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A 4 element yagi beam antenna for the 17 meters band with pictures and element dimension and spacing

An EH Antenna for 14 MHz by EB3EMD based on an original project by F5SWN

This online WebSDR is located near Corinne, Utah, has coverage on all U.S. amateur HF, MF and LF bands, 2 meters, the bottom 1 MHz of 6 meters, and several shortwave broadcast bands.

This is a presentation used at OVARC on the LindenBlad antenna construction. The presentation cover several topics about this antenna, from the basic antenna design, to the guide on how to contruct a custom lindenblad antenna for the 2 meters band and and 70 centimenters band.

Amateur Radio 40m 20m 15m Half Wave Fan dipole antenna project with part list, pictures and drawing. Includes the option to expand the antenna to cover the 80 meters band

This article describes the details of the design, which can be easily scaled for just about any HF band. The antenna described in this article is for the 20 meters band.

Article from 73 Amateur Radio Today about experimenting on ferrite loops transmitting loop antennas for 80 and 160 meters bands.

An home made FETer QRP transceiver for the 80 meters band

A dual band delta loop antenna resonating on 30 and 40 meters band using a single wire for the top slopers on both 30 and 40 meters and does not need any balun

A moxon antenna for 2 meters band featuring 6 dBi and a F/B of 30 dBi

An amplifier made using an old HT-41 Hallicrafters Amplifier and adding the 160 meters band By W4NFR

A project with schematic to build a receiver for 80 meters band by VK1PK

An almost invisible wire antenna for the 17 meters band

A bazooka coax antenna for 40 meters band design by CA6TYS

Applied instruments manufactures test and measurement equipment for the broadband telecommunications industry. products include carrier generators, signal level meters, rf switches, spectrum analyzers and a return alignment system.

A 160W linear amplifier for 4 meters band based on GI0GDP

An easy to build dipole for 21 and 14 MHz with traps made by two T50-6 toroids cores mounted on a simple PCB foil

DIY beacon for six meters band by K9MU

KB9AMG's Top WSPR Spots presents a focused online tool for monitoring **2-way WSPR reports**, specifically detailing propagation data from February 2026 through March 2026. This resource aggregates _WSPRnet_ data, allowing radio amateurs to observe weak signal propagation conditions across various bands. The interface is straightforward, presenting callsigns, frequencies, signal-to-noise ratios, and distances for each reported contact, which is crucial for understanding current band openings and signal paths. The utility of this WSPR spotter lies in its ability to quickly visualize global propagation. Users can identify active stations and assess signal viability over long distances, with reports often showing contacts spanning thousands of kilometers. For instance, a typical WSPR report might indicate a signal from Europe reaching North America with a _SNR_ of -25 dB, demonstrating effective low-power communication. This data is invaluable for planning DX operations or evaluating antenna performance under actual propagation conditions.

A dual band portable inverted V antenna for 80 and 40 meters band with dimensions for other bands and several assembling instruction

Homebrew 30 meter full quarter wave vertical antenna.

The 160-meter amateur radio band, spanning 1.8 to 2 MHz, was historically the lowest frequency amateur allocation until the introduction of the 630-meter and 2200-meter bands. ITU Region 1 allocates 1.81–2 MHz, while other regions use 1.8–2 MHz. This band, often called "Top Band" or "Gentleman's Band," was established by the International Radiotelegraph Conference in Washington, D.C., on October 4, 1927, with an initial allocation of 1.715–2 MHz. Effective operation on 160 meters presents significant challenges due to the large antenna sizes required; a quarter-wavelength monopole is over 130 feet, and horizontal dipoles need similar heights. Propagation is typically local during the day, but long-distance contacts are common at night, especially around sunrise and sunset, and during solar minimums. The band experienced a resurgence after the LORAN-A system was phased out in North America in December 1980, leading to the removal of power restrictions.

Complete instructions on tuning the Butternut HF2V on four bands, 80, 40 , 30 and 15 meters

Article on a QRSS receiver for 30 meters band

The resource provides coaxial cable attenuation data, listing signal loss in dB per 100 feet for various cable types across a frequency range from 1 MHz to 5.8 GHz. The initial table details attenuation for cables such as _RG-58_, _RG-8X_, and RG-213, with impedance values of 50 ohm or 75 ohm, at frequencies up to 1 GHz. For example, _RG-58_ exhibits **0.4 dB** loss at 1 MHz and **21.5 dB** loss at 1 GHz per 100 feet. A subsequent table expands on this data, including LMR series cables like _LMR-400_ and LMR-600, along with other types such as 9913F7 and RG214. This section covers frequencies from 30 MHz to 1,500 MHz, also noting the outer diameter of each cable. For instance, _LMR-400_ (0.405" diameter) shows **0.7 dB** loss at 30 MHz and 5.1 dB loss at 1,500 MHz per 100 feet. The final section focuses on VHF/UHF/Microwave amateur and ISM bands, presenting attenuation in dB per 100 feet (and meters) for frequencies including 144 MHz, 450 MHz, and 2.4 GHz. This table includes larger diameter hardline options like 1/2" LDF and 7/8" LDF, in addition to flexible coaxial cables. For example, 1/2" LDF cable demonstrates **0.85 dB** loss at 144 MHz and 6.6 dB loss at 2.4 GHz per 100 feet. DXZone Focus: Coaxial cable attenuation | LMR-400 | RG-58 | 5.8 GHz

An early review of the Icom IC-7300 HF + 6M Transceiver includes four videos demonstrating reception on 40 meters band

This wire antenna for 40 and 20 meter band feature a good SWR. Horizontal side of the antenna is placed at two meters above the ground. Impedance of the antenna are depending by the height of the base from the ground and conditions of the ground

An home made CW beacon transmitter project running 1.5 W on the 80 meters band

Three Yagi antennas for the six meters band by 9A7PJT. Include a 4 element yagi, a custom design 4 element, and a 5 element yagi with antennas pictures and design.

