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Query: Frequency
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IRAQ War Military HF freqs, Aero HF frequencies and Shortwave Broadcast schedules of interest
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Log4OM is a free logging software designed for amateur radio operators who require an integrated environment for station management and QSO logging. It is widely used by DXers due to its strong database capabilities and its integration with common online services. The program uses a structured SQL database and supports large logbooks without noticeable performance degradation. One of its key features is **CAT Control**, which allows direct communication with many transceivers for automatic frequency and mode detection. The **DX Cluster Client** provides real-time spotting with filtering and band/mode tracking, helping operators quickly identify new DX opportunities. Log4OM integrates with several external confirmation systems. Built-in support for **Logbook of The World (LoTW)** and **eQSL** allows automatic upload and download of confirmations. The software also includes **Award Tracking**, enabling operators to monitor progress toward DXCC and other award programs directly from the log. Additional capabilities include **Callbook lookup** via services such as QRZ, **ADIF import/export**, and customizable **QSL management** for both electronic and paper cards. The interface is modular, with panels that can be arranged depending on operating preferences. Log4OM does not include integrated digital mode engines, so digital operation normally relies on external programs such as WSJT-X or FLdigi connected through standard interfaces. Overall, Log4OM provides a comprehensive logging environment suitable for both casual operation and serious DX chasing, with a feature set comparable to many commercial logging applications.
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Demonstrates _Freq51_ and _Specgrm2_, two analysis programs from the Biomedical Ultrasonics Laboratory at the University of Michigan, available for DOS or Linux. The _Spectrum Analyser (Freq51)_ provides power spectrum levels as a function of frequency, configurable for absolute values (e.g., dB re 1 volt) with sound card calibration. _Spectrogram (Specgrm2)_ generates a real-time, full-screen spectrogram (sonagram) with various color options. These programs analyze incoming signals in real time, not stored files, and offer extensive settings for sampling rate, FFT points, and averaging time, making them highly versatile for acoustic analysis. The DOS version of _Freq51_ and _Specgrm2_ can operate under Windows 95, requiring users to configure sound card switches via a text file. The resource also briefly mentions other acoustic analysis software like Gianni Pavan's DOS-based bioacoustic tools, _Gram_ by R.S. Horne for Windows, _SASLab_ (Light and Pro versions), _Cool Edit_, and _GoldWave_, providing a comparative overview of available tools for real-time and file-based spectral analysis and waveform manipulation.
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The project details modifications to an ARK-40 QRP CW transceiver kit, specifically replacing its original thumbwheel frequency selectors with a **BASIC STAMP BS-II microcontroller** and an optical shaft encoder. The redesigned control circuitry outputs a BCD code to the ARK-40's synthesizer, enabling more convenient knob-type tuning. This modification significantly alters the user interface, moving from discrete frequency selection to continuous tuning. Operating frequency is presented on an LCD readout, offering two distinct display modes: a "bandspread dial" mode that simulates an analog dial scrolling across the display in 1 kHz increments, and a conventional digital readout with 100 Hz resolution. Pushing the main tuning knob toggles between these modes, providing both rapid band traversal and fine-tuning capabilities. The software for the BASIC Stamp is written in P-Basic, addressing the challenge of accurate analog dial simulation. Physical modifications include fabricating a custom PC Board for the STAMP, mounting it with an L-bracket to the optical encoder, and creating a new front panel. The front-mounted speaker was relocated to accommodate the new tuning knob and display, transforming the **ARK-40 transceiver** into a more user-friendly rig with its built-in CW keyer and 5 watts of power.
