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This Multiband Cubical Quad antenna a boomless Quad design with glass-fibre arms and a single coax wire connected to a remote antenna switch. This aerial work on 8 bands and has a 60-degree beam width. Despite achieving critical technical requirements, the antenna's three-dimensional structure presents obstacles, such as installation issues on fixed towers and risk of frost damage. The spider framework is built of stainless steel, with a compact 18-inch boom and strong angle iron arms. Tait use a variety of methods to fasten element wires and suggests placing them on the outside of the spreaders for improved insulation. The use of nylon twine or parachute cord between key attachment points allows for adjustable separation between pieces.

Dipole, Yagi, Vertical, Cubic quad, Log periodic, J-pole, coil, and transmission line design package for the Macintosh

Interesting article on mobile antennas by Cebik. . The article offers advice for setting up and operating mobile antennas for ham radio use. It emphasizes the lossy nature of mobile-in-motion antennas but encourages users to rise to the challenge. Steps include safeguarding car electronics, choosing proper cabling, and carefully selecting and mounting antennas. It highlights potential issues like roof mounting, trunk lip grounding, and side-mounting for trucks. For stationary operation, options like dipoles or beams are explored, with safety tips for masts and guying systems. Lastly, it stresses safety, suggesting stopping the vehicle to operate whenever possible

Review of the W5GI Multiband Mystery Antenna by July 2003 Issue of CQ Amateur Radio

A half sloper antenna for 160 meter band Italian translation of a WD8DSB article appeared in a QST issue during 1998. This article presents a **Reduced-Size Half Sloper Antenna for 160 Meters**, designed for amateur radio operators with limited space. By utilizing a 40-foot tower or a tree, you can build an efficient antenna that slopes down, achieving a 2:1 SWR bandwidth of 120 kHz. This innovative design allows for effective communication on the "Top Band," making it ideal for winter DXing.

Amateur radio Services by the Federal Communications Commission.

Demonstrates an online **CW** audio decoder tool, currently under active development, designed for analyzing and decoding Morse code. Users can upload audio files containing Morse code or record live audio input via a microphone, with processing handled entirely in JavaScript using the Web Audio API. The software analyzes the audio, attempting to determine the pitch and speed, and then decodes the message, providing options to compare the decoded output against a predefined message or a perfectly timed version. The interface allows for setting optional comparison messages, character speed in WPM, and Farnsworth speed. It also features interactive charts for visualizing the audio analysis, where users can zoom with the mouse wheel and pan by dragging. Specific buttons highlight different element types such as intra-character space, inter-character space, extra elements, missing elements, and replaced elements, aiding in detailed signal analysis. Built-in test files are available for immediate analysis, allowing users to quickly evaluate the decoder's performance. The tool is noted to work with specific browsers and is presented as a testing platform for user feedback, indicating ongoing refinement of its decoding algorithms and user interface.

This project shows how to build a 50-ohm dummy load using non-inductive resistors, oil for heat dissipation, and a simple assembly process. It enables accurate transmitter tuning, testing, and power measurement across LF to UHF bands. The setup allows meter calibration by measuring peak voltage, applying diode drop correction, and calculating RMS voltage and power precisely. Parts are inexpensive and widely available. With proper assembly, this dummy load offers extended service life, accurate readings within 2%, and a reliable alternative to costly commercial wattmeters for amateur radio applications.

Over 40 years of experience inform the reviews and commentary presented on Dave's Radio Receiver Page, covering a wide array of radio receivers and transceivers. The resource details specific models such as the **ICOM IC-R8600** SDR Communications Receiver, which is lauded as Icom's best wide-band receiver, even surpassing the IC-R9500 in performance. Other notable reviews include the ICOM IC-7300 HF Transceiver, highlighting its direct sampling SDR technology and spectrum scope capabilities, alongside numerous models from Japan Radio Co. (JRC), Kenwood, Yaesu, and various portable shortwave receivers. The content provides practical insights into the performance and characteristics of each radio, often drawing comparisons between models. For instance, the early issues with the AOR AR7030 receiver's Bourns mechanical encoders are thoroughly documented, including AOR's eventual switch to higher-quality Alps encoders. The page also features reviews of antennas like the MFJ-1026 Noise Canceling Signal Enhancer and various power supplies, offering a holistic view of radio monitoring setups. The author's "2 ear / 2 eye method" emphasizes real-world listening experiences over laboratory measurements, providing a unique perspective on equipment utility.

