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A multiband vertical antenna for HF bands with elevated ground radials slant down at 45 degrees and acting also as guy wires.

An interesting article on how build an optimal sounding communications loudspeaker capable to optimize sound reproduction at the frequency range from 150 Hz to 3 kHz.

30 meters beacon from UK. QRSS is a method of sending very slow morse code.

Founded in 2000 by Jim Weidner, K2JXW, the ARLHS is the only society devoted exclusively to Maritime Communications and Ham Radio, Lighthouses and Lightships

Portable heavy-duty gas generators

Debco electronics, inc. - computers and electronic components for business, developers and hobbyists

The document explains the technical aspects of how the Internet Radio Linking Project (IRLP) works, focusing on the use of VoIP streaming software under the Linux operating system. It details the audio sampling, compression, transmission, reception, and playback processes involved in IRLP communication.

SkookumLogger is a free contest logging program for Mac OS X 10.7 or later, supporting CW and SSB events on the six HF contest bands plus 6m, 4m, 2m, and 70cm

This page only applies to TH D7A's that have a S/N below 010xxxxx and have not had their firmware upgraded by a Kenwood Service Center.

Fine tuning your Multiband Hustler Vertical

A study on 20m antennas by Kenny Silverman, K2KW

Digital multimeters, power supplies, frequency counters, RF analyzers, signal generators

The BTech DMR-6X2 dual-band DMR handheld radio is thoroughly reviewed, detailing its features and performance for amateur radio operators. This resource covers the radio's capabilities for both VHF and UHF frequencies, supporting Tier II DMR digital and FM analog modes. It highlights key specifications such as its **136-174 MHz** and **400-480 MHz** frequency ranges, CTCSS/DCS, DTMF, 2-TONE, and 5-TONE signaling, and its _digital simplex repeater_ function. The review provides a comprehensive unboxing experience, listing included accessories like two Li-Ion batteries (2100 and 3100 mAh), a programming cable, and a 37-page English user guide. It also specifies the radio's physical dimensions of 5.1 x 2.4 x 1.5 inches and weights of 9.9 oz with the 2100 mAh battery and 10.8 oz with the 3100 mAh battery, offering practical insights for hams considering this transceiver.

An open design exercise in interface archaeology, that decodes the input from a classic Morse key to send twitter messages

Operational mode QRPp QRSS Running as an MEPT Manned Experimental Propagation Transmitter

Long review of the Elecraft K3 , 18 months on.

Article on a QRSS receiver for 30 meters band

The C.A.R.E.N. Club is one of the oldest amateur radio clubs in Arkansas, dating back to the late 1950s. Just as the name implies, the C.A.R.E.N. Club is the state leader in emergency communications, SKYWARN, Amateur Radio Emergency Service (ARES), Radio Amateur Civil Emergency Service (RACES).

MiniDSP is a platform for digital audio signal processing applications. Manufacture low cost digital signal processor kits for the DIY/OEM market. Our flexible audio platforms are software controlled and easily upgradeable.

NewLogOSH is a logging application for amateur radio operators, featuring integrated support for various digital modes including FT4, FT8, RTTY, and PSK. The software incorporates DXCluster connectivity and radio interfacing capabilities, allowing for seamless operation with transceivers. Its database is built within the SQLite environment, providing a robust and portable data storage solution for logging QSOs and managing station information. The program's architecture focuses on practical functionality for daily amateur radio operations. Operators can utilize NewLogOSH for contest logging, general DXing, and managing their station's contact history. The inclusion of FT4 and FT8 modes reflects current trends in digital communication, while RTTY and PSK support caters to established digital protocols. The DXCluster integration provides real-time spot information, aiding in DX hunting and propagation analysis. Its SQLite backend ensures data integrity and ease of backup, making it a reliable tool for maintaining comprehensive station logs.

