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This antenna is easy to build and suitable for broadband work, satellite work and terrestrial work. -
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Based on a design by JM1SZY for 50 MHz that he developed using YO -
Continuos coverage HF Transceiver by I6WJB & I6YPK -
There are many incorrect ideas and claims surrounding end-fed vertical antennas (like the I-Max 2000), end fed horizontal antennas, Zepp, and J-pole antennas. This article describes it. -
We worry a lot about Standing Wave Ratio (SWR) in amateur radio since SWR is one indication of how well our antenna system is working. Most HF transceivers and antenna tuners have built in SWR meters. SWR is a measure of a transceiver' s output power verses the portion of that power reflected by the antenna system -
A 144 MHz kilowatt amplifier project details the construction and performance of a high-power VHF linear using the GU74b tetrode. This Russian tube, equivalent to the Svetlana 4CX800, is noted for its conservative datasheet ratings, performing closer to 800-1000W anode dissipation in practical applications. The design prioritizes compactness and achieves 1.2 kW output with only 20W of drive power, demonstrating a 70% efficiency at 2.5 kV plate voltage. The amplifier has been successfully deployed in demanding _EME_ (Earth-Moon-Earth) operations since June 1994. Challenges encountered during development included achieving stability with a grid-1 input configuration. The author, _CT1DMK_, opted not to publish the full design due to its complexity, suggesting it might be difficult for less experienced builders to replicate successfully. However, he invites direct contact for those with specific interest in the design. Future plans include a "144MHz GS35b compact amplifier" project, promising another kilowatt-plus design. This resource offers insights into high-power VHF amplifier construction and the practical application of specific power tubes. -
This improved multiband trap dipole introduces a new trap design and a change in trap location. The antenna features double-coaxial-cable-wound traps having lower reactance and a higher quality factor (Q) than earlier coax-cable traps by W8NX -
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CW Skimmer 2.1 employs a high-sensitivity CW decoding algorithm based on Bayesian statistics, enabling simultaneous decoding of up to 700 CW signals within a receiver's passband on a 3-GHz P4 system when paired with a wideband receiver. The software features a fast waterfall display with sufficient resolution for visual Morse Code interpretation, automatically extracting and labeling callsigns on the waterfall traces. Extracted callsigns are exported as DX cluster spots via an integrated Telnet cluster server. The application includes a DSP processor with a noise blanker, AGC, and a variable-bandwidth CW filter, alongside an I/Q Recorder and player. It supports both 3 kHz radio passbands and wideband SDR receivers like SoftRock, RF Space SDR-IQ/SDR-14, SRL QuickSilver (QS1R), HPSDR Mercury, and Microtelecom Perseus. System requirements specify Windows XP/7/8/10 (32-bit or 64-bit), a Pentium-4 2.5 GHz for wideband operation or 1 GHz for 3-kHz radios, a COM port for CAT control, and a stereo sound card supporting 48 kHz sampling. It integrates with Elecraft KX3, Icom IC-7300/IC-7610, and Flex 6000 series radios, with documentation available for various setup configurations. -
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morse code machine to learn cw transmission -
The NCDXF/IARU International Beacon Project schedule provides precise transmission start times for 18 beacons operating on 14.100 MHz, 18.110 MHz, 21.150 MHz, 24.930 MHz, and 28.200 MHz. Each beacon transmits every three minutes, cycling through its callsign at 22 WPM followed by four one-second dashes. The initial callsign and first dash are sent at 100 watts, with subsequent dashes at 10 watts, 1 watt, and 100 milliwatts, enabling **propagation analysis** across varying signal strengths. The schedule lists the minute and second within each hour for the first transmission of each beacon on its respective frequencies. This resource allows **DXers** and **contesters** to accurately predict beacon transmissions for real-time propagation assessment. For example, 4U1UN transmits first at 00:00 on 14.100 MHz, followed by VE8AT at 00:10, and W6WX at 00:20, continuing the sequence. The page also notes recent hardware upgrades, such as the installation of IBP 2.0 controllers with Icom 7200 radios at some sites, and provides status updates for beacons experiencing hardware failures or those not recently heard, aiding in troubleshooting and managing expectations for monitoring. -
