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A home made project, scan and monitor the 2.4 GHz band using a common MMDS downconverter.

Mounting on Roof or at Ground Level? Why ground plane antenna works better at lower level.

TenTec 1208CY 10/50 MHz Transverter modification by DF9CY

A simple to build full length 20/40 dipole antenna to be used in inverted vee configuration

A step by step approach for a ham radio vertical antenna mount using only a hole, gravel and a piece of plumbing pipe

Use this online calculator to determine the length of a quarter-wave antenna from the frequency. Both metric and English units of measurement are supported.

This project produces a sturdy tripod for small vertical antenna support using readily available electrical metal tubing (EMT) or conduit

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. As many attest, there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. The Super-J has very little separation between the two half-wave radiators.

Protecting amateur radio equipment from transient overvoltages requires robust lightning and surge protection, which is the focus of Electronic Specialty Products. The company provides various devices, including coaxial lightning arrestors for antenna feedlines and surge protectors for AC power lines and data circuits. These devices are engineered to divert high-energy surges, such as those caused by direct or indirect lightning strikes, away from sensitive transceivers, amplifiers, and computer components, thereby preventing catastrophic damage. Key products include the _Coaxial Lightning Protector_ series, designed for various impedance levels and frequency ranges up to 3 GHz, and the _AC Line Surge Protector_ for shack power distribution. Effective deployment of these protection devices can significantly reduce the risk of equipment failure and ensure operational continuity during severe weather. For instance, a properly installed coaxial arrestor can handle peak currents of **20 kA**, while AC line protectors offer clamping voltages typically below 400V. Comparing different models reveals varying levels of insertion loss and return loss, with some coaxial units exhibiting less than 0.1 dB loss at 500 MHz, making them suitable for high-performance HF and VHF/UHF operations. Integrating these components into a comprehensive grounding system is crucial for achieving maximum protection against both common-mode and differential-mode surges.

C-Poles for 20m and 6m, it is a folded half-wave dipole with an asymmetrical tapped 50-Ohm-point in the lower part of the antenna. Design hints by DK7ZB

Demonstrates the operational status and reception reports for the SK6RUD/SA6RR QRPP beacons, which transmit on 478.9 kHz, 1995 kHz, 10.131 MHz, and 40.673 MHz. These beacons utilize extremely low power, with the 630-meter beacon operating at approximately 0.1 watt ERP into an L-antenna, showcasing the potential for long-distance contacts under favorable propagation conditions. The site details the specific frequencies and antenna types employed, such as a vertical at 500 kHz and a 1/4 vertical for higher bands. The resource compiles over 10,530 reception reports from amateur radio operators worldwide, logging details such as date, time, band, RST signal report, locator, distance, and receiver setup. Notable long-distance reports include a 500 kHz reception by AA1A-Dave from 5832 km in 2008 and a 10.133 MHz reception by ZL2FT-Jason from 17680 km in 2010, illustrating the global reach of these low-power transmissions. Each log entry provides specific equipment used by the reporting station, including transceivers like the Yaesu FT817, ICOM IC-7300, and various antenna configurations such as coaxial mag loops, inverted Ls, and end-fed wires. The primary objective of the SK6RUD beacons is to challenge conventional notions of power requirements for effective two-way communication, proving that contacts over significant distances are achievable with minimal output. The site also includes a submission form for new reception reports, fostering community engagement and continuous data collection on propagation phenomena across different bands. The detailed logs offer practical insights into real-world propagation characteristics and the efficacy of QRPP operations.

A conversion of a 80m dipole into a 160m vertical antenna

An indeal stealth antenna made by multiple quarter wave verticals, supported by a tree.

Butternut article on radials usage on vertical and ground plane antennas

Transverters-Store is a online shop for low cost transverter boards, but also QRP transceivers, Active antennas, RF bridge and probes, Mic equalizers and other amateur radio accessories

A Morse code TEXT-to-MIDI converter that creates a Morse code standard MIDI file from ASCII text.

Ground Plane antennas and common mode

Round-Up of different HF Upconverters for RTLSDR by KF7LZE

Limiting static surges on dipoles, verticals or end fed antennas

A well-known transverter modified for 10 MHz IF (for Softrock interface use) by DF9CY

Antenna for limited space, made from 24AWG wire helically wrapped around the top element of a 3-element cane pole, is basically a fully-loaded vertical and performance are limited and should represent the last resort for extreme cases.

Vertical phased antenna systems plans by G3WZT

Dipole, inverted V, full wave loop and grond plane antenna quick reference plans

An effective multiband HF Vertical antenna, used as remote station antenna. Pictures and review of this vertical HF antenna by VK5SW

Modeling small 160 meter antennas, with a focus on the vertical H antenna

70 MHz transverter, 4m band, by G3XBM

Article by N6LF on a top band vertical antenna array system

Design of a 40 meter Vertical antenna

NVIS definition at Wikipedia

The resource details the construction of a multiband trap-style Inverted-V antenna designed for operation on 3.5 MHz, 7 MHz, 14 MHz, 21 MHz, and 28 MHz. It presents specific winding data for the traps, including the number of turns, wire gauge, and coil former dimensions, crucial for achieving resonance on the target bands. The document provides a parts list and a diagram illustrating the antenna's physical layout and trap placement. It outlines the process for building the traps using PVC pipe formers and specifies the required capacitor values for each trap. The design emphasizes a practical approach to achieving multiband operation with a single feedline, a common goal for HF operators with limited space. The document includes a table with antenna segment lengths for each band, allowing for precise replication of the design. It also offers insights into tuning and adjustment, ensuring the antenna performs optimally across the designated amateur radio bands.