Version 1.4.6 of _AAVoice_ functions as a digital voice processor for amateur radio, designed to operate on Windows platforms from 9x through 10. This software leverages pre-recorded WAV files for transmission, allowing operators to send pre-defined messages or calls efficiently. Its core functionality includes PTT control, which can be managed through a simple circuit connected to a COM port, providing a reliable interface for radio keying. The program offers extensive macro capabilities, streamlining repetitive transmissions during contesting or DXing. It also features direct integration with the _AALog_ logger, enhancing workflow for those using DXsoft's suite of tools, and can interface with other compatible programs via its COM-interface. Author Alexander Anipkin designed _AAVoice_ to require a working sound card, and it comes with a basic set of sound files. Users can easily create additional WAV files using standard Windows sound recording utilities, ensuring flexibility in customizing audio content for various operating scenarios.

Real 4:1 Transmission Line Balun with Balanced Load

Simple eprom programmer for 27Cxx family , used in TNC and G3ruh modem, eprom tutorial, schematics and KissEprom software for windows by iz7ath

The "EZ-Tuner" is a homebrew automatic legal-limit antenna tuner that covers all amateur HF bands from 160-10 meters. Using a T-network design and controlled by a BASIC Stamp BS2sx microcontroller, the EZ-Tuner will match at least a 16:1 VSWR for either unbalanced or balanced transmission lines.

Argo, developed by I2PHD and IK2CZL, functions as a specialized freeware viewer for various weak signal modes, specifically MTHELL, Slow CW, QRSS, and DFCW. It processes audio input to visualize and decode these extremely low-speed transmissions, which are often imperceptible to the human ear. The software's capabilities extend to EME (Earth-Moon-Earth) operations, where its sensitivity to weak signals is particularly advantageous for detecting faint lunar reflections. The application provides a visual representation of the received signals, allowing operators to discern patterns and decode information from signals buried deep within the noise floor. Its design focuses on extracting data from signals with very narrow bandwidths and long integration times, characteristic of QRSS and similar modes. This tool is distinctively useful for experimenters and DXers engaged in challenging weak signal communication, offering a dedicated platform for modes not typically supported by general-purpose digital mode software. Its specialized focus on _Slow CW_ and _MTHELL_ makes it a niche but effective utility for specific operating scenarios.

Also known as G5RV junior the half size G5RV feature reduced dimension and multiband coverage

F6EZX presents a detailed account of constructing a compact, multi-band _Levy antenna_ for portable holiday operations, specifically addressing issues with local QRM from a previous _Deltaloop_ setup. The article outlines the design criteria, including multi-band operation on 40m, 30m, 17m, 15m, 12m, and 10m, a symmetrical configuration to reduce interference, and a low take-off angle for DX. Construction involves 2x 10.3m radiating elements and a 15.3m open-wire feeder (ladder line) with 7cm spacing, made from 1.5mm2 copper wire and foam pipe insulation spacers. Theoretical calculations, referencing F9HJ's "_Les antennes Levy_" book, guide the determination of element lengths and feeder impedance characteristics, aiming for a good match across bands with a commercial antenna tuner. Initial field tests with the _VCI Vectronics VC300DLP_ tuner showed a 1:1 SWR from 80m to 10m, with some difficulty on 17m. The antenna, mounted as a 45-degree slopper with the high point at 12m, successfully facilitated DX contacts to South America, particularly Chile and Argentina, suggesting a lower take-off angle compared to the previous Deltaloop which favored Brazil. The Levy antenna significantly reduced TVI/RFI, attributed to its improved symmetry and greater distance from the QRA. While signal reports on 15m and 20m were 1-2 S-points lower than the Deltaloop, its performance on 40m and 30m was comparable, fulfilling the design goals for a portable, low-cost, multi-band solution.

