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With all the wire you have out, you may run into a problem with static buildup on the antennas. This static may try to make its way into your receiver, causing you major problems and damage that can run into a lot of money.

The page discusses the concept of a 2-element Parasitic Ground Plane antenna for the 40-meter band. It includes a conversation between amateur radio operators discussing modeling results and design considerations for the antenna. The author shares insights on radial configurations and the impact on antenna efficiency and pattern.

Buy plastic sheet, plastic rod, plastic tubing, bar, tube and plastic film from professional plastics. buy plastic materials online

Magnetic Loop Antenna for 20/15m with Remote Tuning by George Szymanski

Here is a simple, self-contained beacon which can run a few milliwatts or as much as a watt depending on choice of amplifier and supply voltage.

Article by N6LF on a top band vertical antenna array system

Design of a 40 meter Vertical antenna

Schematic diagram and description of a magnetic loop antenna that works from 10 to 20 meters band, made from junk

Review of the Kenwood TS 830

Article on ham radio mobile operation from Andy D. Crouch N5NDD

NVIS definition at Wikipedia

Errante's virtual ground Balun, a state-of-the-art high power HF balun family.

Accurate calibration of your receiver and sound card is necessary for good results with the weak signal modes in use at LF. Modern receivers with master oscillators that are synthesized to provide all conversion frequencies greatly simplify the process. This article describes a method of making the necessary measurements and adjustments to an ICOM R75 receiver and a sound card, using the ARGO software

A personal review about the Yaesu FT-817

The early 20th century saw significant advancements in wireless communication, culminating in the first successful transatlantic radio signal. This historical account details Guglielmo Marconi's pioneering efforts, from his initial experiments with electromagnetic waves to his patented wireless system in 1900. It describes the technical challenges of long-distance radio transmission, particularly the prevailing belief that radio waves would be lost due to the Earth's curvature over vast distances. On December 12, 1901, Marconi established a receiving station in Newfoundland, Canada, utilizing a _coherer_ and balloons to elevate the antenna. Signals, consisting of the Morse code letter "S" (pip-pip-pip), were transmitted from Poldhu, Cornwall, England. The successful reception of these faint but distinct signals across **1,700 miles** confirmed Marconi's theories, marking an epoch in communication history. This achievement demonstrated the viability of global wireless communication, paving the way for future developments in radio technology.

All about dipole antenna construction

Operating magnetic loop antennas requires careful consideration of RF safety, particularly regarding near-field magnetic field intensity. This resource presents calculations for magnetic field strength (H-field) at various distances from a magnetic loop, emphasizing that the H-field is significantly higher than the E-field in the near-field region due to the inductive nature of the radiating element. It provides specific formulas and examples for determining safe operating distances based on power levels and loop dimensions, crucial for compliance with RF exposure limits. The analysis compares calculated H-field values against FCC and ICNIRP maximum permissible exposure (MPE) limits for controlled and uncontrolled environments. It demonstrates that even at QRP power levels (e.g., 5W), the H-field can exceed MPE limits within a few feet of the antenna, necessitating greater separation distances than often assumed for electric field considerations. The practical application of these calculations helps amateur radio operators configure their stations to ensure personnel safety and regulatory compliance when deploying compact, high-Q magnetic loop antennas.

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

Testing performances of indoor antenna. A comparison of a magnetic loop antenna vs a classic wire dipole done using wsprlite on 30 meters band.