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Duplexers for dual band radio are usually high pass filter and low pass filter combined in the same box. This circuit is a design within a cost of US$10. -
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Strong RF HF power amplifiers made in europe ! Output 2,5KW 4KW PEP, 160m to 10m. -
A bazooka antenna project for the 7 Mhz, includes dimension for to homebrew your own bazooka for HF bands -
You'll find more than 330 Amateur Packet Radio Gateways on world maps. -
Attic Fan dipole antenna that allow to operate QRP from 40 metres to 10 metres, specifically 40, 20, 17, 15 & 10 meter band -
This resource provides a historical listing of **unlicensed amateur radio beacons** active in the United States as of December 1993, specifically detailing both **LOWFER** (Low Frequency Experimental Radio) and **MEDFER** (Medium Frequency Experimental Radio) operations. The data includes beacon frequencies in kilocycles (Kc), identification codes, state locations, and the callsigns or names of the beacon operators. Frequencies range from 166.667 Kc for LOWFER to 1706.0 Kc for MEDFER, illustrating the spectrum utilized by these experimental stations. The information was originally compiled by Mark Burkart and relayed to the rec.radio.shortwave newsgroup by Rick Robinson, KF4AR. The list serves as a snapshot of experimental beacon activity from the early 1990s, offering insight into the types of operations and the individuals involved in unlicensed, low-power transmissions. It highlights specific beacon IDs like "ABC SC" on 510.5 Kc and "GK HI" on 1620 Kc, alongside operator details such as Todd Roberts (WD4NGG) and Herb Vanderbeek (WY6G). While not a current operational guide, it is a valuable historical document for those interested in the evolution of LF/MF experimental radio and the early days of internet-based amateur radio information sharing. -
Antennas cover the RF spectrum from kilohertz to gigahertz and support countless mission critical military, air-sea navigation, ILS and voice-data communications applications. -
The N2CKH travel special 300 Ohm ladder line convertable antenna -
This project details three variants of a vertical half-wave antenna design for the 4-meter (70MHz) amateur radio band. The antennas use end-feeding with a parallel-tuned circuit for impedance matching to 50-ohm coaxial cable. The first variant uses suspended flexible wire for portable use, the second employs a fiberglass rod with internal wire for permanent outdoor installation, and the third utilizes aluminum tent poles for quick mobile deployment. Despite the narrow bandwidth of the matching circuit, this suits the narrow 4m FM allocation well. The design offers an effective omnidirectional radiation pattern and can be constructed with readily available materials. -
Radio control software for the Macintosh -
The article provides detailed instructions on how to build a half-sloper antenna for the 160 meters band. It explains the concept of a sloper antenna and how it differs from a slooper. The article includes practical tips on the construction and installation of the antenna to ensure optimal performance. The intended audience is amateur radio operators interested in building their own antenna for the 160 meters band. The content is informative, practical, and focused on DIY antenna building. -
TCUBE is a combination of a Spectrum Analyzer and a Two Tone Generator, with optional quadrature outputs. It can be used for measuring the intermodulation behavior of an audio circuit, and as a general purpose tool -
Some tens of very special audio files recorded during amateur radio activities like aurora traffic, meteor scatter, communications with ISS crew and the sound of various transmission modes that you can hear on HF and VHF bands -
The SoftRock-40 is a small, low-cost, good-performing "software defined radio" receiver that plugs into a computer USB port and delivers I-Q audio signals to the computer's sound card. It was designed by Tony Parks, KB9YIG and Bill Tracey, KD5TFD as an "SDR sampler project" for hams everywhere to easily try out software defined radio. -
This circuit is unique in that it uses a power mosfet as a final rather than a conventional bipolar transistor. -