Excel spreasheet that calculate virtually every transmission line parameter that one may need. Include Length conversions, Reactance and Length of Stubs

This program descrambles band inverted encrypted transmissions, usually found on VHF/UHF. It uses a NCO (numerical controlled oscillator) to re-produce the originally inverted audio band.

Independence Missouri Police Scanner, live & recorded audio broadcasts.

Why Packet Radio? Could be, You are Missing Something Funm, by Greg Jones, WD5IVD

G8ODE 160 m Top Band Inverted L Antenna made of 33m horizontal wire in the garden

The page contains the recommended Operating Code of Practice for 6 meters band as issued by UKSMG in collaboration with other organizations. It aims to improve productivity and enjoyment for all radio amateurs using the band. The code covers topics such as inter-regional calling frequency, local band plans, DX operations, and proper operating practices. It encourages adoption by other Amateur Radio Societies to promote responsible and respectful use of the 6m band.

Dummy load described here can be used for up to 35 watts for short transmissions, and up to 25 watts for longer periods.

Broadcastify currently hosts 7,266 live public safety radio feeds, providing real-time scanner audio for police, fire, and EMS operations. The platform aggregates transmissions from various emergency services, allowing users to monitor local dispatch and response activities across numerous geographic areas. It functions as a centralized hub for streaming publicly accessible radio traffic, distinctly separate from amateur radio operations or traditional _DXing_ pursuits, focusing instead on unencrypted public safety communications. The resource primarily focuses on public safety radio systems, which typically operate on VHF/UHF frequencies, often employing trunked radio system architectures. It does not involve amateur radio bands but rather provides direct access to publicly available emergency service communications. The content is organized into categories like Top Feeds, New Feeds, and Official Feeds, facilitating navigation through its extensive catalog. Broadcastify's utility stems from its efficient aggregation and streaming infrastructure, offering a direct link to local emergency dispatch and response. The platform also details its operational mechanics and lists official providers, indicating a structured approach to content sourcing and distribution.

Over 70 international contests are supported by YPlog, a Windows-based logging and radio control program designed for amateur radio operators. This software integrates with various digital mode applications like _WinPSK_, _HamScope_, and _MMTTY_, facilitating partially automated log entry for modes such as PSK31, CW, and RTTY. It provides comprehensive logging capabilities including QSL label printing, beam headings, and dup-checking, alongside award tracking for DXCC, ITU/CQ zones, IOTA, Grid Locators, and Counties. The program offers advanced contesting features, including multi-multi or multi-2 networked operations with automatic log data sharing, multiple Cabrillo submission formats, and configurable CW keyboard layouts. Device support extends to TR-compatible CW keying, SO2R control with Top-Ten devices like the DX-DOUBLER, and internal W9XT digital voice keyer integration. YPlog is notable for its support of the _OK1RR DXCC_ country resolution files, providing a robust historical DX compendium. Beyond logging, YPlog includes two freeware utilities: one for computing design parameters for coaxial traps and another for displaying and printing azimuth and Mercator maps from the operator's QTH. The software runs on Windows 95/98/ME/NT/2K, with a recommended screen resolution of 1024x768. Registration costs **$50.00 US** to unlock all features, including full contesting capabilities and rotator control.

5 Day prediction table for ISS and find when the ISS will be visible from your QTH by N2YO

Mose Trainer by G4FON is a free windows morse code training program developed using the Koch method. Sends words simulating real morse code transmission, with QSB and QRM, allow change speed tone and many other settings. Download the kochmorsetrainer_install file and start learning Morse Code.

