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This article describes how an effective ground system can be produced for a short vertical antenna.

Over 25,000 amplifiers and sub-assemblies were produced by Angle Linear for the communications industry over a 40-year period. The company specialized in **high-linearity RF products**, focusing on preamplifiers, bandpass filters, and receiver multicouplers. Specific product lines included PHEMT and GaAs FET preamplifiers, offering both quadrature and single-ended configurations for various signal levels. The offerings encompassed coaxial and combline bandpass filters, along with integrated filter-preamplifier assemblies. The company also provided custom RF assemblies, addressing applications such as MRI preamplifiers, passive radar, and EME (moon bounce). Their product range covered VHF and UHF frequencies, including specific designs for 2m, 70cm, and 23cm bands, often featuring high IP3 performance. Technical documentation, such as filtering application notes and duplexer theory, was also associated with their product offerings.

Build your own multiband W3DZZ antenna resonating on 80 40 20 15 and 10 meters band

This Vertical antenna design by David Reid for lower bands focuses on achieving effective DX communication by optimizing the antenna low-angle radiation for long-distance contacts. The design incorporates techniques like linear loading and capacity hats to reduce the antenna's height while maintaining performance, especially on 40m and 80m bands. Building a solid ground plane and using quality materials ensure efficiency and durability. Although vertical antennas can be complex to build, this project simplifies the process, making it accessible for ham operators seeking strong, reliable signals.

Installing your dipole end insulators, a beginner guide to proper setup wires to insultaors.

A well documented plan to build a magnetic loop antenna for Shortwave Listening, includes photos and diagrams.

Practical contruction and designing notes of a delta loop for the 40 meters band

90 foot tall top loaded vertical for 160 meters

Details the construction and optimization of antenna systems for amateur radio satellite operations, focusing on practical, homebrew solutions for VHF/UHF bands. It covers building _groundplane antennas_ from salvaged materials, recycling old beam antennas into new configurations like a 2-meter crossed yagi, and constructing a 10-meter horizontal delta loop. The resource also explains antenna matching techniques, including folded dipole driven elements and quarter-wave transformers, along with the importance of accurate SWR measurements and minimizing coax loss. Demonstrates how to achieve a **1:1 SWR** by carefully trimming elements and adjusting radial angles on groundplane antennas. It provides insights into selecting appropriate coax and connectors, highlighting the benefits of Belden 9913 for low loss and the proper installation of _N-connectors_. The article also addresses RFI mitigation from computer birdies and presents a design for a silent triac antenna control circuit, offering practical solutions for common satellite station challenges.

The G3JVL 6 Meter ground plane vertical is a compact antenna that is ideal for portable operations. If needed, it can be disassembled into a very small bundle no longer than the longest element.

Homebrew a 5/8 wave ground plane antenna for 10 meter band. Interesting article with lots of pictures and homebrew details.

VHF magnetic loop atenna by ON1DHT

A magnetic loop antenna for 144 mhz, two meter band

Improve your 80 and 160 meter signal without a Yagi!

Specializes in antique radio schematics, circuit diagrams and service data for vintage tube radios. Carries information for American, Canadian and European antique radios.

A simple and cheap dualband j-pole antenna for 144 and 430 MHz

A vertical antenna for stationary-mobile HF-VHF operation. It works on 2-6-10 and 12 meters band.

Magic Anti-Jamming antenna for shortwave reception

To connect up your FT-817/857/897 to a PC you have a number of options. For the serial connection you can go ahead and obtain a CT-62 from YAESU. Alternatively you can make up your box with a level converter and cable using schematic in this page

The dipole antenna is an easily designed and made antenna usually used on HF, although can be (and sometimes is) made for VHF and UHF antennas, and in varying forms is also used as part of different designs of antennas i.e. as the driven element for directional antennas.

An easy guide to "How to build your own magnetic loop" for 20 meters

Magnetic loops are a compromise antenna and performance will be down on a full size-wire antenna particurlarly on lower HF Bands. This article compare this magnetic loop with a full-sized wire antenna on 80 meters by VK3YE