This FET preamplifier has been around for almost 25 years. It is extremely reliable and can handle several watts directly into either the input or the output without failure. -
5 Elem. yagi for 10 meters, 9 element yagi beam antenna for six meters band by ON4ANT -
HF Vertical and Beam Antennas, antennas accessories by Butternut. Bencher is out ouf ham radio business. Recently company products has been sold to Vibroplex and DX Engenieering. -
The page provides a detailed guide on building a successful 160 Meter short TX loop antenna, with specific dimensions and tuning instructions. It includes information on the design, construction, and tuning of the antenna, as well as the materials required. The intended audience is amateur radio operators looking to build an effective antenna for the 160 Meter band. -
Mars Mod for Yaesu FT-450 extending frequency range: 1.8-30 MHz -
Listen to live scanner traffic from Santa Barbara, CA for Police, Fire, EMS, Sheriff, CHP. -
AirLink Express is a user friendly digital mode software package for the Amateur Radio Operator. The software is compatible with Microsoft Windows XP and Microsoft Windows Vista. It offers PSK, MFSK and RTTY digital modes with logging and macro capabilities. If you have ever used the Digipan software you will be immediately familiar with Airlink Express. The user interface is almost identical by Alex Krist, KR1ST -
Import-Export Worldwide shipment of Radio-scanners, shortwave-receivers and more. Wholesale and retail-trade -
FBB is a freeware bulletin board software for amateur packet-radio run on DOS Windows and Linux -
remote antenna switching project by EI7BA -
10 meters band aluminum 2-Element Moxon rectangle -
Two types of home-brewed 12/20 Ampere 13,8volt power supplies, including detailed part lists by ON6MU -
manufactures and distributes HF, VHF, UHF and SHF equipment covering 10MHz. - 47.0GHz. Our products include: Wireless LAN / WAN Bidirectional Linear Amplifiers, Low Noise Preamplifiers - LNA's, RF Linear Amplifiers, Relays, Transverter Systems, Frequency Translation Systems, Downconverters, Antennas, Parabolic Dishes, Coaxial Cable, Relays, Antenna Switches, Microwave Test equipment, PC controlled Receivers, Microwave Linear Amplifiers including models for Telemetry, Wireless, and CDMA applications. -
RXCLUS is a free windows amateur radio software especially designed for the DX'ers and SWL's wanting to receive the informations transmitted by packet radio on the DX-cluster system. It supports also telnet protocol. -
Demonstrates BBLogger, a **freeware** logging application designed for both amateur radio operators and Short Wave Listeners (SWLs). Developed by IK2VIW, IZ2BKT, and IK2UVR, this software provides comprehensive station management capabilities, including **CAT control** for various transceivers, integration with digital mode software like WSJT-X, JTDX, and MSHV, and robust QSL management features. The application supports a wide array of functions such as DX cluster interfacing, mapping, awards tracking (including custom awards), and direct integration with services like LoTW, eQSL.cc, and ClubLog for QSL confirmations and OQRS requests. It also includes utilities for ADIF to CSV conversion and vice-versa, catering to diverse logging and data management needs. Recent updates, such as version 13.1, introduce a web server for log management from any device, allowing remote access and control. The software has improved ADIF import capabilities, including time settings for duplicate QSO detection, and enhanced filtering options for log searches. Performance improvements include faster automatic updates and manager database synchronization, along with optimized log checking at startup. Earlier versions added support for FT8 and FT4 modes, refined OQRS integration with ClubLog, and expanded QSL/label printing functionalities, enabling users to select specific callsign types (OM, SWL) for printing. The developers emphasize compatibility with Windows 10/11 for full functionality, noting limitations when running on older operating systems like Windows 7 due to modern security protocol requirements. -
Ham Log book is written in MS Access. A good logging program that is very easy to use by Kevin Rea K6REA -
Manual for R7, 10 12 15 16 20 30 40 meters band antenna -
A home brewed rotary dipole antenna for 12 and 17 meters band with pictures and construction details -
A homebrew project of a quadruple helix antenna system based on G3RUH 16 turn helix antenna for 2.4 GHz. -
Schematics, mechanical drawings and picture of a Receiving loop antenna by N5ESE - N5FC