The vertical Double-Zepp 2x7 m is a very simple, effective 8-Band-antenna. The end of the Dipol must be 5-10 m above the ground

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

A web site dedicated to collecting and restoring antique crosley tube raidos. pictures and descriptions of antique crosley tube radios from the twentiew, thirties, forties, and fifties. radio advertising from the twenties, thirties, forties, and fifties. tube box art. links to many antique radio related sites.

Double T Bar Vertical antenna are vertical antenna with cross bars on the top and bottom. These crossbars provide capacitance loading thus reducing the size of the antenna

A magnetic loop antenna for the VHF band, featuring a high gain that can be compared to a quarter wave vertical antenna

W0IPL article on NVIS Antenna

Amplifier repair and conversion, specialize in converting HF amplifiers to operate as monoband amps on 50 MHz

The practice of converting computer server power supplies to make a very high quality high power supply at low cost is attractive. It doesn't normally require any modification to the supply but the hard part is figuring out how to trick them into turning on.

Managed by WA3KEY Featuring the Collins Radio Advertisement Archive

Manufacturer industrial and consumer power supply products including switching power supplies, solar panels, solar charge controllers, inverters.

This article is about a simple vertical end-fed-half-wave wire antenna for 10 meters that can be used in case of restricted space.

Portuguese Antenna dealer, offer also HF Converter Kit for the SDR Fun Cube Dongle and RTL SDR sticks

Extending frequency to FT-290R for transverter use

Assembling the Butternut HF9v HF vertical antenna

The supporting structure is a 15-m-glassfibre mast of DX-Wire. The antenna can be used on all bands from 10 to 40 m.

Pictures and description of a SteppIr vertical antenna setup in a small backyard using DX Engineering radial plates.

A 200 kHz bandwidth digital transmission system for image transfer in the Amateur Service is under development, specifically targeting VHF allocations. John B. Stephensen, KD6OZH, leads this project under an FCC Special Temporary Authority (STA) valid until September 10, 2006, authorizing emissions up to 200 kHz bandwidth in the 50.3-50.8 MHz segment. Current regulations typically limit bandwidths to 20 kHz on VHF amateur bands, making this STA crucial for testing wideband digital modes. The modem, a modified **OFDM** (Orthogonal Frequency Division Multiplexed) unit, was initially tested on the 70-cm band. It splits a high-rate data stream into multiple low-rate subcarriers to mitigate multipath echoes. The system uses a DCP-1 card with a Xilinx XC3S400 FPGA and Oki Semiconductor ML67Q5003 microcontroller. The transmitter, located at 36d 46m 30s N, 119d 46m 22s W, generates 150 WPEP into an 8 dBi gain vertical antenna, while the mobile receiver uses a Ham-stick. Three data formats for 50, 100, and 200 kHz channels are being tested, with encoded data rates of 96, 192, and 384 kbps. Verilog code for the VHF OFDM modem is 95% simulated, with modifications from the UHF version including increased filter coefficient precision and a change from Ungerboeck **TCM** to BICM for improved performance over fading paths. Final tests will involve one-way over-the-air measurements of bit error rates and coverage area.

TSC International produces soft magnetic sheet steel, custom-stamped and heat-treated to achieve optimal electrical characteristics for applications such as motors, generators, linear power supplies, and ballasts. The company's manufacturing process focuses on precise material engineering to meet specific performance requirements in various electrical systems. They also specialize in soft magnetic core materials essential for transformers, chokes, and inductors. These core materials are utilized in power supplies, lighting ballasts, signal conditioning circuits, inverters, and battery chargers, providing critical magnetic properties for efficient energy conversion and signal integrity. Located at 39105 Magnetics Blvd, Wadsworth, IL 60083-0399, TSC International provides contact via sales@tscinternational.com or phone at +1 (0) 847 249 4900, facilitating direct inquiries regarding their magnetic component offerings.

The **136kHz Vertical Antenna** at G3YMC employs a Butternut HF2V structure, standing 10m tall. It integrates a 6.5mH loading coil to achieve resonance, with a matching transformer for impedance adjustment. The antenna's configuration includes top loading via a 12m horizontal wire, enhancing capacitive impedance. Initial measurements indicated a high impedance of around 300 ohms, necessitating a transformer for a 50-ohm match. Despite challenges with ground losses, the vertical antenna has shown improved performance in specific directions, filling nulls present in the previous loop antenna setup. The tuning remains broad, with variations due to environmental factors affecting the matching. Ongoing adjustments and comparisons with the loop antenna will continue to refine its effectiveness.

Modeling compact 160 meter antennas, inverted L, half wave dipoles and linearly loaded dipole