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17-Element Very High Frequency/Ultra High Frequency Log Period Dipole Array

An interesting project of the popular IW3HEV antenna analyzer in and embedded solution by PA3CKR.

Optimizing performances of the end-fed antennas QRP quarterly article

Dimensions for the inverted V antenna from 160 to 2 meters by N6JSX

Optimization tests of the W3EDP multi-band HF wire antenna a popular aerial among QRP enthusiasts because it is light weight and cheap.

A nice loop antenna project for 28 MHz with schematic diagram, construction details and a complete video instruction

A 40 meter NVIS beam antenna by W4NVK

All types of Military Antennas, Law Enforcement Antennas, Mobile Radio Antennas, GPS Antennas, Satellite Antennas, WLAN/Wi-Fi/WiMax Antennas, Cell Phones, TV, HDTV Antennas available and sold

A delta loop antenna for the 4 meter band by GW7AAV

US Antenna manufacturer offering base and mobile antennas for 2 meter, 1.25 meter and 70 cm Amateur Radio GMRS and MURS Citizens Band Radio VHF and UHF Business Band Radio HF, VHF and UHF Scanning

G3TXQ study on coaxial cable demonstrate that it can reduce an element's length by something approaching the Velocity Factor of the cable

Build an effective dipole antenna that needs much less space by adding two loading coils. This online calculator tells you how.

VK3YE magnetic loop antenna plan that cover 7 Mhz to 20 Mhz and shortening loop can work on 21 Mhz.

Deploying robust antenna infrastructure for both fixed and portable operations often requires specialized support structures capable of withstanding environmental stresses while providing optimal radiating element placement. SMC offers a range of solutions, including pneumatic masts and push-up masts, designed to facilitate rapid deployment and reliable long-term support for various antenna types. Their product line encompasses antenna mounts, poles, and complete antenna systems, addressing the critical need for stable and efficient RF communication. The company's offerings extend to HF antennas, including dipoles and _NVIS_ (Near Vertical Incidence Skywave) antennas, which are crucial for short-range regional communications on bands like 80m and 40m. These systems are engineered for durability and performance, ensuring signal integrity across diverse operating conditions. With over **65 years** of experience, SMC has established itself as a global manufacturer in this niche. Their product portfolio also includes antenna support towers, catering to more permanent installations requiring significant height and load capacity for multiple arrays.

A wide band active loop receiving antenna project

An online J-Pole antenna calculator that need just to input the frequency and calculates in inch size of each element

A simple coax dipole antenna for 144 MHz by 9A7PJT

Helix antenna online calculator with match calculator

An RSGB article on end-fed wire antennas and the W3EDP alternative.

A novel approach to contruction of a gamma match.

A homebrewed antenna for 2m handheld radios by TB1BIG

The resource presents a detailed schematic for constructing a dual-band vertical antenna, specifically designed for operation on the 2-meter and 70-centimeter amateur radio bands. It illustrates the physical layout, critical dimensions, and component placement necessary for successful replication. Key elements such as the radiating elements, phasing sections, and feed point are clearly depicted, providing a visual guide for radio amateurs undertaking a homebrew antenna project. The diagram specifies the lengths for the VHF and UHF sections, indicating how these elements are integrated to achieve dual-band functionality from a single coaxial feedline. It also implies the use of common materials readily available to most experimenters, focusing on simplicity and effectiveness in its design. The visual format of a GIF image ensures direct access to the construction details without requiring extensive textual interpretation. This schematic serves as a practical reference for hams interested in building a compact, efficient vertical antenna for local and regional FM communications, offering a proven design for immediate implementation.

The page provides a project for an helical dipole for the 40 meters band, resonating on 7 MHz, created by PY1ZFK based on a design by DL8VO. It includes detailed instructions on building the antenna.

A 2-meter Moxon beam antenna, designed for the _144 MHz_ band, is detailed, originating from a desire to participate in the PW 2m QRP contest. The design, based on a Moxon Rectangle, offers a compact directional solution for VHF portable operations. The author, G0KYA, constructed the antenna using readily available materials like 15mm plastic conduit for the frame and 1.5mm copper wire for the elements. Initial testing with an MFJ-259B antenna analyzer showed a **1.2:1 SWR** at 144.300 MHz, indicating good resonance. The antenna's compact size, approximately 70cm x 40cm, makes it highly suitable for portable QRP work, providing a significant advantage over an omnidirectional vertical. The project includes practical advice on element spacing and construction techniques, emphasizing ease of assembly for field deployment. Field results from a local hilltop demonstrated the Moxon's directional characteristics, allowing for effective nulling of local noise and improved signal reception from specific directions.

A complete guide to magnetic loop antenna construction, with analysis of multi-turn and single-turn magneti loops, and and insight on choosing the optimal capacitor, or homebrewing your own butterfly capacitor

This antenna is designed to be mounted off the side of a tower. Works on 136-153 Mhz range but also on 70 cm band

Iulian Rosu YO3DAC / VA3IUL wire ham radio antenna panoramic with sample drawings

Experiments with spiral dipole antennas. Includes two spiral antenna designs for 20 and 40 meters band by KN9B

A multi-band portable vertical antenna can be built with relatively ordinary components obtained from the local hardware store, including replaceable loading coils

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

Raising large Yagi antennas can be a challenging project. A trolley system will make the job a lot easier

The G7FEK Multi-Band Nested Marconi Antenna, a small, efficient all-band antenna.