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Over 30 distinct shortwave (SW) receiver models are reviewed, offering insights into their performance, features, and user experiences. These evaluations, contributed by readers of the Usenet newsgroup **Rec.radio.shortwave**, cover a wide array of portable and tabletop radios, including popular units like the Grundig YB-400, Sony ICF-SW77, and various Realistic DX series models. Each review details aspects such as frequency range, tuning steps, SSB functionality, antenna performance, and construction quality, often comparing them to other receivers or ham transceivers like the Icom 725. For instance, the Grundig YB-400 review highlights its 144-30000 kHz AM/SSB coverage, direct keypad entry, and 40 station memories, noting its useful narrow bandwidth and tone switch for adjacent signal separation. It also discusses the **SSB mode** stability and the limitations of its 1 kHz frequency resolution for precise zero-beating. The review further details antenna performance, including the effectiveness of the built-in whip, the provided 7m reel antenna, and the potential for overload with larger outdoor antennas. Other reviews delve into specific issues, such as the Sony ICF-SW77's frequency display inaccuracies and timer malfunctions, or the Realistic DX-342's compact size and surprisingly good MW DXing capabilities despite its analog tuning. The collection provides practical, user-generated feedback on sensitivity, selectivity, audio quality, and ergonomic features, helping shortwave listeners understand the real-world performance and quirks of these receivers.
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Antenna for GSM, CB, marine, VHF/UHF, HAM and high frequency 1,9/2,4GHz
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How to make a simple but effective Slim Jim antenna. It includes a calculator to work out all the mesurements for the frequency you require.
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Online radio planning system, allow you to generate accurate radio frequency predictions for anywhere on earth
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The directory lists several files, including `_template1.html` and `_template2.html`, last modified in 2006 and 2004 respectively, indicating a historical web project. Key scripts like `hfcc_cfm.pl` and `index.cgi`, updated in 2011, suggest a **CGI-based application** for searching shortwave broadcast schedules. The presence of `_template1.tpl` and `_template2.tpl`, both modified in 2015, points to a templating system for dynamic content generation. The file `hfcc_create-fill_mys..>` (likely `hfcc_create-fill_mysql.pl`) implies interaction with a database, possibly MySQL, for storing and retrieving **HFCC (High Frequency Co-ordination Conference)** schedule data. The `lang.cgi` script, last updated in 2002, suggests early support for multilingual interfaces or language-specific content delivery. The `q.txt` file, a small 804-byte text file, could be a query log or a simple data file. The overall structure indicates a system designed to process and present shortwave broadcast information, likely by querying a database of scheduled transmissions on various HF frequencies. The file modification dates suggest the project was actively developed and maintained over a period spanning more than a decade, with core components last updated around 2011 and templates in 2015.
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Optimal Working Frequencies (MHz) for High Frequency (HF) / Shortwave Radio. By region, updated monthy.
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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.
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Presents a crystal-controlled CW transmitter design for the 40-meter band, delivering 5 to 7.5 watts output power. The circuit innovatively employs an _IRF510_ power MOSFET in the final amplifier stage, diverging from conventional bipolar transistors. This design offers high gain, nearly 90% efficiency, and robust resistance to high SWR, allowing 30-second key-down operation into an open circuit without damage. A critical aspect is the precise adjustment of the MOSFET gate bias via a 10K trimmer pot, _R10_, to maintain quiescent current between 5 and 10 mA, preventing thermal runaway inherent to bipolar devices. The prototype was constructed on a _Radio Shack universal board_ and achieved immediate operational success. The design requires a 15-volt Zener diode to protect the MOSFET gate from overvoltage. Component sourcing information is provided, including specific crystal frequencies (7.040 MHz or 7.122 MHz) available from _Dan’s Small Parts & Kits_ or Doug Hendricks. The fixed frequency can be slightly adjusted with a trimmer capacitor. A complete bill of materials, including resistor values, capacitor types, toroid specifications, and transistor part numbers, is detailed, alongside a clear schematic diagram.
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Mars Mod for Yaesu FT-450 extending frequency range: 1.8-30 MHz
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Contains a PC sound card based signal generator. It can generate functions, multitones, arbitrary waveforms, burst tones, MLS, DTMF, musical scales, white noise and pink noise, and frequency/amplitude sweep. Fully functional free trial downloadable.
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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.
