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Low Noise Antenna pre-amp for SAT, EME & DX-ing

IC706 Specifications by universal radio inc

Different band dipoles can be put together with a single feed, learn how by W8HDU

Live feed from Warren county fire dep. radio

Homemade HF Tuner by PE1OPM

Build an HF antenna tuner by VK5AJL

An RF power supply for 144 MHz schematics and instructions

The NAVTEX system is used for the automatic broadcast of localised Maritime Safety Information (MSI) using Radio Telex (also known as Narrow Band Direct Printing, or NBDP).

A compact Quad Antenna for the HF Bands by GM0ONX

High Voltage Supply for GS 35B Amplifier

A folded wire antenna for 160 meters as appeared on 73 amateur radio magazine june 1997

by USCG navigation center

A pdf file with review of RTTY contests software available on the net and information on how to operate a RTTY Contest, by RSGB.

Operational testing of a 10.07-meter portable HF vertical antenna, constructed from telescoping aluminum tubing (36, 32, 22, 17 mm diameters), yielded SWR measurements below 1.5 across multiple bands. Initial trials on 14.150 MHz showed an SWR of 1.6, while 7.075 MHz was problematic. Subsequent adjustments, including a 13 cm extension to the radiating element, improved performance, enabling operation on 6, 15, and 40 meters without a balun, and adding 12 meters with a balun. The design prioritizes portability, allowing transport in a standard vehicle and single-person deployment. Four 10.07-meter radials are connected at the base to enhance ground plane effectiveness. The article details the mechanical assembly, including custom adapters for tube transitions and a PVC sanitary tube sleeve for base insulation, ensuring robust field deployment. Final SWR measurements, documented with an _MFJ-259_ antenna analyzer, confirm operational ranges: 6.800-7.500 MHz (SWR < 1.5), 20.800-22.500 MHz (SWR < 1.5), and 48.800-51.500 MHz (SWR < 1.5) without a balun. With a balun, the antenna achieved SWR < 1.5 on 13.750-15.000 MHz and 24.890-28.350 MHz, demonstrating its versatility for portable _DXpeditions_.

Low power VHF RF amplifier with VMP1 Mosfet by IZ1BTS IK1XPD

ARRL comparison of HF transceivers, including Elekraft, TenTec,Icom, Yaesu and Kenwood recent transceivers based on QST product reviews

This program displays solar-terrestrial data for radio waves propagation that is provided by the N0NBH web-service.

This project was published in the April 2004 issue of the Australian magazine Amateur Radio, and has been designed using parts which are very readily available.

IC&#8208;2300 MARS/CAP mod expanded frequency range 136&#8208;174 MHz

Diagram and sample ferrite balaun for 1.8-30 MHz

Ari Milano draw and keep updated these pdf files representing the "radioamatori" bandplan, with notes in italian

Plans and drawings of common amateur radio antennas, like jpoles, copper cactus, super jpole, omnidirectionals and quads

All Band HF Doublet for operation over all HF bands including 160m.

A 67 feet long dipole doublet antenna

Planning and modelling Delta Loop antennas for all the ham radio HF bands include calculated wire lengths at each mid-band

Transverter for 70MHz, a project by G3XBM

Working priciple of OSJ and jpole anntennas by PY4ZBZ

Fractal antenna for 28 Mhz band by AG1LE

A multiband quarter wave vertical antenna that works on 5 bands.

A VHF power amplifier made with two cheap RF transistors, 2N3924 as driver and a BFS22A for final stage, giving an unexpected output power of 7-8 watts maximum

A comprehensive guide to receive Weather Satellites signals in wefax mode

The page discusses Axial-Mode Helical Antennas, focusing on turning helical antennas over perfect ground and modeling helices in NEC-2 for optimized design. It covers topics such as high-gain performance, broadband, impedance matching, radiation pattern, feedline, balun, near field, far field, and DIY applications.

Yaesu FT-857 features and specifications

The aim of the project is test if fractal antennas can work acceptably on HF bands.

The problem with making your own trapped HF antennas is usually getting the coaxial traps tuned to frequency.

About HF Wire Antennas for field day or any day a basic wire antenna article

Demonstrates the product line of _LZ Antenna Ltd._, a Bulgarian manufacturer specializing in amateur radio antennas and custom electronic devices. The company focuses on robust, high-quality HF multiband Yagi and vertical antennas, leveraging over 20 years of experience from founder Georgi Georgiev in radio amateur development. Featured models include the LZA 8-4, LZA-10-3, and the LZA-7-3A WRTC 2022, alongside various rotary dipoles like the LZA1 40/30m. Provides specifications for several Yagi antennas, such as the LZA-9-5, LZA-13-7, and LZA-6-3 (a 6-element, 3-band design). The company emphasizes applying "leading edge technology" to high-frequency communication equipment production, with products designed for durability and performance. The LZA-10-5 Yagi offers **12.5 dBi** gain on 10m, while the LZA-13-7 provides **13.2 dBi** on 20m, showcasing competitive gain figures for DXing and contesting.

The HF ham bands can be mysterious. Some work at night, some during the day. Some seem to be good for long distance contacts while some are better for nearby contacts. Even worse, they change tremendously from hour to hour and day to day. An overview on operating on HF amateur radio bands

A vertical portable antenna system by W0SJS that will work on 40, 30, 20, 17 and 15 meters

By Guy, de ON6MU, At VHF, both the 1/4-wavelength monopole and the 5/8-wavelength monopole antennas are widely used.

Olivia MFSK digital communications are becoming popular in amateur radio because Olivia is one of the most robust methods of text keyboarding, that can perform superbly for long distance communications. Olivia frequencies, format and software

IC-718 tech. specifications

Compact and efficient magnetic loop antenna that cover from 40 to 10 meters project by G8ODE published by RSARS

The page is about the 144 Mhz Dirty Beacon project, a VHF beacon keyer by 9A4QV. It provides technical information, project details, and resources for amateur radio operators interested in beacon keyers. The content is useful for those looking to build or learn about VHF beacon keyers.

Images of VHF UHF antennas

Drake Radio Repairs by Jeff WA8SAJ

The DL2NBY Contest Calendar, leveraging the Google Calendar system, presents approximately 400 **HF amateur radio contests**, detailing their dates and rules. It covers a broad spectrum of operating modes, including CW, SSB, and various digital modes like RTTY. The calendar integrates contest information from major organizations such as ARRL and DARC, providing a centralized repository for contest operators. This resource offers the capability to integrate contest events directly into a user's personal Google Calendar, streamlining contest planning. It functions as a comprehensive schedule, allowing operators to review upcoming events and prepare for participation across different bands and modes. The calendar's structure facilitates quick access to contest specifics, aiding in strategic contest operation.

The Yaesu FT-100 is a miniature mobile transceiver that provides coverage of the 160 to 6 meter bands plus the 144 MHz and 430 MHz bands

Topic regarding a new 1KW HF power amplifier with 2x GI7B

An interesting project about an Arduino-based frequency counter fot the Kenwood TS-520S