Presents the KE4UYP linear-loaded vertical antenna design, which introduces very little loss on 80 or 160 meters, achieving an overall radiation efficiency of 80% to 85%. This design addresses common pitfalls of traditional base-fed verticals by placing the majority of the current at the top of the antenna, eliminating the heavy reliance on extensive ground radial systems. The author's initial 10-meter model, only three feet tall, yielded 5/9 signal reports to Anchorage, AK, and Europe, confirming its effectiveness. The antenna incorporates both vertically and horizontally polarized radiators, with a 1/4 wavelength horizontal counterpoise located at the feed-point, near the top, to create an almost totally omnidirectional pattern with high wave angle horizontally polarized radiation. This dual polarization ensures even illumination across all take-off angles, making it effective for both local contacts and **DXing**. The vertical element is linear loaded, adding capacitance reactance and making it longer than the horizontal element to achieve resonance and raise the feed-point impedance to 50 ohms. Fine-tuning the antenna requires careful adjustment, as tower reactance can vary. The article suggests starting with 80 feet for 80m and 170 feet for 160m for the vertical wire, then trimming for resonance. Bandwidth specifications include 300 kHz under 2:1 **SWR** on 80m and 100 kHz on 160m when suspended between trees, or 150 kHz on 80m when side-mounted on a tower.

The Flower Pot Antenna project details a portable dual-band antenna primarily operating on 10 meters, with secondary resonance near the 30-meter band. Construction involves winding RG58 coaxial cable uniformly around a large plastic flower pot, approximately 70cm high with a 60cm top diameter. The design eliminates the need for radials, contributing to its compact and lightweight nature. Key construction steps include soldering the inner conductor to the shield at one end of the wound cable and connecting the wound cable's shield to the rig cable's inner conductor at the base. An LC network, comprising a variable capacitor (0-200pF) and an inductor (10 coils, 5cm diameter, 2mm wire), is inserted between the wound cable's inner conductor and the rig cable's shield. Tuning is performed with an antenna analyzer, adjusting cable length and the variable capacitor for optimal impedance on 10 meters. The antenna performs effectively when installed horizontally.

A 40 meters band full wave antenna project plan with model, adding the Missing Leg to the Inverted-L Antenna

A 20 and 40 meter vertical on Autopilot by K6MHE PDF File

Build your own antenna for the 23cm band ( 1250Mhz - 1280Mc ) using some aluminium and this simple design.

info on marine radio frequencies

G3JVL Six meters ground plane vertical is a compact antenna that is ideal for portable operations on 50 Mhz

Baluns what do they do, in a pdf file by W7EL

An inverted U wire antenna for 200 meters and down

Build the PAC-12 Antenna a multi-band portable vertical designed by KA5DVS, here's an award-winning, easy-to-homebrew, multi-band portable vertical antenna designed by long-time antenna aficionado James Bennett, KA5DVS. He's documented the design and construction plans for a portable antenna

a guide to help install arrays

U6YRN 6 element yagi antenna for 430-450 Mhz

This drawing shows a simple 10 meter wire J-pole antenna designed for 28.4 MHz. It is a vertical, end-fed Zepp-style antenna made from common materials and intended for easy home construction. The main radiating element is a straight length of stranded copper wire, either 14 or 18 gauge, cut to about 16.5 feet. At the top, the wire is supported by an insulator, allowing the antenna to be hoisted vertically. The matching section is made from 450-ohm ladder line, approximately 7 feet 9.5 inches long, and shorted at the bottom. This matching stub transforms the impedance so the antenna can be fed with coaxial cable. The feed point is tapped about 6 inches above the bottom of the stub, with the shield and center conductor connected at the proper points. A choke balun is formed with five turns of RG-58 coax in a 4-inch diameter loop to help reduce unwanted RF on the feed line. The drawing notes that this antenna has about 0 dBd gain, similar to a dipole, but offers an omnidirectional pattern and low-angle radiation when installed high. Its main advantage is practical performance, simple construction, and effective coverage for 10 meter operation.

This rugged antenna, an omnidirectional collinear, is capable of surviving harsh environments. It's a good choice for repeater installations and can be top, or side mounted to the tower by WA6SVT

This antenna is intended as a simple, inexpensive solution for the newcomer to experiment across the 40m band (7.0-7.2MHz) when only restricted space is available

A 14 Mhz version of the vertical moxon antenna homebrewed.

The _Astron RS35m Power Supply Schematic_ provides a detailed circuit diagram for this popular linear power supply, focusing on the rectifier and pass transistor stages. It presents the AC input and DC output sections, illustrating the component layout and interconnections critical for understanding its operation. The schematic is enhanced with specific annotations derived from the December 2005 QST "Hands-On Radio, Experiment #35 Power Supply Analysis." These notes offer insights into the circuit's functionality and potential analysis points, making the diagram more instructive than a bare schematic. The resource serves as a practical reference for hams interested in the internal workings or maintenance of the _Astron RS35m_ unit. This document specifically highlights the key components responsible for voltage regulation and current delivery.