Memorandum on the Beverage Wave Antenna for Reception of Frequencies in the 550 - 1500 Kilocycle Band", FCC Report 9.2.1, by Benjamin Wolf and Adolph Andersen

Constructing the QE19 Antenna Launcher

SWR (standing wave ratio), is a measurement of how efficiently your antenna system will radiate the power available from your radio. In simple terms, your radio would like to radiate all of its power, but can only do so if the other components cooperate

The antenna is a VHF side is a 2m moxon, tuned on 145.825 MHz. The driven element of the moxon couples to a driven element for a 5 element 70cms Yagi, tuned on 436.5 MHz.

The skeleton slot antenna design was developed in the UK for TV use soon after WW2. This document describe and adapted version for the 2 meter band

Inspired by Milan OK7GU, the goal is to build an universal antenna controller - for different types of rotor, different motor, encoder

This handy and cheap portable dipole can be folded and backpacked, carried in use, and adjusted to a very wide range of frequencies by KV5R

Configurations of the vertical antenna arrays used at 6Y2A

A switchable Magnetic Transformer for Transmitting for various impedances

The ZS6BKW multiband antenna, an optimized variant of the classic G5RV, features a 102-foot (31.1 m) horizontal span and a 39.1-foot ladder line matching section. This design, derived by G0GSF (formerly ZS6BKW) in the early 1980s using computer programs and _Smith charts_, aims for improved SWR across multiple HF bands compared to its predecessor. Construction details specify Wireman 554 ladder line and #14 AWG THHN copper wire for the radiators, with precise instructions for determining the velocity factor (VF) of the ladder line using an antenna analyzer or dip meter, ensuring accurate physical length for the matching section. The radiator length is electrically 1.35 wavelengths for the 20-meter band, requiring careful trimming during tuning. Field measurements with an _AIM-4170C_ analyzer by KI4PMI and NC4FB demonstrated good SWR curves and bandwidth on 6, 10, 12, 17, 20, and 40 meters. The antenna was deemed unusable on 15 and 30 meters due to very high SWR, but an LDG AT-100PRO autotuner successfully brought 6 and 80 meters into tune. Contacts were made on 80, 40, 20, and 17 meters, including a **17-meter** contact to Spain. EZNEC models for 80-6 meters are provided, along with an AutoEZ model by AC6LA, which predicted good SWR for 80-10 meters. W5DXP's modifications for an all-band HF ZS6BKW are also referenced.

A monster magnetic loop antenna for 160 meters band. This Magnetic loop is optimized for 1840 Khz + 50 Khz. PDF Article published on La Radiospecola 10.22

The EggBeater Antenna web page by ON6WG F5VIF a web site dedicate to this VHF UHF antenna

This is a plan for a 10 elements yagi antenna for 50 mhz

A Variable Base-Loading-Coil provides a practical solution for optimizing HF mobile whip performance across multiple bands. The design, as presented by VK4ADC, details a coil wound on a 50mm PVC former, utilizing 1.6mm enamelled copper wire for robust construction. This approach allows for precise tuning, a critical factor in achieving efficient radiation from a mobile setup, where antenna length is often compromised. My own field experience with similar base-loaded whips confirms the importance of a well-designed loading coil for maximizing signal strength and minimizing SWR. The VK4ADC design incorporates a sliding contact, enabling continuous adjustment, which is superior to fixed taps for fine-tuning resonance on the fly. This variable inductance allows the operator to quickly adapt the antenna to different HF segments, from 80 meters up to 10 meters, without needing to swap out multiple coils. The document includes specific winding data, such as the number of turns per inch and the overall length of the coil, which are essential for replication. It also touches upon the mechanical aspects of integrating the coil with a standard mobile whip, ensuring a stable and weather-resistant assembly for reliable operation during mobile DXing or casual rag-chewing.

Italian web site describing a project for a 2 meters home made halo antenna

The original project of a dual band yagi antenna for 50 and 70 mhz, published on dubus 2/2007 by YU7EF

This modification will allow the use of separate receive and transmit antennas on the Kenwood TS-850S/AT.

Operating on the 2200m band (135.7-137.8 kHz) often presents challenges for amateur radio transceivers, which typically exhibit poor receiver performance at these very low frequencies. This project addresses the issue by providing a design for a dedicated 137 kHz antenna preamplifier, specifically tailored to improve signal reception for radios such as the _Yaesu FT-817_. The preamplifier circuit utilizes a low-noise FET input stage, crucial for minimizing self-generated noise and maximizing the signal-to-noise ratio from weak LF signals. The design includes a detailed schematic, component values, and construction notes, enabling homebrewers to build a functional unit. The goal is to achieve significant gain, making the faint signals on 2200m more discernible and improving overall band usability. Key design considerations include impedance matching to typical antenna systems and ensuring stable operation across the narrow LF segment. The circuit aims for a **low noise figure** and sufficient amplification to overcome the inherent limitations of general-purpose HF transceivers when operating below **200 kHz**.