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Shortwave listeners and amateur radio operators interested in _numbers stations_ can engage with this mailing list, which serves as a platform for discussing the enigmatic transmissions. The resource facilitates the exchange of information regarding these unusual broadcasts, often associated with intelligence agencies, by allowing members to share observations, decode attempts, and theories. It provides a community space for those who monitor the HF spectrum for these unique, often automated, voice or digital signals. Participation on the list enables members to contribute to a collective understanding of numbers station activity, including changes in frequencies, broadcast schedules, and message formats. While specific technical analysis or signal processing techniques are discussed by members, the primary function is information sharing. The list is administered by csmolinski at blackcatsystems.com, and prior postings are archived for reference, allowing new members to review historical discussions and data.

VHF UHF SHF Toplist including DXCC and EME-Initials

Yagi with 5 Elements on 2 m, 8 Elements on 70cm and one Feedpoint by DK7ZB

The North East Weak Signal Group (N.E.W.S.) website serves as the digital hub for an ARRL-affiliated regional club dedicated to _weak signal_ work across the VHF, UHF, and SHF spectrum, from 50 MHz up to light. It provides essential information for members and prospective enthusiasts, including the club's constitution and by-laws, details on officers and the board of directors, and a calendar of meetings and events. The site also features an application for membership, information on dues, and a membership roster, fostering a sense of community among its over 100 members. A significant feature of the site is its extensive archive of conference papers, including proceedings from the _Eastern VHF/UHF/Microwave Conference_ dating back to 2009. These papers cover a wide array of technical topics relevant to weak signal operations. The site also lists _50 MHz Beacons_ and _144 MHz and up Beacons_, along with links to other VHF and above resources, providing practical tools and knowledge for operators interested in pushing the boundaries of amateur radio communication.

This resource, originally intended to detail the technical specifications of the **Clover** digital communications mode, currently presents a "Page not found" error. The _Clover_ mode was designed for conveying 8-bit digital data over narrow-band high-frequency radio channels, offering robust performance under challenging propagation conditions. Its design focused on efficient data transfer and error correction, making it suitable for amateur radio operators seeking reliable digital links. The absence of the page prevents analysis of specific technical parameters, such as modulation schemes, data rates, or error correction codes that would have been presented. Historically, Clover offered significant advantages in throughput and reliability compared to earlier digital modes over HF, often achieving higher effective data rates than modes like PACTOR or AMTOR under similar signal-to-noise ratios. Without the content, a direct comparison of its performance metrics or practical application scenarios is not possible.

TS-570 series specifications at universalradio

My Top Five Backyard Multi-Band Wire HF Antennas. A selection of the top 5 HF wire antennas for the backyard and for multi-band operation

The DK5YA Vhfdx Site is dedicated to the serious VHFDXer, serving the Web for more than 5 years for all of those working Aurora, Meteorscatter, FAI, EME, Tropo, TEP etc. on 50 MHZ and up.

70 MHz transverter, 4m band, by G3XBM

Kenwood TS-590S features, accessories, specifications and details

Design of a 40 meter Vertical antenna

US coast guard frequency list

The following table is adapted from the International Telecommunications Union Radio Regulations Appendix 18, including changes adopted by the 2012 World Radio Conference.

Get familiar with the basic operating procedures for using the JT65 mode of HF digital communications, a 35 pages PDF file.

Linear Amp UK specializes in the design and production of high-quality linear amplifiers, offering models for HF, VHF, and UHF amateur and commercial applications. The company emphasizes nearly 30 years of experience in crafting each unit, ensuring robust performance and longevity. Their product line includes amplifiers engineered for a 100% duty cycle, promoting continuous and reliable operation across various modes. The amplifiers feature solid, dependable designs, ensuring quiet and effortless performance during transmission. Each unit is hand-built to stringent standards, reflecting a commitment to durability and operational stability. All products are CE approved, confirming compliance with European safety and environmental directives, and come with a standard two-year warranty, providing assurance to operators. Key specifications often include coverage for 1.8-30MHz (WARC bands), 50MHz, 70MHz, and 144MHz, utilizing tubes such as 811, 572, 811A, 572B, GS35, GS35B, 8877, 3CX1500, and _3CX1500A7_ in their designs.

Find out how much to adjust the length of a quarter wave whip or a half wave dipole rather than the outright cut-and-try method.

Cushcraft A3S HF antenna 1:1 balun repair.

What makes a good solid-state amp ? by Adam Farson, VA7OJ/AB4OJ, May 2002

This circuit enables fair copy of strong 444 MHz signals, off a local repeater, using a 2m rig and a 1/4λ 70 cm indoor ground plane antenna.

Compiles a detailed calendar of RTTY contests, providing essential information for digital mode enthusiasts. It lists contest dates, links to official rules, and often includes historical results and records, enabling operators to plan their contesting schedule and review past performances. The resource covers a wide array of RTTY events, from major international contests like the _ARRL RTTY Roundup_ and _CQ WW RTTY_ to smaller, regional competitions. Operators can quickly identify upcoming RTTY contests, review specific rules for each event, and access historical data to gauge competition levels. For example, the site details the _BARTG RTTY Sprint_ and the _SARTG New Years_ contest, offering a centralized hub for RTTY contesting information. This resource is particularly useful for those aiming to improve their digital contesting skills or track their progress against established **records**.