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

Discussion at eham about wire size used in wire antennas, and how it affects the gain of the antenna

A complete EmComm portable station article on eham.net by K9RFZ

Adam Brown's Blog from Latitude 80.19 South Longitude 81.16 West

Interesting article on how and when sleep during a contest

Experimental Dual Band High Gain Flower Pot Antenna

A NEC Model Comparative Analysis of Physical Orientation and Performance. The small magnetic loop is a useful compromise antenna for limited space and portability. For this reason, the magnetic loop antenna is a practical high frequency antenna solution for the restricted space of apartment dwellers

For radio amateurs and electronics enthusiasts requiring specialized wiring solutions, Multi/Cable Corporation provides custom multi-conductor cable manufacturing services. They focus on made-to-order constructions, offering a broad range of specialty cable products including composite, instrumentation, electronic, flexible cord, thermocouple, high-temperature, and Mil-Spec wire and cable. Their capabilities extend to extensive customization of all cable components, ensuring precise adaptation to specific application requirements, which can be critical for bespoke shack setups or antenna control lines. With over 50 years in business, Multi/Cable emphasizes low minimum orders, quick turnarounds, and competitive pricing, making custom cable solutions accessible even for smaller projects. A case study highlights their role in helping an emergency vehicle lighting company expand offerings by providing versatile and cost-effective wire bundles, demonstrating their ability to support diverse technical needs beyond typical off-the-shelf options. They also provide reference data and guides on choosing conductors, insulation, and jacketing materials.

75m Mobile Texas Bugcatcher Loading Coil Measurements

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

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.

Operating practice in english

Experimentig magnetic loop antennas for VHF and HF by M0UKD

W4TI Rotator Installation

Sensitivity of multi turn receiving loops William E. Payne, N4YWK

An excel spreadsheet that in a really simple way checks how much to trim your antenna elements. Download the xls file and watch the presentation video include in this page

AM DXing taken to the extreme. Reports and station logs from DXpeditions to Arctic Northern Finland. Also articles, QSL news, links, audio and video on AM DXing. Published by Finnish DXer Mika Mikelainen.

The configuration of this antenna is a triangle with apex in the top of a very tall tree. The antenna is fed at a bottom corner using 450 ohm ladder line.

The advantage of 5/8 wave antenna is that it has the lowest angle of radiation and has about 1dB more gain when compared to 1/4 and 1/2 verticals. So the 5/8 should be the favourite choice for DX.

ECARA is a non-profit organization dedicated to the public service and promotion of amateur radio, and is affilated with the American Radio Relay League.

Review of Logikey K-5 Keyer

A vertical antenna project for the 7MHz made with some spare parts. Based on a broken 20 foot fishing pole, it is based on a good ground system made with radials and a capacitive hat done to increase the global radiation resistance of the antenna. A custom loading coil is also included in this project to perfectly tune the antenna to the CW portion of the 40 meters band.

Technical Correspondence, QST, July 1990 - Why even "perfect" phased array element currents don't produce perfect patterns.

Getting the most out of LowFER transmitting antennas, designing an efficient antenna for the 1750-meter band by K0LR

Experimenting vertical wire antennas for 40 and 20 meters supported by balloons resulting in excellent gain in RX and good overall performance against horizontal dipole

The **Solarcon A99** vertical antenna, a half-wave over a quarter-wave variable mutual inductance design, primarily serves the 11-meter CB band but also finds use on 10 and 12 meters for amateur radio operators. Its simple construction, consisting of three fiberglass sections and a 16 AWG radiating element, makes it an accessible option for new operators or those seeking an easy-to-install base station antenna without complex mounting requirements. Despite claims of 9.9 dBi gain being widely considered exaggerated, and a manufacturer rating of 2000 watts power handling often viewed with skepticism (with 300 watts suggested as a practical limit), the A99 maintains popularity due to its low cost and ease of deployment. It typically tunes to a 1.2-1.3 SWR out of the box, requiring minimal adjustment via its two tuning rings. Its high angle of radiation allows for effective local communication even when mounted at low heights, such as 8-10 feet off the ground. However, the A99 is known for significant RF bleed-over issues, particularly when operated with higher power or mounted close to residential electronics. While its internal design is often described as cheap, the antenna exhibits remarkable durability, frequently lasting a decade or more in various weather conditions. Its affordability and straightforward setup continue to make it a go-to choice for many radio enthusiasts.

A simple morse code practice oscillator using either PNP or NPN typr transistors

Understanding Solid State Linear Amplifiers