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This review of progress and future Prospects provides a practical guide for effective use of VHF sporadic-E propagation.

DXSPOTS is a Telnet connection program. It allows radio amateurs with a lot of DX traffic to know instantly the status of the bands and to know which DX are currently on the air. Following the Packet-Clusters where data was transmitted on VHF/UHF via dedicated relays and sometimes on HF at a very low speed (300Bds on HF), the Internet has taken over and is now transmitting DX information via the computers in most shacks. Translated with www.DeepL.com/Translator (free version)

RDF Equipment Ideas for VHF Foxhunting and Radio-Orienteering. This information is primarily for the Amateur Radio two-meter band

eHam reviews of the Mirage BD-35 VHF UHF Amplifier

DMR Handheld TDMA Tier I and Tier II VHF or UHF product review with information on accessories

Duoband Yagi 2m/70cm with 4 Elements on 2 m and 5 Elements on 70 cm and one Feed point. The 4-El.-Ultralight-Yagi for 2m can be used on 70cm with an SWR of 1,5 without any changes.

An article on amplitude modulation (AM) operation on VHF bands.

Creating a 2m Fm Repeater with a Raspberry Pi (B) and a RTL dongle.

Review of Yaesu VX-3R 2 m/70 cm FM transceiver. Receives 0.5-999Mhz AM/FMN/FMW, Transmits 144-148 and 430-450Mhz VHF/UHF FM.

HF digital mode transmissions, voice transmissions in HF and VHF Bands collected in several XLS files by Relic Radio communications

Promote and coordinate the installation and use of VHF/UHF amateur repeaters throughout Utah.

Responsible for the operation of amateur radio repeaters GB3FM, GB3FN and GB3FX which are located near Farnham, Surrey in Southern England

A concept to use common, low-cost parts to mount a VHF/UHF dual-band antenna to help people who have HOA restrictions, are renters, or desire low-visibility characteristics get on the air.

2m 70cm 23cm Low noise Amplifiers, 3 Low noise amplifiers Outdoor unit with DB6NT parts completed.

Tucnak is multiplatform VHF/HF contest logbook. It is executable on Linux and other unix-type systems. Since v3 also native under MS Windows, Android and Kindle

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.

Icom ID-880 VHF/UHF dual band transceiver reviews on eham.net

Home of Club Station V31HQ, The Maya Hill Lodge, is ideal DXing from Central America. The shack is located outside the house as separate house and it is air conditioned. Offer HF VHF UHF equipment and EME setup.

A nice QRP, EME, satellites, VHF DX, Amateur radio blog by Lars Petersen OZ1BXM

Description of an optimal backpack used for pedetrian mobile operation both on HF and VHF bands.

The J-Pole antenna is a common omnidirectional antenna used in amateur radio, particularly on the VHF and UHF bands. This article is an attempt to explore how the J-pole antenna transforms feed-line impedance to free-space impedance, all the while providing gain found only in the more expensive commercial products.

The Bazooka antenna, a coaxial dipole, functions as an omnidirectional antenna with vertical or horizontal polarization. Patented in 1939 and refined in 2006, it features a quarter-wavelength coaxial cable with separated conductors. The outer conductor connects to a sleeve, while the inner conductor extends vertically. Initially complex, it has been simplified for versatile use, including military applications. Adding elements can modify its behavior for NVIS or Yagi-Uda configurations. Experiments in 2007 at the Campus de Pesquisas Geofísicas in Paula Freitas-PR demonstrated consistent VHF and UHF performance, showing reliable return loss measurements despite variable weather.

DXLook is a free, web-based propagation platform that delivers comprehensive, real-time insight into HF and VHF conditions directly from any modern browser. It aggregates live spots from PSK Reporter, WSPRnet, RBN, and DX Cluster, complemented by NOAA space-weather metrics such as SFI, K/A indices, and geomagnetic alerts. Integrated VOACAP predictions allow practical "theory versus reality" comparisons, while the interactive world map with filters, gray line, and grid overlays enhances situational awareness. With no installation or maintenance required, DXLook provides a convenient, accurate, and accessible solution for everyday operating and propagation analysis.

