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Shortened dipole with traps for 40 meters band in portuguese

Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.

The total length of the inverted L is 240 feet, which is 7/16th of a wave length long. It has a 92 foot horizontal linear load section 1 foot above ground that terminates into a home-brewed parallel network tuner by KN4LF

Forum thread about possibility to extend VX-6R to freeband and 6 meters

40 meter transmitter by K9GDT

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.

Details a practical QRP wattmeter construction, leveraging a simplified SWR meter design by JA6HIC. The project focuses on a forward-only power measurement circuit, providing a functional instrument for RF power levels from milliwatts up to 5 watts. It maintains a 50-ohm input and output impedance, suitable for typical QRP transceivers and antenna systems. The resource includes the schematic for the "VSW" (Very Simple Wattmeter) and outlines a six-step alignment procedure. This calibration process involves using a known RF source up to 5W, setting full-scale deflection, and marking power increments. It also addresses minimizing frequency effects on readings with a 100pF trimmer capacitor, noting that measurement error is highest at the lower end of the scale. Construction notes mention using a piece of RG-213 coaxial cable for the inductance and coupler, with the wattmeter assembled in early 2003. The author provides an example measurement showing 0.8W into a dummy load and 1W into a 3-element beam.

BesserNet Reflectometer is a fun SWR calculator and simulator Java applet

A Moxon rectangle antenna for 17 and 20 meters band

VK2ZAY end-fed antenna for 40 and 80 meter band

G3YCC article pn the W3EDP end-fed antenna for 80 to 20 meters bands

2 meter or Dual Band J-pole bicycle antenna

Elelement yagi beam antenna for 2 meters band by ON6MU

If you find external wire antennas obtrusive for amateur radio or short wave listening, then this is the antenna for you, is just 1 meter diameter

2 Element Cubical Quad Antenna for 28 MHz by DL7JV in german

This is a resonant, half-wave, vertical antenna. It takes up little space in the back yard, was designed for operation on a single frequency 80 meter PSK net, and is reasonably inexpensive to construct by Chuck Hines, K6QKL

Faqs on six meters band, designed to help encourage hams to use and enjoy this band

The 40/60/80 is a portable loop that covers 80 meters with a high degree of compromise

Smith is a professional Computer Smith-Chart Tool and S-Parameter Plot for windows, special price for hams and students by Fritz Dellsperger

This little antenna is cheap and easy to build, lightweight, and very functional on 2 meters and 70 centimeters by NA4IT

Pictures and circuit diagramm to build this power amplifier for 2 meters

KC22TX receiving loop antenna for 160 meter band

Pictures and calculated values for this home made magnetic loop antenna for the 160 meters band by HB9MTN

The article "Exploring the World of 10 Meter Beacons" by Ken Reitz, KS4ZR, provides an in-depth look at 10-meter beacon operations, focusing on their utility for propagation analysis. It details FCC Rules part 97.203 governing beacon stations, including license requirements, power limits (under 100 watts), and the specified band segment of 28.200-28.300 MHz for U.S. operations. The content highlights the diversity in beacon construction, from converted CB radios to home-brew QRP transmitters, and discusses the robust operating conditions these 24/7 stations endure. The resource presents several case studies of active 10-meter beacon operators like Ron Anderson KA0PSE/B, Domenic Bianco KC9GNK/B, and Bill Hays WJ5O/B, detailing their equipment, antenna setups, and typical signal report volumes. It also introduces the NCDXF/IARU International Beacon Project, which features 18 synchronized beacons worldwide transmitting on 28.200 MHz at varying power levels (100W, 10W, 1W, 100mW) to facilitate propagation testing. The article also covers the PropNet Project utilizing PSK31 on 28.131 MHz and the 250 Synchronized Propagation Beacon Project on 28.250 MHz. Practical advice for monitoring includes using the RST reporting method, understanding the impact of the solar cycle on 10-meter propagation, and tips for setting up a personal beacon, such as frequency selection and power output considerations. The IY4M Guglielmo Marconi Memorial Beacon Robot on 28.195 MHz is also mentioned for its automatic QSO mode. The article concludes with a list of other resources for 10-meter beacon information.

DL2HRF shortened dipole antenna for 80 meters band

Homebrewed jpole antenna for 50 mhz by IW0BZD, include pictures and schematics, in italian.

Add some gain over your rubber dummy load with this full size dipole on your HT.

Homebrew with CF300 DGMF with about .24 dBD gain

2 meters band VHF dipole with gamma match system

Article on the HF dual band antenna with construction details and how to add 160 meters to the HF2V

Homebrew a vertical antenna for 40 and 80 meters band based on popular HF2V model by DL7JV

1/2wave vertical antenna for the 6-meterband and a 5/8 ground plane antenna for 50 Mhz

VE7CA experiments on 160 meters band antennas, looking for better performances on reception.