Contain schematic diagram of many different radio, and some operations instructions.

Demonstrates _Freq51_ and _Specgrm2_, two analysis programs from the Biomedical Ultrasonics Laboratory at the University of Michigan, available for DOS or Linux. The _Spectrum Analyser (Freq51)_ provides power spectrum levels as a function of frequency, configurable for absolute values (e.g., dB re 1 volt) with sound card calibration. _Spectrogram (Specgrm2)_ generates a real-time, full-screen spectrogram (sonagram) with various color options. These programs analyze incoming signals in real time, not stored files, and offer extensive settings for sampling rate, FFT points, and averaging time, making them highly versatile for acoustic analysis. The DOS version of _Freq51_ and _Specgrm2_ can operate under Windows 95, requiring users to configure sound card switches via a text file. The resource also briefly mentions other acoustic analysis software like Gianni Pavan's DOS-based bioacoustic tools, _Gram_ by R.S. Horne for Windows, _SASLab_ (Light and Pro versions), _Cool Edit_, and _GoldWave_, providing a comparative overview of available tools for real-time and file-based spectral analysis and waveform manipulation.

Build a PSK-31 PC interface for the yaesu FT-817

The resource provides detailed information about a five-band indoor magnetic loop antenna designed for amateur radio operators. This antenna is capable of operating on the 20, 17, 15, 12, and 10 meter bands, making it a versatile choice for various HF communications. Constructed from a single 3-meter length of 22 mm copper tube, the design emphasizes compactness and efficiency, which is particularly beneficial for operators with limited space. The page includes insights into the construction process, tuning, and operational tips, catering to both novice and experienced users. In addition to the technical specifications, the resource also discusses the advantages of using a magnetic loop antenna indoors, such as reduced interference and improved performance in urban environments. It serves as a practical guide for those interested in building their own antenna, offering a straightforward approach to antenna design and construction. Overall, this resource is a valuable addition to the toolkit of amateur radio enthusiasts looking to enhance their station with an effective indoor antenna solution.

Some practical indoor antennas that can be built by anyone

Examines the current geopolitical landscape of Armenia, offering detailed reports on regional developments and internal political discourse. The station, _Radio Azatutyun_, covers critical discussions such as the potential for conflict in September, with one source suggesting a "war is coming, it won't be delayed," alongside ongoing debates about Armenia-EU visa liberalization, which is projected to require "another 2-3 years" for completion. It also highlights the contentious rhetoric surrounding the Prime Minister's interactions with displaced persons from Artsakh. The resource delves into significant international relations, including discussions between Bayramov and Araghchi on regional situations, and Iran's denial of recent negotiations with the US. It also features updates on former President Trump's demands for an additional **$200 billion** for defense and his assertion that "regime change" in Iran is effectively underway. Further content includes analyses of drone attacks in Baku, the proposed new Constitution, and local issues such as the delayed reconstruction of Gyumri's central market and the persistent problem of Vanadzor's temporary kindergartens. The platform also hosts podcasts like "The Choice is Yours," exploring the reliability of pre-election polls.

The Bruce array is a simple, often-forgotten wire antenna array that is advantageous for 80 and 160 meters, where typical gain antennas are very large. This bi-directional broadside vertical array is only 1\4 lambda high and does not require a ground system. It offers substantially greater SWR bandwidth than the half-square or bobtail curtain. A 4-element Bruce array used by N6LF showed a gain of about 4.6 dB compared to a 1\4 lambda vertical with 8 elevated radials, with a 2:1 SWR bandwidth greater than 400 kHz. The antenna is simple and its dimensions are flexible.

This design represents the smallest practical antenna for Oscar-13 mode-S. Perfect beacon reception at all times is possible, and acceptable SSB even at 43,000 km range.

There are many incorrect ideas and claims surrounding end-fed vertical antennas (like the I-Max 2000), end fed horizontal antennas, Zepp, and J-pole antennas. This article describes it.

A bazooka antenna project for the 7 Mhz, includes dimension for to homebrew your own bazooka for HF bands

This project details three variants of a vertical half-wave antenna design for the 4-meter (70MHz) amateur radio band. The antennas use end-feeding with a parallel-tuned circuit for impedance matching to 50-ohm coaxial cable. The first variant uses suspended flexible wire for portable use, the second employs a fiberglass rod with internal wire for permanent outdoor installation, and the third utilizes aluminum tent poles for quick mobile deployment. Despite the narrow bandwidth of the matching circuit, this suits the narrow 4m FM allocation well. The design offers an effective omnidirectional radiation pattern and can be constructed with readily available materials.