The Elecraft K3, a popular HF transceiver, is often benchmarked against new market entrants. This article critically compares the Kenwood TS-590S to the K3, focusing on key technical specifications and operational aspects relevant to serious amateur radio operators. The author proposes three distinct evaluation methods: a circuit diagram comparison, an independent review analysis (referencing Peter Hart, G3SJX, in RadCom), and a real-world "ear test" by experienced contest operators on 40 and 80 meters. The analysis delves into specific receiver components, including the first mixer design, RF and IF amplifier performance, and the presence of an image noise filter. It highlights the K3's switched mixer and the potential for the TS-590S to utilize similar or improved designs, such as a classic filter with enhanced selectivity. The article also scrutinizes the second mixer stage, noting the K3's SA612 chip and its associated IP3 limitations, suggesting Kenwood might achieve benefits with a different mixer architecture. Further points of comparison include DSP capabilities, where the K3's high-performing DSP with KK7P's involvement is noted against the TS-590S's potential reliance on newer IC technology but possibly less refined software. The discussion extends to DDS and PLL implementations for phase noise and spurious emissions, and the utility of a second receiver for DX chasing and contesting, acknowledging its importance for some operators while being less critical for others. The article concludes by emphasizing personal preference in equipment selection.

Reports a 404 error, indicating the requested online receiver resource is unavailable. The page explains that QSL.net hosts over 30,000 websites, each maintained by different individuals, and suggests contacting the website owner directly or performing an internet search to locate the content. It clarifies that QSL.net cannot assist in finding specific missing pages or files. The page also notes that QSL.net provides email and web services free of charge to amateur radio operators and organizations. It encourages donations to support these services, providing a link to more information on how to contribute. The content emphasizes the need for user support to maintain the platform's operations.

A homemade Magnetic Loop antenna from a spare 3m length of RG213 working from 30m to 15m with a 130pF tuning capacitor

Freeware program, special and easy to use packet program for communicating with ISS, PCSat and other 'compatible' sats. Can also be used for basic normal packet.

End-Fed Half-Wave Antennas (EFHWAs) are analyzed for their utility in portable QRP operations, emphasizing their simplicity, efficiency, and predictable radiation patterns compared to other portable antenna types. The discussion contrasts EFHWAs with vertical antennas, random length wires, and center-fed dipoles, highlighting the common pitfalls of each, such as ground system dependency for verticals and feedline issues for dipoles. The article details the electrical half-wavelength calculation using the formula L (Ft) = 468/F(MHz) and explains how EFHWAs can be resonant on harmonic frequencies, enabling multiband operation. Various deployment configurations are presented, including the inverted L, inverted Vee, sloping wire, and vertical setups, each with specific advantages for radiation angle and polarization. For instance, a vertical EFHWA offers a low angle of radiation suitable for DX contacts without requiring an extensive ground system. The resource also addresses the counterpoise requirements, suggesting a quarter-wavelength wire or connection to a metallic structure for decoupling. A schematic diagram for a simple parallel-tuned circuit tuner, based on the _Rainbow Bridge/Tuner_ design, is provided, detailing component values for 30 and 40 meters, including a 6 microhenry toroidal inductor and a 20-100 picofarad mica compression capacitor. The tuner's adjustment process for SWR matching is also outlined.

Eighteen-part tutorial on packet radio in HTML and ASCII format from Larry Kenney, WB9LOZ

PA3FWM's software defined radio (SDR) page documents his extensive hardware and software development efforts between 2004 and 2009. Initial experiments utilized a direct conversion receiver with 90-degree phase difference, feeding a PC soundcard at 48 kHz sample rate, covering 24 kHz of spectrum around a 7080.5 kHz local oscillator. This setup, similar to AC50G's QEX 2002 article, allowed for basic I/Q signal processing to distinguish signals above and below the LO frequency. Limitations included fixed crystal frequencies, 16-bit dynamic range, and narrow bandwidth. Subsequent hardware iterations aimed for enhanced performance, incorporating external 24-bit ADCs with 192 kHz sample rates, connected via 10 Mbit/s Ethernet. A **MC145170-based PLL** and programmable octave divider provided a 58 kHz to 30 MHz tuning range. The **Tayloe mixer** was employed, with differential outputs feeding a PCM1804 ADC. An ATmega32 microcontroller handled serial data conversion to Ethernet frames, though without CRC calculation due to processing constraints. Later designs integrated AD7760 2.5 Msamples/second ADCs and a Xilinx Spartan-3 FPGA, enabling direct reception of 0-1 MHz spectrum and eventually 2.5 MHz bandwidth across the shortwave spectrum. Software was refactored to use an initial 8192 non-windowed FFT for efficient high-bandwidth processing. The project culminated in a two-way QSO on 21 MHz using the developed hardware and software, demonstrating transmit capabilities with a D/A converter. The system exhibited a 2.5 MHz wide spectrum display and a zoomed 19 kHz display, capturing signals like ionospheric chirp sounders and RTTY contest activity. Challenges included noise leakage from digital circuitry and cooling for high-power dissipation components.