A review of all possible receiving antennas for top band 160 meters

The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

5 Elements 12,5 Ohm Yagi with a 6m Boom

An easy to build and extremely high performance antenna, works perfectly on all HF bands 3.5-28 MHz with some compromises, it is basically an half wave dipole for 40-80 meters, an LC circuit or trap 40 meters allows you to use a single radiating element.

4 Square K9AY Array project for 80 and 40 meters band

Article about an end-fed anntenna for the 17 and 12 WARC Bands. 30 meters is not included in this project. This antenna includes a 14 windings unun impedance transformer using a FT-140-43 ferrite toroid, that should be enought for a 100W PEP.

Setting up a ZZ Wave antenna, a dual band loop antenna covering 80 and 40 meters.

IV3GFN beacon for six meters band

A 102-inch vertical whip, commonly a CB antenna, forms the core of this low-profile 10-meter antenna design, optimized for the 28 MHz band. The construction details specify three 8-foot radials made from scrap wire, connected to a common point. This simple yet effective setup is designed for ease of construction and deployment, making it accessible for operators with limited space or materials. The design emphasizes using readily available components, including PVC pipe for the mast and a SO-239 connector for the feedline, ensuring a straightforward build process for a resonant quarter-wave vertical. Field results indicate that this antenna provides good performance for local and DX contacts on 10 meters, despite its compact footprint. The author, N8WRL, shares practical insights into its construction and tuning, highlighting its suitability for temporary or permanent installations where a full-sized antenna might be impractical. Comparisons to more complex designs suggest that this low-profile vertical offers a respectable signal-to-noise ratio and effective radiated power for its size, proving that simple designs can yield satisfying on-air results.

A moxon antenna for the 50 MHz build with 19 feet of 14 AWG copper wire, and based on a set of PVC pipes. This is an easy to build project that will give you an efficient directional antenna on 6 meters band with low SWR on more than 1 MHz bandwidth.

Pictures, design plan and description of a 5 element yagi antenna for the 4 meters band by 9A7PJT

Six meters is a great band for home built Yagis. The elements are reasonably small, but not so small that building tolerances are critical. With careful construction and detailed instructions, it is certainly feasible to build no-tune Yagis up to 432 MHz.

The antenna in this project is a modification of the techniques used to design a multiband fan type dipole with little or no tuning involved having a total space of 105 feet

Demonstrates the complete design and development process for a **Low Noise Microwave Amplifier** (LNA), beginning with conceptual design and progressing through prototyping. The tutorial series covers the initial stages of a single-ended first gain stage, focusing on critical parameters such as noise figure, gain, and stability. It systematically details the theoretical underpinnings and practical considerations for achieving optimal performance in microwave frequency applications. This resource provides a structured approach to LNA construction, enabling radio amateurs and RF engineers to understand the iterative steps involved in realizing high-performance receive-side amplification. It offers insights into component selection, impedance matching networks, and the measurement techniques required to validate design specifications, particularly for **microwave** band operation where noise performance is paramount.

A Yagi-Mag antenna for the 4 meters band with NEC and MMANA files plans and pictures

Makers of the The Polar Explorer transmitter, which operates on 9 HF bands from 160 through 10 meters and is capable of 500 watt peak output power on SSB, CW, AM, FM and RTTY. It is intended to be used in conjunction with a transceiver.

YU7EF 8 elements yagi antenna for 4 meters band

The Kenwood TS-870S HF transceiver features two state-of-the-art 24-bit 20 MIPS DSP chips, providing over 100dB out-of-passband attenuation and CW bandwidth adjustable to 50 Hz. It operates across 160-10 meters with 100 watts output, incorporating digital filtering, a beat canceller, and 100 memory channels. The radio also includes a transmit equalizer, RX antenna input, and a K1 Logic Keyer, enhancing signal processing and operational flexibility for amateur radio operators. Advanced capabilities include IF stage DSP, dual noise reduction, and an auto notch filter, all contributing to superior signal reception and clarity. The TS-870S offers a variable AGC, voice equalizer, and an RS-232C port for computer control, with Windows™ software supplied. Its built-in automatic antenna tuner functions on all bands for both transmit and receive modes, streamlining station setup and operation. Available accessories such as the DRU-3A digital recording unit, SO-2 high stability crystal oscillator, and VS-2 voice synthesizer option further extend the transceiver's utility. The unit requires 13.8 VDC at 20.5 Amps and is supplied with an MC-43S hand microphone, making it a comprehensive station component.

An home made doblet antenna made with two Slinkys that are aproximately five meters in length connected with a twin-feed connected to a balanced ATU

A monoband delta loop antenna for the 7 MHz. This vertically polarized DX Antenna is a full wavelength sngle side antenna and has a total length of 42.3 meters (137,1 inch) Can be easily setup with a flag pole or fishing pole as center top mast. For optimal performance lower side should be at 2 meter above the ground. This antenna offers a low radiation angle and 1 DB Gain.