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The KD6WD Moxon Antenna Project details the construction of 50-ohm two-element wire beam antennas, specifically Moxon rectangles, for the 10, 15, 17, and 20-meter bands. It utilizes AC6LA's software for critical measurement calculations (A-E) based on center frequency and wire size. Construction involves 16-gauge silver-coated copper wire, 16-foot telescoping fiberglass crappie fishing poles as spreaders in an "X" configuration, and various hub designs including aluminum tubing or PVC joints. A 1:1 current balun is used at the feedpoint, with wire nuts for connections, often achieving a 1:1 SWR across the design band. The project highlights practical applications, such as running a kilowatt into the antennas for greyline DX contacts, consistently yielding excellent signal reports. Comparisons to quad loops show 4 to 5 S-unit improvements in both receive and transmit. The Moxon design, according to L.B. Cebik's analysis, offers superior forward gain and front-to-back ratio among wire beams. The author notes a "DX-Vane" effect where a freely suspended Moxon automatically points to the strongest DX signal. Attempts at dual-band operation (17/20 meters) with a single feed were unsuccessful, reinforcing the Moxon's monoband nature, with EZNEC plots provided for a 17-meter Moxon at 30 feet.
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A very easy to use program to decode DTMF dial tones found on telephone lines with touch tone phones. The DTMF Decoder is also used for receiving data transmissions over the air in amateur radio frequency bands.
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Selecting an appropriate antenna system for shortwave broadcasting involves evaluating various types based on performance, cost, and operational parameters. This resource details the critical specifications for broadcast antennas, including average and peak power ratings, directivity, takeoff angle (TOA), horizontal beamwidth, and gain, emphasizing that a 100-kW transmitter requires an antenna rated for 150 kW average and 400 kW peak. It clarifies that low TOA signals travel thousands of kilometers, while high TOA is for local coverage, and nearly all modern shortwave broadcast antennas are horizontally polarized. The article explores specific antenna types, such as Log-Periodic Antennas (LPAs), which offer wide frequency ranges (e.g., 2-30 MHz) and directional patterns with 11 dBi gain, costing from $20K to over $100K for multi-curtain versions. Dipole arrays, also known as curtain antennas, are prevalent in international broadcasting, featuring steerable beams (±15° and ±30°) and mode-switching capabilities to alter TOA, with high/low pairs costing over $1 million. Fan dipoles are noted for omnidirectional patterns, smaller size, and lower cost for low-power applications, while rhombics, though simple, require resistive termination and incur several dB of I2R losses. Balun considerations are crucial, as most communications baluns are not rated for the higher average and peak powers of AM broadcast transmitters. Modern shortwave antennas utilize durable materials like Alumoweld wire rope for radiators and support elements, avoiding copper, fiberglass, or materials prone to stretching or deterioration. Feeder systems for high-power stations often require tapered-line baluns to convert 50-ohm unbalanced power to 300-ohm balanced for connection to the antenna.
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Macintosh audio spectrum analyzer that allows the user to view live audio in a standard frequency plot, a stereo oscilloscope view and a waterfall display
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BeaconSee shows you, in real time, worldwide HF band openings on your PC. Analyses the audio signals from your radio, which is tuned to the NCDXF IARU HF beacon network and shows you the signal strength received from each of the 18 beacon transmitters as a plot of frequency spectrum against time.
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Facilitates efficient logging of amateur radio contacts, offering a robust solution for hams managing their station activities. The software integrates _CAT control_ capabilities, allowing direct interfacing with popular transceivers from manufacturers like Yaesu, Icom, and Kenwood. This feature streamlines the logging process by automatically capturing frequency, mode, and other QSO details directly from the radio, reducing manual entry errors and improving operational efficiency during contests or DXing. _HAM-LCT_ includes a comprehensive database, enabling users to store and retrieve contact information, QSL data, and other relevant details for each QSO. The program supports various operating modes and provides tools for searching and filtering log entries, which is beneficial for award tracking and station analysis. Its design focuses on providing a user-friendly interface for everyday logging tasks. While the original author, _HB9CQV_, has discontinued development of HAM-LCT in favor of a newer logging application, this version remains available as a functional freeware option for Windows users seeking a dedicated logbook with integrated rig control.