Review of the Retevis RT95 also marketed as Anytone AT-778UV dual band VHF UHF FM mobile radio transceiver

Manufacture high quality low cost powder cores with a wide selection of shapes

A review of the Superantennas MP-1 portable HF antenna

Constructing a compact directional antenna for the 17-meter band, this resource details the build process for a Moxon rectangle, a two-element Yagi variant with folded-back elements. It covers the antenna's evolution from the _VK2ABQ beam_ and provides specific dimensions for a version built using fishing pole whips. The content includes a discussion of the antenna's radiation pattern, feedpoint impedance, and its inherent front-to-back ratio, which is often superior to a standard two-element Yagi. Practical considerations for element spacing and material choices are also addressed, alongside a visual representation of the antenna's physical layout. Performance data presented includes a comparison showing the Moxon rectangle's **2.5 dB gain** over a half-wave dipole and a front-to-back ratio of **20 dB**. The resource also touches upon the antenna's relatively wide bandwidth for a two-element beam and its suitability for portable operations due to its compact footprint. It offers insights into optimizing the design for specific operating conditions and discusses the advantages of its lower take-off angle compared to omnidirectional wire antennas, making it effective for DX contacts on the 17-meter band.

This is an Arduino-based rotator interface that interfaces a computer to a rotator or rotator controller, emulating the Yaesu GS-232A/B and Easycom protocols which are supported by a myriad of logging, contest, and control programs.

The resource provides coaxial cable attenuation data, listing signal loss in dB per 100 feet for various cable types across a frequency range from 1 MHz to 5.8 GHz. The initial table details attenuation for cables such as _RG-58_, _RG-8X_, and RG-213, with impedance values of 50 ohm or 75 ohm, at frequencies up to 1 GHz. For example, _RG-58_ exhibits **0.4 dB** loss at 1 MHz and **21.5 dB** loss at 1 GHz per 100 feet. A subsequent table expands on this data, including LMR series cables like _LMR-400_ and LMR-600, along with other types such as 9913F7 and RG214. This section covers frequencies from 30 MHz to 1,500 MHz, also noting the outer diameter of each cable. For instance, _LMR-400_ (0.405" diameter) shows **0.7 dB** loss at 30 MHz and 5.1 dB loss at 1,500 MHz per 100 feet. The final section focuses on VHF/UHF/Microwave amateur and ISM bands, presenting attenuation in dB per 100 feet (and meters) for frequencies including 144 MHz, 450 MHz, and 2.4 GHz. This table includes larger diameter hardline options like 1/2" LDF and 7/8" LDF, in addition to flexible coaxial cables. For example, 1/2" LDF cable demonstrates **0.85 dB** loss at 144 MHz and 6.6 dB loss at 2.4 GHz per 100 feet. DXZone Focus: Coaxial cable attenuation | LMR-400 | RG-58 | 5.8 GHz

A shielded broadband (~200 MHz) active loop antenna offers more quiet and relatively less interference reception.

10MHz WSPR and QRSS Transmitter Project

Win32 command line utility, that allows you to create Master Callsign Database file (DTA), used in many contesting programs, from different logs in ADIF, Cabrillo, and plain text formats.

This PDF File include the serial commands to program and control the TH-G71. Should work with TH-D7 series too

The Orion II A9 Power Distribution Board Problem and Fix by N6IE

The dipole shown in this document is installed in an inverted Vee configuration, with two leg elements on each side held parallel to each other by 21cm spacers. The upper leg is for 40m and the lower leg for 20m. The spacers are made of 7mm plastic garden hose support for garden sprayers cut to 21cm.

Chip64 yahoo group, discuss about IZ8BLY chip 64 mode

How to make proper maintenance of your antenna. Fighting Antenna Corrosion is a QST article published in 1993 that helps on antenna maintenance works

Hams or amateur radio operators and CB operators usually cannot have ideal grounds, but with some care and planning they can have nearly perfect systems

This article deal with various means to covertly operate radio systems while going unobserved.

