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This version of the broadband hexbeam is based on the work of Hunt G3TXQ, HB9MCZ, and Shoemaker K4KIO. EZNEC model is based on a wider element spacing than the version published in QST by K4KIO

Charlie Papa India RhAne-Alpes & Bourgogne HQ

A manufacturer of standby and prime power generator sets for industrial, telecommunication, commercial, small business, mobile and residential applications.

Amateur radio repeater scanner at Pomona California

Spectrum Microwave is a market leader in the world of RF & Microwave components and system

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.

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

Ararat Shrine Radio Club of Kansas City

Javascript filter design page with introduction to low pass filters by k7mem

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

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

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.

Full color QSL printer in Poland

Kenwood TS-590S QST review comments and table comparison vs Elecraft K3

Fine tuning your Multiband Hustler Vertical

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.

Portable heavy-duty gas generators

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

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.

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.

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

Long review of the Elecraft K3 , 18 months on.

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

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

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

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.

Hard to find Kenwood Parts available for shipping worldwide

Resources for custom battery chargers and power supplies from powerstream

Article on a QRSS receiver for 30 meters band

A study on 20m antennas by Kenny Silverman, K2KW

The Superantennas MP-1 portable HF antenna is analyzed for its design and field performance, particularly its high-Q loading coil and 3/8-inch mounting. The review details the antenna's construction, including an 8-inch vertical section, a large-diameter loading coil tuned by a sleeve, and a 4-foot whip that disassembles into six rods for transport. Initial testing with the supplied 10-foot ribbon cable "ground plane" yielded poor SWR and RF hot conditions, indicating an inadequate ground system. Further experimentation with longer radials and resonant counterpoises for each band improved matching and eliminated RF hot issues, but introduced significant operational complexity. The author notes the difficulty in optimizing both counterpoise length and coil setting without an antenna analyzer, and the sensitivity of the MP-1 to counterpoise deployment. The review also discusses the recommendation to tune for maximum received signals rather than minimum SWR, often necessitating an external ATU due to the antenna's typical low impedance. The **MP-1**'s critical dependence on resonant counterpoises for effective operation, especially when elevated, is highlighted as a major drawback for portable use. The author ultimately sold the antenna, concluding that despite its sound technical design, its fussy nature and the need for extensive counterpoise management or an ATU detract from its portability and convenience compared to simpler, less expensive dipole solutions. The **Superantennas MP-1** is deemed a flawed portable antenna, requiring considerable effort to achieve its claimed performance.

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).

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

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

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

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.

This article reports and collect some frequencies used during 2020 Ukraine war and reported as being used by army forces. HF communications are still a crucial part of military communications and can ben monitored on web sdr radios available on the internet.

Chip64 yahoo group, discuss about IZ8BLY chip 64 mode

L4B by Drake amplifier mod

Demonstrates the _RoMac Automatic CW Identifier 2012_ software, a Windows application designed to automate station identification and provide a tuning pulser. It can send CW identification via a sound card's audio output or by keying a radio's manual CW jack using a serial port's DTR line. The software also supports CAT commands for various Kenwood, Yaesu, Flex, and Elecraft radios, enabling automatic mode and frequency changes for ID transmission. It integrates with USB audio-capable radios like the Icom 7300 and Yaesu FT-991, simplifying connectivity with a single USB cable. The application features a fully programmable interface, adjustable CW speed from **5 to 35 WPM**, and ID intervals from **5 to 30 minutes**. The integrated "Pulse Tuner" function allows for safe amplifier and antenna tuner adjustments by sending short audio tones or rapid CW keying, with an adjustable duty cycle from 1% to 100%. It offers compatibility with a wide range of transceivers and amplifiers, and a schematic for a basic sound card interface is included for users without existing setups.

AO-51 Operating guidelines and introduction

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

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

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.

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

A borderline insane 30m QRSS beacon project, completely independent of computer control and containing NO microprocessors!