This DIPLEXER separates 2m from 70cm on the same coax cable, and allows to use 2 antennas over the same cable and permits transmission on one band and simultaneous receiption on the other band by hb9abx

5 Band 1/4 wave Telescopic Antenna. The 20m to 10m, antenna is simple and cheap to make, and has a performance that matches commercial antennas but at cost considerably lower. The design was purposely based on a telescoping fibre glass fishing rod as this allows it to be easily stowed away in the car.

G8ODE antenna project, where the 40m & Short 80m antenna was deployed as a sloping wire antenna using the 10M fibre glass fishing pole and a hook on the house's gutter-board

A potpourri of 160-Meter vertical antennas and modeling issues, inverted-L, 3-element parasitic array, 1/4-wavelength monopole

This article proposes a lossy transmission line model of a practical Guanella 1:1 balun that is effective for all frequencies within and immediately adjacent to the pass band

The **Black Cat CW Keyer** is a macOS application designed for amateur radio operators to transmit Morse code directly from their computer. It provides functionality for typing text to be sent, either immediately or buffered, and allows for the creation and transmission of pre-defined messages via single-key shortcuts. This software addresses the need for a flexible and accessible CW keying solution, particularly for Mac users who might find fewer dedicated ham radio applications compared to other operating systems. It integrates basic text-to-CW conversion, offering a straightforward interface for generating Morse code signals. Operators can utilize the Black Cat CW Keyer for various CW activities, including casual QSOs, contesting, or beacon operation. Its ability to buffer text allows for smoother transmission, while the single-key macro feature streamlines repetitive message sending, such as CQ calls or contest exchanges. While specific comparisons to other CW keying software are not detailed, its macOS focus provides a niche solution for Apple users. The program's utility lies in its direct approach to computer-based CW transmission, making it a practical tool for those seeking a dedicated **CW keyer** on the Macintosh platform.

Demonstrates CW Decoder Logic, a freeware application for Windows Vista SP2, 7, 8, and 10, designed to decode Morse code signals. The software incorporates an optimized 80 Hz DSP filter, enabling reception of CW signals across a speed range of 5 to 60 WPM. Key features include automatic signal tracking within a 3 KHz range, real-time speed detection, and an auto squelch function, enhancing decoder sensitivity and accuracy. The application provides station selection directly on a waterfall display and includes a "Tips" feature for word annotations. It supports sending decoded text to external logging software via UDP protocol, with a logger source code example provided for developers. Configuration options allow users to set speed limitations and customize interface elements. Released initially on October 17, 2016, with subsequent updates, the program requires Microsoft .NET Framework 4.5 or higher. Changelogs detail improvements such as increased program stability, code optimizations for speed, and fixes for display issues across different Windows versions.

Catalogs over 9,300 radio transmissions heard within Finland, providing a detailed frequency database for Finnish radio enthusiasts. The resource lists frequencies for various services, including maritime VHF channel 16 at **156.800 MHz**, RHA68 channel 16 at 71.100 MHz, and _MIL AIR_ frequencies like 251.100 MHz. It also documents air traffic control frequencies, such as 123.775 MHz for Area Control and 127.000 MHz for Approach Control, alongside frequencies for Finnish Air Force operations at 140.550 MHz. The database includes entries for commercial shared channels at 170.450 MHz and 458.250 MHz, as well as specific local business frequencies like 443.125 MHz for Sale Merimasku. Shortwave broadcast entries are also present, noting stations like BBC at 6.035 MHz from Tashkent and AIR Akashvani Ext.Sce at 11.900 MHz from Bangalore. The site organizes its extensive listings by categories such as "Liikenne" (Traffic) with 2397 entries, "Radioamatoori" (Amateur Radio) with 781 entries, and "Yle" (General) with 2305 entries. The database was last updated on 26.2.2024, reflecting ongoing maintenance and additions to its comprehensive collection of Finnish radio spectrum data.

