrew, antennas, accessories for shack, digital tecniques and more..

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor

Similar to Tiny 2 but this three element direct connect antenna utilizes a reflector and a director to achieve gain.

An online J-Pole antenna calculator that need just to input the frequency and calculates in inch size of each element

Memorandum on the Beverage Wave Antenna for Reception of Frequencies in the 550 - 1500 Kilocycle Band", FCC Report 9.2.1, by Benjamin Wolf and Adolph Andersen

The page provides a project for an helical dipole for the 40 meters band, resonating on 7 MHz, created by PY1ZFK based on a design by DL8VO. It includes detailed instructions on building the antenna.

Arab Amateur Radio orum. Transceivers , Antennas, Educational, Software, Digital Communication and more.

SecondHandRadio.com provides a platform for the amateur radio community to buy, sell, and swap used, surplus, and obsolete electronics and electrical equipment. The site facilitates transactions for a wide range of items, including ham radio transceivers, test equipment, shortwave receivers, antennas, and vintage radio components like tubes. Users can place classified advertisements with photos at no cost, catering to individuals, radio clubs, and commercial dealers seeking to liquidate or acquire gear. The platform emphasizes ease of use with a straightforward sign-up process and no associated fees or commissions for listing or selling items. It positions itself as a primary resource for used electronics within the USA, fostering a direct connection between sellers and buyers without intermediary charges. The service supports various categories beyond amateur radio, extending to military radios and antique equipment, thus serving a broad spectrum of radio enthusiasts and collectors.

The G7FEK Multi-Band Nested Marconi Antenna, a small, efficient all-band antenna.

SWR (standing wave ratio), is a measurement of how efficiently your antenna system will radiate the power available from your radio. In simple terms, your radio would like to radiate all of its power, but can only do so if the other components cooperate

Presents a QRP AM/CW transmitter project specifically designed for the 10-meter band, utilizing a crystal oscillator and a collector-modulated AM oscillator. The design employs a 2N2219(A) transistor in a Colpitts configuration, generating 100 to 350 mW of RF output power depending on the 9-18 Volt supply voltage and modulation depth. Frequency stability is maintained by a 28 MHz crystal, with fine-tuning possible via a Ct1 trimmer capacitor for approximately 1 kHz adjustment. The resource details the RF oscillator stage, implemented with a 2N2219 NPN transistor, emphasizing frequency stability and low power dissipation. It also covers the amplitude modulation stage, managed by a 2N2905 PNP transistor, which impresses audio information onto the carrier. Selective components (C3, C4, C7, C5) enhance voice frequencies within a +/- 5 kHz bandwidth, and modulation depth is controlled by R2 and R3. The project includes a 3-element L-type narrow bandpass filter (Ct3, L3, C10) to suppress harmonics and ensure a clean output signal. The project provides a complete schematic diagram, a comprehensive parts list including specific capacitor, resistor, and inductor values, and construction notes for the coils (L1, L2, L3). It also offers practical advice on enclosure requirements, suggesting an all-metal case or a PVC box with graphite paint for RF shielding. Operational parameters such as current draw (27mA@9V to 45mA@16V) and input impedance (50 Ohms) are specified, alongside guidance on antenna matching and the importance of a valid amateur radio license for 10-meter band operation.

The antenna build into this project is made from 2 fishing poles on a fiberglass pole in the center.

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

The antenna is a VHF side is a 2m moxon, tuned on 145.825 MHz. The driven element of the moxon couples to a driven element for a 5 element 70cms Yagi, tuned on 436.5 MHz.

Experiments with spiral dipole antennas. Includes two spiral antenna designs for 20 and 40 meters band by KN9B

A switchable Magnetic Transformer for Transmitting for various impedances

Configurations of the vertical antenna arrays used at 6Y2A

Constructing the QE19 Antenna Launcher

Experiments on remote receiving loops antenna by Lyle Koehler, K0LR

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.

This handy and cheap portable dipole can be folded and backpacked, carried in use, and adjusted to a very wide range of frequencies by KV5R

Inspired by Milan OK7GU, the goal is to build an universal antenna controller - for different types of rotor, different motor, encoder

This modification will allow the use of separate receive and transmit antennas on the Kenwood TS-850S/AT.

The _Italian VHF Beacons_ resource provides a detailed listing of active and QRT amateur radio beacons operating across VHF, UHF, and SHF bands within Italy. Each entry specifies the beacon's callsign (e.g., IQ1SP/B), operating frequency (e.g., 144.411 MHz), QTH locator (e.g., JN44VC), effective radiated power (ERP) in watts, and antenna configuration (e.g., Big Wheel, 4x Dipole, Yagi). This data is crucial for radio amateurs involved in propagation studies, equipment testing, and long-distance (DX) communication on these higher frequency bands, offering fixed signal sources for monitoring. This compilation, last updated in October 2005, serves as a historical snapshot of Italian beacon activity. For instance, it lists several 144 MHz beacons with ERPs ranging from **0.1W** to **10W**, and higher frequency beacons such as I8EMG/B on 1296.880 MHz and I3EME/B on 24192.132 MHz. The inclusion of QRT (Quiet Radio Teletype) status for many entries indicates the dynamic nature of beacon operations over time. Users can utilize this information to identify potential signal sources for band openings or to calibrate their receiving equipment against known transmissions.

Home made WiFi 11dBi, wide band antenna by T. Marshall

How to build a slingshot antenna launcher. Slingshot antenna launchers are used to launch a line over a tree branch, so antennas can be suspended from high up trees

About the clemens match for beam antenna, as an alternative to common gamma matching techniques

Italian web site describing a project for a 2 meters home made halo antenna

Using a full-size antenna and a reasonably sensitive headphone, this simple switching mixer will produce an amazing abundance of signals on 80m.

probably the most simple and inexpensive antenna you could make for 23cm.

Triband DK7ZB VHF Yagi antenna for 6 m, 4 m and 2 m with a single feedpoint

T2FD A practical construction article, which first appeared in the Electronic DX Press, contains a number of useful photos and detailed instruction to build this antenna by VK3BVW

The skeleton slot antenna design was developed in the UK for TV use soon after WW2. This document describe and adapted version for the 2 meter band

Package contain 1x yaesu vx-8r 1x sma dual section antenna 1x hf antenna lithium ion battery pack fnb-101li 1x battery charger nc-86c 1x connector unit

Convert a Hustler 5 band 5BTV to 17 Meters An easy add on antenna project by Larry, KK5ID

A small random wire antenna tune that can tune from 40 to 10 meters bands.

The EggBeater Antenna web page by ON6WG F5VIF a web site dedicate to this VHF UHF antenna

A ferrite antenna for Low Freqencies

40/20/10 Meter Fan Dipole attic antenna article by KD2GOE

Exagonal Beam antenna cover 20-17-15-10 meters By KE4NU

The SCOTIA Bandhopper a mobile multi-band vertical antenna

A web site dedicated to hex beam homebrewing. The hexagonal beam has become a wildly popular antenna. It is a directional antenna that provides great performance and does not require a full scale, expensive tower.

The 1960s mobile/base antenna returns, double G Whip for base use.

A 5 element wide spaced yagi for the 20m long path to Europe was installed at ZL6QH, the antenna is fed with a 600 ohm open wire feed line.

Experiments on HF antennas for restricted spaces. In this article author experiments antennas for 80-10 meters band having just a very small garden and several restrictions. Basic antennas consists of laded multiband dipoles and fan dipole antennas