The resource details the construction of a multiband trap-style Inverted-V antenna designed for operation on 3.5 MHz, 7 MHz, 14 MHz, 21 MHz, and 28 MHz. It presents specific winding data for the traps, including the number of turns, wire gauge, and coil former dimensions, crucial for achieving resonance on the target bands. The document provides a parts list and a diagram illustrating the antenna's physical layout and trap placement. It outlines the process for building the traps using PVC pipe formers and specifies the required capacitor values for each trap. The design emphasizes a practical approach to achieving multiband operation with a single feedline, a common goal for HF operators with limited space. The document includes a table with antenna segment lengths for each band, allowing for precise replication of the design. It also offers insights into tuning and adjustment, ensuring the antenna performs optimally across the designated amateur radio bands.

Meteor scatter, gives quick view over meteor scatter and scatter events on vhf, lists email addresses of vhf radio amateurs qrv in meteor scatter

Shelby amateur radio club's VHF emergency net is open to all within the repeater's coverage area. 146.880 and 147.345 are the repeater frequencies. Shelby Radio Club is the sponsor of the Shelby hamfest.

A new, simple way to build the Eggbeater Antenna. This document introduces a new, simpler way to build the Eggbeater antenna. It also introduces a technically proper way to construct the Eggbeater antenna in order to achieve the best result.

MP3 and Wav files of some stations recorded on HF anc VHF bands by K9MU

Using a PC with soundcard as a VLF receiver, how to use your PC as a receiver for narrow-band signals in the VLF radio spectrum by DL4YHF

Hi-Z Antennas offers specialized high-impedance receiving systems, primarily focusing on phased vertical arrays for HF reception. Their product line includes preamplifiers designed for shortened vertical antennas, featuring optimized 15dB gain and array-matched characteristics. These components are engineered to enhance weak signal reception and improve signal-to-noise ratio across the HF spectrum. The company provides controllers for managing multiple vertical elements in a phased array configuration, enabling directional reception patterns. These systems are particularly effective for mitigating local noise and interference, a common challenge in urban and suburban operating environments. Specific offerings include solutions for 160-meter and 80-meter bands, addressing the unique requirements of low-band DXing. Technical details often reference components like the 2N3866 transistor in preamp designs and discuss concepts such as out-of-band attenuation. The focus remains on optimizing receiving antenna performance through impedance matching and active amplification, rather than transmit capabilities.

A magnetic loop antenna for the VHF band, featuring a high gain that can be compared to a quarter wave vertical antenna

The fan dipole antenna as an alternative to the paralled dipole antenna, to achieve a larger bandwidth and a better tuning by decreasing elenment influences.A project based on the W6HDG original concept.

This circuit came out of some work done for two antenna analysers

A ten element ultra-lightweight yagi beam antenna for 144 MHz based on YU7EF design concept

Hams have been putting stations in their cars since the Twenties. Today, there is great satisfaction in facing the challenge of installing a transceiver in our small cars and pick-ups, using somewhat inefficient antennas

Description and simulation of two types of rhombic antennas, using the software 4Nec2: the simple bi-directional and the terminated directional rhombic antenna

A home made project for a 3 to 12 MHz signal generator

Concentrating on VHF DX, Aurora, Meteorscatter, TEP, Sporadic E, EME, VHF DXpeditions. Daily updates.

An home made HF mobile multiband antenna inspired by the KM4IE HF 20 dollars antenna or the Texas Bugcatcher can work 75 to 15 meters band with an acceptable SWR.

Here are 10 tips and truisms that every ham should know about antennas, by W20QI

Irish ham and Vhf radio info. Logs and maps worked, no excuses, this is mainly a VHF site

As used on the new GB3VHF 144.43MHz Beacon

Quarter wave groundplane antenna for 2 meters FM by AA1PG

The Ameritron ALS-600 600-Watt HF Power Amplifier review by AD5X

This article describes the design and simulation of a multiple dipole antenna for the HF band, using the software MMANA-GAL. The antenna will be designed to operate in the 10, 20, 40 and 80 m bands

Pictures and project design of a crossband VHF UHF repeater by LY3H

An Antenna Mast Idea for a VHF/UHF antenna

Technical specification by Universal Radio

A handy piece of test equipment useful for HF bands, can absorb a 200W modulated carrier for almost 2 minutes. It is housed in a tin and part filled with dry sand that helps in power dissipation

Presents the construction of a 2-meter **Skeleton Slot Yagi** stack, detailing the design process and practical considerations for VHF operation. The author shares insights from building and testing this antenna, emphasizing its performance characteristics for local and extended range contacts. The project outlines the specific dimensions and materials used, providing a clear path for other radio amateurs to replicate or adapt the design for their own stations. The resource covers the unique aspects of the Skeleton Slot radiator, explaining how its geometry contributes to gain and pattern control. It includes discussions on impedance matching and feedline considerations crucial for optimizing power transfer and minimizing SWR. The article draws on real-world testing, offering practical results that validate the theoretical design. This project serves as a valuable reference for those interested in custom VHF antenna solutions.

Assembling the Butternut HF9v HF vertical antenna

HFRadio.US is a woman-owned small business that specializes in products for the HF market. We have our own line of broadband HF antennas plus other specialized products primarily for the Motorola Micom series radios.

Acom 1000 operating manual in english