Antenna Warehouse provides a range of certified quality wire products for amateur radio and general communication applications. Their inventory includes Francis antennas, known for their robust construction, alongside the versatile Select-A-Tenna series. The company also stocks Solarcon 10/11 meter base antennas, catering to specific band requirements for 27-28 MHz operations, and various Wilson antenna models. Beyond product sales, Antenna Warehouse offers services such as antenna tower installation, repair, and removal. These services support the complete lifecycle of antenna systems, from initial setup to maintenance and decommissioning. The product selection emphasizes components for both fixed station and mobile installations.

Explains the Federal Communications Commission (FCC) vanity call sign program, outlining the specific rules and procedures for amateur radio operators in the United States to obtain a personalized call sign. It details the eligibility requirements based on license class, the application process using FCC Form 605, and the various group formats (e.g., _1x2_, _2x1_, _2x2_) available to different license classes, such as Extra and Advanced. The resource clarifies the priority system for vanity call sign requests, including previous holders and close relatives, and discusses the typical processing times for applications. It also provides insights into how the FCC assigns available call signs and offers practical advice for increasing the likelihood of securing a desired call, referencing the _ARRL Letter_ for updates.

Sohl List of English language transmissions

Ground tracks are the trace of the satellite's path over the ground. Amsat, ISS, geosynchronous satellites, navigation satellites, weather satellites, Iridium satellites, visible Satellites. Requires Java

The purpose of the APRS-Beacon is to provide simple APRS-compatible position beacons for up to three Objects. It is designed to 'stand alone' and does not monitor other traffic on the frequency. It can use a single-port TNC (in 'native' mode), a single- or dual-port TNC in Kiss mode or the AGW Packet Engine in order to transmit on up to four radio ports.(When running with AGWPE, APRS-Beacon will also work with Windows 2000)

The purpose of this web page is to try to investigate the ICOM IC-746PRO Dead TX problem reported by many radio amateurs through out the world; and unfortunately not properly taken care of by ICOM. If you are the owner of either the ICOM IC-746PRO or the IC-7400 you may already have experienced the Dead TX Issue. If not you may sooner or later.

The document details the optimization and construction of the _Maria Maluca_ antenna, a compact 6-band (20m-6m) directional beam. It presents a comparative analysis of shortwave antenna principles, highlighting the efficiency gains achieved by using an open feeder line and tuner as a resonant unit, contrasting this with the losses associated with traps or capacitive loads in multiband antennas. The resource specifically revisits an older South American 2-element design for 10, 15, and 20 meters, applying modern NEC-based software to develop a six-band version. Performance data is meticulously tabulated, showing impedance, free space gain, gain at 12m height, elevation angle, and front-to-back (F/B) ratio for each band from 20m through 6m. For instance, on 15m, the antenna achieves 5.1 dBd free space gain and 13.72 dB F/B ratio. The construction section provides practical guidance on element assembly using aluminum pipes and hose clamps, detailing the use of a heavy-duty glass fiber reinforced polyamide rod for electrical separation and bending strength. It also specifies the use of 450-ohm _Wireman_ line CQ 552 for the transmission line. The document includes diagrams for rod fixing, an air-wound balun, and a vertical elevation diagram for the 15m band, illustrating its DX qualification. It also discusses the antenna's suitability for portable and expedition operations, noting its compact transport dimensions (max 1.50m length, 12 lb weight) and quick assembly time (under 15 minutes). The author, Dipl.Ing. Helmut Oeller, DC6NY, is identified as a source for material kits.

Sound samples of the transmission modes recorded at 11025 samples per second, mono and the message in all of the samples is the same: "the quick brown fox jumps over the lazy dog 1234567890".