AO-51 Operating guidelines and introduction

Pictures, details and specifications about Yaesu VX-170

Electroswitch Electronic Products specializes in the design and manufacture of various switch types, including rotary, toggle, pushbutton, and rocker switches, as well as encoders and indicator lights. The company provides commercial and MIL-spec compliant components, detailing features such as spring return, push/pull to turn, adjustable stop, concentric shaft, and keylock configurations for their rotary switch lines. Specific product series like the M5-series enclosed frame rotary switches are highlighted, demonstrating their engineering capabilities. The resource offers a Rotary Switch Configurator to assist customers in selecting appropriate components based on application requirements. It categorizes switches by construction, such as enclosed frame, open frame, military grade, sealed, subminiature, blade, and power options for rotary switches. Toggle switches are presented in miniature, full-size, military grade, and sealed variants, while pushbutton switches include ultra-miniature, miniature, standard, and sealed types. Further product details cover rocker switches in subminiature, miniature, and sealed configurations, alongside thumb switches. Encoder offerings include magnetic and mechanical types with options like concentric shafts and push-to-turn functionality. Indicator lights are available for both commercial rectangular panel mount and MIL-spec applications, featuring configurations such as Press-to-Test, Watertight, EMI Shielded, and Dimmable options.

Linux for shortwave and amateur radio monitoring. Supports popular SDR hardware and online streaming from KiwiSDR, WebSDR, and Spyserver sites. Articles about using Linux with your SDR devices.Skywave Linux, an innovative operating system, leverages cutting-edge technology for seamless access to radio signals globally. Ideal for regions with limited internet access, it effortlessly connects to a network of SDR servers, offering high-performance SDR operation without the need for extensive hardware. With pre-installed and configured SDR software, Skywave Linux simplifies signal discovery and operation for all users.

Resources for custom battery chargers and power supplies from powerstream

Pileup simulator for for the existing and future DX-pedition operators, and for those who are curious how it feels to manage a pileup.

RoMac Automatic CW Identifier 2012 and Tuning Pulser for windows, sends your callsign at programmed intervals, to ensure your stations compliance with FCC regulations. No more forgetting to ID. Commercial version, demo available.

The mid florida dx association was formed in february 2005. to promote friendship and cooperation among amateur radio (wireless) operators primarily

How do two-wire reversible direction Beverages work, an excellent document that explains fundamentals of beverage antennas. This article details the design and performance of a reversible beverage antenna. Leveraging orthogonality between common mode and differential mode currents on a 2-wire line, this antenna facilitates independent reception from both ends. While common mode signals arrive and are summed on a transformer's secondary for common mode reception, differential mode signals induce anti-phase currents, providing individual reception. Various measurements explore impedance, transmission loss, and F/B ratio, highlighting the antenna's effectiveness and areas for improvement. Notably, increasing the antenna's height significantly improved performance.

Hard to find Kenwood Parts available for shipping worldwide

QSL Printer shop, products include Photo QSL cards, Eyeball cards, and State QSL Cards, based in Hampstead, MD USA

Commsaudit uk, i/q quadrature , hf receivers, rf, multicoupler, multicouplers, switch matrix, antenna matrices, masthead amplifier,, vhf receiver, uhf,

LEMO, established in 1946, specializes in high-performance interconnect solutions, offering an extensive range of over 50,000 circular connectors. Their product line includes the REDEL SP IP68 series, which features resin-free IP68 sealing for robust performance without complex potting processes. These connectors are critical for applications in medical, military, test and measurement, security, defense, and industrial sectors, ensuring reliable signal integrity in harsh conditions. The company designs, tests, and manufactures high-quality cable solutions, providing complete connectivity services such as custom cable assembly and signal integrity analysis. LEMO's solutions are integral to advanced scientific endeavors, as demonstrated by their use in CERN’s NA62 experiment for instrumentation and maintenance. LEMO's 80-year history, detailed in their anniversary publication, highlights their evolution from a Swiss family workshop to a global leader in connector technology. Their product finder tool assists customers in selecting appropriate connectors from their broad portfolio, which also serves audio-video, transportation, aerospace, and UAV applications.

An early review of the Icom IC-7300 HF + 6M Transceiver includes four videos demonstrating reception on 40 meters band