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Amplifier, vacuum tube, receiving beverage loop vertical and transmitting antenna system technical information radiation resistance, EH antenna, noise,receivers, and information on keyclicks.

Types of beverage wires, choose best supports and insulators, multiple antennas at one feedpoint, all well documented with photos and exaustive explanation. This article offers insights on building Beverage antennas for optimal reception. Key takeaways include using strong wire (copperweld or electric fence), proper termination, and a good grounding system (multiple copper rods). The author recommends maximizing antenna length and orienting it towards desired stations. For best results, utilize an antenna tuner and experiment with termination resistors.

This antenna is not a true Windom, but rather an off center fed or OCF dipole works on 8 bands from 80 to 10 meters

a guide to help install arrays

Dispels myth about choke balun winding method

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.

Real 4:1 Transmission Line Balun with Balanced Load

Why a vertical antenna or longwire antenna might require a balun

Mobile antennas, loading coil current, and loaded antennas. efficiency and electrical rules. Loading inductors used in mobile HF antennas.

Occasionally errors are made regarding core selection. This especially includes baluns, where on occasion some very strange ideas surface.

Article about omega and gamma matching, related to bandwidth, loss and component failures, heating and power ratings

One of the most popular Ham-lore rumors is a balun's performance can be tested or evaluated by grabbing the coax and watching for an SWR change. This is probably one of the worse test-rumors circulating

How slinky loaded beverage antennas works, includes eznec models

Learn basic theory on antennas, and notes on homebrewing efficient shortwave antennas

Testing and comparison of traps and trap antennas

A ranking of receiving antennas based on noise being evenly distributed in all directions. These rankings are most accurate in the frequency range of AM broadcast, 160 or 80 meter bands

An analysis of the cebik dipole and other small limited space dipoles fed with open wire ladder line.

Page on amplification topics. From vacuum tubes to various components, discussion on stability and arcin causes.

Article about magnetic loops, construction notes and diagrams

Some antenna manufacturers place baluns at the incorrect location in LPDA arrays, or tell you to route the cable incorrectly. This can cause substantial RFI and all sorts of weird problems like RF into house wiring.

318 and 200 ft insulated towers

One popular rumor or thought is that antenna gain doubles every time we double the number of elements

Receiving Common Mode Noise shows how lack of a balun can contribute to system noise

Many antennas function because of common mode currents, rather than working in spite of them. Two popular examples are CFA and EH antennas. Another recent example, appearing in Antennex's compact antenna articles, is a thick stub "vertical" with no counterpoise.

Lowering an NVIS or N.V.I.S. antenna very close to the ground enhances NVIS operation

About beverage antennas, Enhanced F/B Beverages, Bandwidth of Directivity, arrays. This article describes two phasing systems for Beverage antennas that improve directivity and cancel rearward signals. These systems use lossy elements and require minimal components to achieve broadband performance.

Pictures taken during lifting of a Rohn antnena tower

How test a Balun quality by W8JI

Notes and information about G5RV antenna, analysis of short feed lines and relation with SWR

Let's explore the cubical quad antenna, or quad, and see what it really is and how it really works by w8ji

Some antenna manufacturers place baluns at the incorrect location in LPDA arrays. If we consider what the balun does we can see how the mistake occurs.

Understanding Gain differences, j-pole and end-feed vertical antennas.

How the tube converts DC to RF Power

The magic "T" combiner is a very useful device. It can provide equal voltages, equal current, or equal power to matched or unmatched loads. It is not a magic bullet.

This article explores the claim an amplifier might arc from a parasitic oscillation, damaging capacitors, bandswitches, or other components.

About longwire antennas, technically to be a true longwire an antenna needs to be at least one wavelength long, but common use of the term by Hams is for any random wire length that is end fed.

Ameritron AL80B AL811H AL572 Amplifier Trouble Shooting. Tubes replacement, resistor changes.

Elongated Terminated Loops, usage and details by K9AY Lewallen

The rhombic antenna is often claimed to be an exceptionally good antenna with very high gain. Modelling rhombic antennas

Phased antennas elements use radiated fields from multiple elements to produce nulls.

Common problems and improper operations of Yaesu FL 2100 RF power amplifier

This is the 195-foot tall rotating Rohn 55G tower at W8JI with yagis for 40 20 15 and 6 meter bands.

Receiver tests of some transceivers and receivers including FT-1000, FT-2000, IC-751, IC-756 IC-7800 and TS-870

This resource details the four primary functions of a ground system: lightning energy dispersion, equipment safety, RF return path provision for end-fed antennas, and management of induced RF currents. It clarifies that a ground system's effectiveness varies depending on its specific function, noting that a good lightning ground might not be an effective RF ground. The content emphasizes that proper antenna system design, including baluns and appropriate feedline lengths, often negates the need for an RF station ground to mitigate common mode currents or RFI in the shack. The article quantifies lightning energy, stating its peak is in the dozens or hundreds of kilohertz, with damaging energy extending to hundreds of megahertz, and currents reaching thousands of amperes. It recommends solid, wide, smooth copper surfaces for ground leads to achieve low impedance across a wide frequency range. The author, W8JI, shares practical insights from his station, which includes two 300-ft towers and four 130-ft wire verticals, detailing his use of common point grounds and _DX Engineering RR-8 HD_ antenna switches for lightning protection without coaxial surge protectors. Specific examples of antenna systems prone to common mode current problems are listed, such as random wire antennas without proper feedline lengths and off-center fed dipoles. The text also explains how a ground screen or radial system can reduce local noise sensitivity for vertically polarized antennas by covering the lossy earth.

1500 watts PEP output from a Kenwood TL-922 amplifier requires careful attention to parasitic suppression and component selection to ensure stability and longevity. This resource critically examines common modifications, often based on anecdotal evidence rather than sound engineering principles, that can degrade performance or introduce new issues. It highlights how replacing aged components often gets misattributed to the efficacy of unnecessary modifications, leading to widespread misinformation within the amateur radio community regarding amplifier stability. The article details specific, effective modifications for the TL-922, such as shortening anode-to-chassis and anode-to-grid paths to improve VHF stability and efficiency. It addresses issues like incorrect capacitor types in the tank circuit, inadequate grid grounding, and poor RF sheet metal design, providing practical solutions like adding direct ground connections for the plate tune variable capacitor. The author also discusses proper parasitic suppressor design, emphasizing the importance of lead length and component selection for optimal performance and harmonic suppression, contrasting these with less effective or detrimental 'magical suppression kits'.

Sleeve baluns are normally used at VHF and higher. As a general rule, they are not practical at HF. The balun can be inverted and used as a skirt to form part of the antenna element

Article on tubes and their usage in power amplifiers design. Explain failures of tube in RF power amplifiers, a common problem in the SB-220 SB-221, TL-922 and other amplifiers.

Includes W1BB Stew Perry letters, and a sample QSL cards of dated 1963

Understanding current in loading coils

Ground Plane antennas and common mode