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Operating in a Single Operator Two Radios (SO2R) setup, especially with beverage antennas, often exposes the receiving radio's front-end to significant RF energy from the transmitting radio. This resource details a practical, homebrew receiver protection circuit designed to mitigate this risk. The core of the design involves a non-inductive 2W 22 Ohm carbon composition resistor in series with the RX antenna line, followed by two stacks of four fast-switching diodes (e.g., _1N914_) configured in opposite polarizations. This arrangement effectively clamps the incoming voltage to approximately 2.8 V peak-to-peak, safeguarding sensitive receiver input components. The series resistor plays a crucial role by absorbing excess power, preventing the diodes from exceeding their current ratings and potentially failing open, which would leave the receiver unprotected. The author, _N4KG_, measured up to 50 watts of coupled power between 80M slopers on the same tower, highlighting the necessity of such protection. The design is presented as a cost-effective solution to prevent damage to receiver input transformers, with the author noting successful protection of a receiver even after a resistor showed signs of overheating. This simple circuit can be integrated via a transverter plug, offering a robust defense against high RF input.

Stacking yagi antennas for 50 Mhz band article by by Zaba, OH1ZAA/NN0Y

A collection of 450 MHz Cheap Yagis that have proven great portable operations, back-packing and transmitter hunts, and are something inexpensive you can throw up in the attic for that weak repeater

This presentation applies to HF / VHF / UHF antennas and is about 14 different type of antennas suitable for indoor od apartament installations

Learn how to build a simple 12vdc azimuth and elevation motor unit for the Arrow Satellite Antenna to improve your FM satellite communication experience. This DIY project involves using a camera tripod and basic materials like aluminum tube and standoffs. Get detailed instructions, including the gearhead motor product number for optimal performance. Discover where to purchase the necessary components and stay updated on alternative motor options. Enhance your ham radio operations with this homemade rotator setup, designed for easy satellite tracking and communication. Share feedback and connect with other radio enthusiasts for more tips and ideas.

Ultimax antennas manufacturer of amateur radio End-Fed and bazooka antennas made in USA

This page describes an entirely simple, One-Knob matchbox that will match this antenna efficiently on 40, 30 and 20m, using a simple circuit that can be switched between series-resonant and parallel-resonant with just one banana jumper

An FCP is not magic. It has no gain. An FCP improves an antenna system by replacing more loss with less loss. Some have been able to erect better wires in the air because the small size of the FCP allowed better placement of the antenna.

If You are using a separate receive antennas then you need a good protection circuit to eliminate the possibility of blowing out the receiver front-end while using these auxiliary receive antennas specially on low bands.

A cavity backed antenna is a practical slot antenna tipically used in microwave applications

Analysis of flag receiving antennas using MININEC with focus on relation of size and atenna height by VE6WZ

This PDF guide provides detailed instructions and diagrams for constructing a fan dipole antenna, a popular choice among hams for multiband operations. The guide covers the design, materials needed, and installation process, offering step-by-step guidance to help hams set up an effective antenna system for their radio operations.

Experiments on vertical antennas for HF bands.

On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.

Examines various low-band receiving antennas, including the Beverage, Pennant, Flag, and Quad, specifically for deployment in noisy city environments. The resource provides a semi-scientific analysis of common receiving antenna types, focusing on their performance characteristics and practical considerations for urban settings. It details construction parameters for each antenna, such as the use of 9:1 baluns and 300-500 Ohm terminating resistors, and discusses the necessity of preamplifiers for certain configurations. Specific deployment advice includes avoiding radial fields to minimize noise pickup and methods for temporary wire antenna installations. The document provides antenna dimensions, noting a full-size Quad requires 540 feet of wire. Performance observations highlight a Quad variant used by N0XA (AB0X) that achieved 160M CQ WW records and facilitated over 120 JA contacts without a preamp.

High-performance rugged antennas and RF accessories such as magnetic mounts, RF coaxial gooseneck adapters, LNAs, BDCs, for law enforcment, military, maritime and video markets.

Antennas custom made to your frequency of choice

Construction tips of a basic wire antenna, the half wave dipole. Inverted V dipoles and effects of inverted v on radiation pattern.

This active antenna for the shortwave band provides surprising performance, even indoors. As the name implies, the main loop is made from a Hula-Hoop with the metallic paint stripped off and a single turn of 14AWG copper wire inserted inside the hoop.

Vertical end fed antenna used for portable operations. The antenna will work on 80 with acceptable results, it will work fine on 40m, and it will be a good deal better than a normal 1/4 wave GP on 20, 17, 15 meters.

This is a very small vertical 160m antenna that fits in the loft of even my small house. It was built as a way of getting a signal out on 160m for local AM contacts, but the local noise level was far too high to allow it to be used at night for this purpose. However, on WSPR it did a pretty good job with WSPR spots from a very long way across Europe being received when running 2.5W out.

The collinear J-Pole, often known as the Super-J, does improve the behavior over a regular J-Pole. there is an advantage when vertically combining 1/2 radiating sections to have a bit of separation between the half-wave end points. Get 0.8 dB more gain out of the trusty Super-J by replacing the traditional phasing stub with a long coil.

A small active voltage probe antenna to aid reception on the LF bands

Dipole antennas, vertical half-wave dipole antennas with impedence tranformes that can be used for portable operations. Some well worn antenna configurations are the easiest and loudest lash-ups you can try.