VU2RAR basic VHF power amplifier suitable for 144-146 Mhz output power can vary from 3 to 25 Watts.

Constructing a compact, two-band magnetic loop antenna for HF operation, especially from constrained locations like a balcony, presents unique challenges. OK1FOU's design, inspired by DJ3RW's 50 MHz loop, addresses these by employing an unusual side-fed configuration and placing the symmetric, two-section variable tuning capacitor at the bottom of the loop, directly connected to the coax shield. The article provides specific material recommendations, including two 1-meter wooden pales and about 3 meters of thick loudspeaker cable, noting the high current (60A at 100W) in the loop. Construction steps detail forming two turns with a 5 cm gap, using a GDO to pre-tune the open loop to a frequency slightly above the desired highest band, and then integrating the tuning and coupling capacitors. For 10/14 MHz, an open loop resonance of 16-17 MHz is suggested. Practical experience with the 10 MHz band from a third-floor balcony in Prague (JO70GC) shows a 1:1 SWR across most of the band without an external ATU. While DX traffic was modest due to the urban environment, QSO examples with RA6WF, LA6GIA, G0NXA, and LZ1QK on 10 MHz are provided, demonstrating its operational capability.

A vertical antenna for 40 and 80 meters band with no need of antenna tuner, based on a telescopic fiberglass mast of 48 feet by N8NSN

Based on the N2PK design, this swr meter use a stockton directional coupler

This is a simple calculator for solving the antenna wire catenary between to end points given the design wind speed, mass per unit length of the wire, wire diameter and Gross Breaking Strength of the wire.

A table with Loss in DB/100m , Max power in Watts, Diameter in mm , Velocity factor (VF) expecially in VHF UHF and Microwave

Thermocouple ammeters are very rare these days, but the job they were perfect for - measuring antenna currents - is still a modern requirement especially in respect to groundplane currents. By David A. Reid PA3HBB G0BZF

VHF Optimized Yagi Antenna for the 6-meter band (50 Mhz) by ON6MU

FindU.com operates as a robust database archiving **APRS** (Automatic Packet Reporting System) data, including weather, position, telemetry, and message reports. It integrates data from both amateur radio APRS systems and the internet-based Citizen Weather Observer Program. This substantial 58 GB database is hosted on dual servers utilizing data replication, processing approximately 20 new reports per second to provide constantly updated information. The system supports various applications, such as displaying weather reports, tracking position data, and facilitating long-term vehicle tracking. A notable function involves forwarding over 100,000 near-realtime weather observations daily to the National Oceanographic and Atmospheric Administration (NOAA) for accuracy checks and use by NOAA and the National Weather Service. Additionally, it archives APRS reports from the International Space Station. Access to the database is primarily via dynamic web pages, with a comprehensive list of available CGIs detailed on a dedicated server page. While direct URL parameter editing is possible for advanced users, alternative web pages with forms simplify query submission. The platform utilizes **PNG** images for dynamic graphics, a choice made due to past GIF patent issues, ensuring broad browser compatibility.

3 Band vertical Marconi-antenna for the bands 40, 80, 160 meters with a ground net of wires as radials.

A 5/8 vertical groundplane antenna for 50 mhz

A schematic design of the W3DZZ antenna in portugues with description of trap building

A portable VHF home-made Yagi-Uda antenna, that is extremely easy to build and very cheap. Moreover this antenna, while dismounted is just 1 meter long, and the total weight is just 100 grams.

A mobile antenna for the 75 meters band by K0RWU

A well documented article on a small magnetic loop antenna for the 40 meters band

The 2 meters version of the HB9RU antenna in german

Presents the detailed construction of the _FLA25HV_ antenna, a specialized array optimized for Earth-Moon-Earth (EME) communications on the 2-meter band. This resource provides schematics and practical insights into building a high-gain antenna system capable of reflecting signals off the lunar surface, a challenging but rewarding aspect of amateur radio. It covers the mechanical and electrical considerations essential for achieving the precise pointing and signal strength required for successful moonbounce contacts, often yielding **20 dB** or more gain. Amateur radio operators pursuing EME operations require robust antenna systems and precise tracking capabilities. The FLA25HV design addresses these needs by focusing on element spacing, impedance matching, and structural integrity to withstand environmental factors while maintaining critical alignment for lunar reflections. Such systems are crucial for making contacts over distances exceeding **768,000 km**. This personal page serves as a practical guide for hams interested in constructing their own EME arrays, offering a glimpse into the technical dedication involved in pushing the boundaries of VHF/UHF propagation.