Since 2012, the RTL-SDR is the simple and cheap way to give Software-Defined Radio a try. For about 25 euro you get a receiver covering much of the VHF and UHF range, and by either adding an upconverter, or using the direct sampling option, also the HF bands. They are so cheap because they are mass-produced as DVB-T receivers.

Ribbit is a novel digital text messaging mode for VHF/UHF communications for recreational and emergency use which radically increases the density of information transmitted by spectrum used. It leverages the computing power of the modern smartphone to increase the capabilities of any Handy Talkie without requiring any additional hardware or cable. A Ribbit message is fixed in duration at 1250 milliseconds. It is sent over audio modulation with a 2kHz bandwidth centered on 1.5kHz. It is preceded by 400ms of white noise to open analog squelch circuits.

Amateur radio antenna manufacturer, HF VHF UHF antennas, and amateur radio accessories dealer based in Lingen Germany

Artic is a program dedicated to amateur radio contest log checkers, mainly in Italian offers log checking function for VHF contests like IAC in Italy and SWAC in Switzerland

This project introduces the SN 1/8 mobile antenna, a compact and mechanically stable alternative to traditional 1/41/4 or 5/85/8 wave antennas. Designed for VHF/UHF mobile communications, this 20 cm antenna offers superior performance in moving environments. Its spherical radiation pattern enhances reflections, providing a 2 dB gain. Ideal for vehicle use, it is discreet, easy to install, and resistant to vibrations, making it a practical choice for mobile users seeking reliable and efficient communication. In French.

Invicta Contest Group, Based in Kent, england, Mainly large VHF Contests.

Low Cost Satellite Antennas article was originally presented at a Project OSCAR seminar on September 30th, 1990. AMSAT-UK printed an abridged version of this presentation in their OSCAR News, Number 88, April 1991. The original presentation has been reedited and updated for AMSAT's Web page.

A 70cm / 432 MHz Transverter Project transverter circuit is an electronic device that converts a radio signal from the 2 meter to the 70 centimeter band and vice versa, allowing a single transmitter/receiver to be used for both bands. It consists of an IF stage, local oscillator, frequency multiplier, and amplifier. The circuit must be designed for minimal signal loss, noise and intermodulation distortion.

This article describes the construction of a simple dual-band VHF/UHF end-fed vertical dipole antenna designed for local repeater access using an Icom IC-705 radio. Built from a single piece of RG58U coaxial cable, the antenna consists of a 460mm exposed inner conductor, 450mm of intact coax, and a 9-turn choke balun wound on a 27mm former. Mounted on a 10m Spiderpole, the antenna achieves excellent SWR readings (<1.2:1 on 2m, <1.5:1 on 70cm) and provides effective coverage of local repeaters with unexpected reach into distant locations.

Thunderstorm effects on sporadic E propagation, Very long distance propagation in the 144 MHz band, Analysing the number of skips in multiple hop propagation

IAT is an excel sheet table evaluate parameters of VHF UHF antennas edited by Vladimir UR5EAZ. The difference between this tool and the existing VE7BQH Antenna Table is the use of G / T and C / N instead of the G / Ta parameter. In this table, Vladimir applies the ITU recommendations to assess the noise properties of a radio receiving system and shows the advantage of the G / T concept over the G / Ta concept when choosing an antenna.

The TYT MD-2017 dual band VHF & UHF DMR portable radio review

The HB9CV antenna calculator aids amateur radio enthusiasts in designing antennas for VHF and UHF bands. By inputting the working frequency, users can obtain crucial dimensions like dipole lengths and distances. The tool, based on the HFSS antenna model, provides data on impedance, VSWR, and gain, optimizing front/back radiation ratios. It includes tips for fine-tuning using a Г-matching balun and compensating capacitor, ensuring effective performance and minimal VSWR for enhanced radio communications and direction finding.