The original HEXBEAM was developed by Mike Traffic, N1HXA, in the early nineties. It is true that an M over W configured yagi antenna that resembled a butterfly was earlier tried successfully. But the advanced electrical design, the characteristic nesting concept and central terminal post that enable the multi band functionality along with the basic hardware design were all developed by Mike Traffie.

Coax Velocity Factor in Baluns, Does it Matter? Test results show coaxial cable velocity factor does not always enter into stub length calculations especially in the world of Baluns

Experimental Long Boom Antennas - CP, LPDA, multiband with several NEC Files for 50MHz 144MHz 222 MHz 432MHz but also 902MHz and 1296 MHz Antenna projects. Includes also for each antenna model, in a general comparison table each antenna characteristics including Directive Gain, G/T, E-F/R, H-F/R abd Boom Length. This is a great value comparison table of several commercial and home made VHF UHF antenna projects.

This document provides a detailed guide on constructing and mounting a folded dipol for the 146 MHz frequency in a vertical configuration to be used in Yagi antennas. The step-by-step instructions and diagrams included make it easy for hams to build and set up this type of antenna. Understanding and implementing this design can enhance the performance of radio communication for Amateurs operating in the 2-meter band. Whether you are looking to improve your signal strength or experiment with antenna designs, this resource offers valuable insights and practical information.

Hy-Gain TH3jr Tri-band HF 3 Element Beam Covers 10, 15 and 20 Meters assembly instruction manual

An article about the Beverage antennas, super long wire receiving antennas thar are unidirectional and have a very low noise that makes this antenna excellent for low band dxing. By Thomas R. Sundstrom W2XQ, 73, June 1981, 73 Magazine

This page presents an online calculator tool for determining the dimensions of various HF wire antennas operating between 1.8-30 MHz. Users input their desired resonant frequency to obtain precise measurements for four popular antenna types: standard flat-top dipole, inverted Vee, quad loop, and equilateral delta loop. The calculator provides comprehensive measurements including leg lengths, minimum heights, horizontal spreads, and feedpoint distances. Accompanying the calculator are detailed technical explanations, construction notes, and installation guidelines for each antenna type, making it a practical resource for amateur radio operators building their own antennas.

What is antenna polarization, and why does it matter. Horizontal versus Vertical versus Circular polarization. Undestanding how antennas perform better with different polarizations.

A comparison among a traditional J-Pole Antenna and 2BCX Slim Jim Antenna

Operating marine mobile with antennas for 15-17-20 meters band.

HF Antennas is a division of Comsystems Solutions we manufacture wire broadband antennas and different type.

Experimentin wire antennas on top band using several type of aerials. This includes a 40 to 160 meters EndFed Half Wave kite antennas and 160m/80m loaded vertical antenna.

This project focuses on testing and comparing various antennas for receiving ADS-B (Automatic Dependent Surveillance-Broadcast) signals, utilizing software tools like RTL1090 and Virtual Radar with an RTL-SDR dongle. The goal is to evaluate the reception range ("ReceiverRange") and performance of different antenna types when tracking aircraft signals, particularly around the Amersfoort area. The project includes a comprehensive photo album documenting the antenna designs and setup processes, serving as a valuable resource for enthusiasts building ADS-B reception systems

Antenna most often used by Hams around the world. Inexpensive, effective and easy to build, what more could anyone ask for in a home made antenna.

A dual band 40-80 vertical antenna on an 18m Spiderbeam Fiberglass Spiderpole, with monoband performance

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

An Inverted-L with its long leg sloping to the ground. It will still work very good, even if the horizontal wire has to be sloped diagonally to the ground, as long as you have enough horizontal space to keep it at about a 45 degree angle or more from the pole.

This document details the construction of a multi-band end-fed antenna, suitable for situations with limited space for larger antennas. The design utilizes a 1:49 to 1:60 impedance transformer to match a half-wave wire antenna fed at one end. Compared to a traditional dipole, this antenna resembles a highly unbalanced Windom antenna with one very long leg and a virtual short leg. The design eliminates the need for radials but relies on the coax cable shield for grounding. The document recommends using at least 10 meters of coax and installing a common mode filter at the entry point to the shack for improved performance.

Dipole for 40m band. It is a simple linear loaded dipole feeded with 450-Ohm openwire feedline. Designed it for resonance at 7.050 MHz, can be tuned on 30m and 80m bands with an external antenna tuner. Build with simple electrical copper wire (2.5 mmq/13 awg) and two fishing poles with size of about 7 m/23 ft.

Magnetic loop receive antennas manufacturer. W6LVP loops cover 2200 through 10 meters (135 kHz through 30 MHz) with no tuning or adjustment.

144MHz 2m Portable Yagi VHF Beam Antenna. This page contains construction details on a 2 metre 144MHz VHF Yagi beam antenna, designed for portable use.

This is a FULL SIZE quarter-wavelength vertical made on a 18m Spiderbeam fiberglass telescoping Spiderpole

A 14.12 dBi gain three elements cubical quad antenna for the six meters band. This Quad Antenna design page include a MMA model available to download and dimensions for each element.

In this article the author describes his personal experience on some antennas for 50 MHz he tested on the field, the six meter Dipole, Vertical, Moxon, a 3 element Yagi and an Omniangle antenna.

This is very common W7IUV Flag Antenna design is based on the PY3AGD antenna because it uses the antenna mounted horizontally and nd it is perfect for my small city lot installation.