KM Rover is a rover logger software for BIG 4 VHF UHF contests and generic, Spring and Fall Sprints, GPS interface, beam heading CW PTT DVK functions. Works on Windows

Amateur radio antenna manufacturer produces mainly VHF UHF beam antennas based in Germany

Discover the success story of creating a 4-meter Delta Loop antenna, ideal for improving radio communication. This horizontally polarized antenna offers efficient performance when mounted at VHF heights, catering to both HF and VHF characteristics. A simple, DIY project suitable for portable setups, providing versatile options for radio enthusiasts.

144 Mhz EME Basics, Weak Signal VHF by Tim Marek that will help you make informed decisions as how best to be proceed in constructing a EME station of your own.

The Maine 2 meter FM Simplex Challenge is a ham radio contest primarily designed to give 2 meter operators a chance to compete on an even basis, and have fun doing it.

A 5/8 λ antenna, often thought to be ideal for all frequencies, has unique characteristics that don't universally apply. First introduced for medium-wave radio, it works optimally at 225° antenna length over ideal ground, yielding high efficiency. However, at VHF and higher frequencies, it offers no advantage over other antennas due to real ground conditions and complex matching requirements. DIY calculators provide only rough estimates, useful as a starting point for simulations, not for precise builds.

Learn how to easily improve your handheld VHF performance on the 2-meter band with the Flowerpot antenna. This simple DIY antenna made from coaxial cable requires minimal tools and materials, providing a big range upgrade compared to standard rubber-duck antennas. Discover how to build, tune, and optimize the Flowerpot antenna for excellent performance. Ideal for hams looking for lightweight, portable solutions for handhelds, mobile rigs, home stations, SOTA/POTA activations, and emergency communication.

This DIY guide details constructing a 5-element Yagi antenna for VHF frequencies. Yagi antennas offer directional signal transmission/reception compared to omnidirectional ones. The guide covers material selection (aluminum, screws, etc.), design using software or formulas, and step-by-step assembly including cutting elements, drilling holes, and attaching the coaxial cable. While calculations are provided for a 146 MHz design, adjustments are necessary for different frequencies. Safety precautions and potential result variations are emphasized.

The most basic form of repeater receives communication on one frequency and re-transmits at a different frequency. This is known as duplex communication. Repeaters are generally set up to operate with FM modulation on the amateur bands within the VHF (30 MHZ – 300 MHZ) and UHF frequencies (300 MHZ – 3 GHz). These are generally the frequencies used by handheld and mobile devices.

Reviews for Elecraft K4 HF Amateur HF 6M VHF UHF at eham.net

We are a group of amateur radio operators located in Northern Utah who enjoy exploring many aspects of the hobby from HF to VHF and beyond. We are active in many public service events, Field Day, APRS, packet, Winlink, contesting and more

This project introduces the Loggi, a hybrid antenna merging the wide frequency coverage of log-periodic dipole arrays (LPDA) with the high gain and front-to-back ratio (F/B) of Yagi antennas. Traditional LPDAs span broad frequencies with moderate gain and low VSWR, while Yagis provide high gain and F/B over narrow bands. By analyzing high-Tau LPDA designs, it was found they could nearly match the gain of VHF/UHF Yagis while maintaining excellent patterns, F/B, and front-to-rear ratios (F/R). Optimizing specific elements for target frequencies (e.g., 144.1 MHz) led to the Loggi, which uniquely features all driven elements without passive directors or reflectors. This design effectively functions as a narrowband optimized LPDA, with front elements acting like Yagi directors and rear elements like Yagi reflectors, thus enhancing gain and directional characteristics while retaining broad frequency versatility.

Stop EMI RFI Interference in Off Grid Solar PV Systems, in this article the author provides hints on tracking down the EMI or RFI source, shielding and grounding in order to eliminate interferences on the whole HF and VHF ham radio bands

The 8m ISM band, a unique frequency range between 10m and 6m, holds potential for amateur radio enthusiasts, yet it remains largely unallocated. This spectrum offers fertile ground for research and self-training. The author's experience with low-power transmissions and WSPR testing highlights the band's capabilities and the need for a narrow, speech-free amateur allocation to encourage experimentation. Discover the world of 8m ISM radio exploration and its future possibilities.