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Description of PSK31, mailing list, frequency for QSO
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This article addresses the subject of obtaining the best signal transfer from an antenna to the typical 50-ohm receiver input over a wide frequency range, with emphasis on medium-wave (500 - 2000 kHz), encompassing the standard AM broadcast band and the 160-m amateur band.
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Database system with 60000 frequencies, powerfull 3D MUF/LUF-propagtion software and full copntrol of several receivers
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Free windows program to calculate magnetic loop antenna.This small loop antenna calculator allow to determine capacitance and voltage based on Loop circumference, desired resonant frequency, conductor diameter and the operating power
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RT Systems provides programming software for Windows operating systems, supporting a wide range of amateur radio transceivers, scanners, and receivers from manufacturers like Icom, Yaesu, and Kenwood. The software facilitates memory management and radio settings configuration, often surpassing OEM software in user-friendliness and functionality. Their **USB programming cables**, featuring **FTDI chipsets**, are noted for reliable operation, even in virtualized environments like Windows ARM on a Mac, where OEM cables might fail. Users report that RT Systems software simplifies the often complex process of radio programming, making it less arduous than manual entry. The availability of integrated frequency databases is a significant advantage. The software and cables are frequently cited for their long-term reliability, effective customer support, and thoughtful hardware design, which collectively address common real-world programming challenges for various radio models, including the Icom ID-880H and Anytone 878.
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An old satellite frequency list from 3 to 8475 Mhz dated 1996
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RadioReference.com, scanner frequency and radio communications reference source, with complete conventional frequency assignments, trunked radio system information, frequencies, and talkgroups, FCC License assignments and maps, 10-Code Lists, agency maps, files, downloads, links, and detailed agency information for most public safety, military, and local government activities.
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The radio spectrum in usa, PDF File representing the united stares frequency allocations in graphical mode, dated 2003
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What is NVIS Near Vertical Incident Skywave. This article on NVIS (Near Vertical Incidence Skywave) explores its role in short-range HF communication, covering 0-200 miles. NVIS utilizes antennas with high radiation angles and frequencies below the ionospheric critical frequency to achieve reliable local contact. He details optimal antennas, like low dipoles, and practical tips for maximizing NVIS performance, emphasizing its advantages such as reduced noise and independent operation without repeaters. However, challenges include frequency sensitivity and the need for appropriate antenna setups at both ends for effective communication.
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The **NW3Z** optimized wideband antenna designs, originally presented at Dayton 2001, detail Yagi configurations for the 20-meter, 15-meter, and 10-meter amateur radio bands. This resource provides access to the design files, likely containing critical parameters such as element spacing, element lengths, and boom dimensions, which are essential for replicating these directional antennas. The designs focus on achieving wide bandwidth, a desirable characteristic for contesters and DXers operating across a significant portion of each band. The content specifically references "nw3z-Antenna-DesignsDownload," indicating that the core information is available as a downloadable file, presumably in a format suitable for antenna modeling software or direct construction. Such files typically include **NEC models** or similar data, allowing for performance analysis and optimization before physical construction. The emphasis on "optimized wideband" suggests design considerations for SWR bandwidth and gain characteristics over a broader frequency range than typical narrow-band Yagis. The resource serves as a direct source for specific, proven antenna designs from a known amateur radio antenna designer, offering practical data for hams interested in building high-performance Yagi arrays for HF.
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Illustrates the fundamental principles of radio repeater operation, detailing how different duplex configurations overcome signal limitations in varied terrains. It begins by contrasting _simplex_ communication, where all units share a single frequency, with more complex systems designed for extended range and specialized applications. The resource systematically presents each mode, from basic base station setups to advanced multi-frequency configurations. The content specifically covers hemi-duplex systems, often used in commercial dispatch, where the base station transmits on one frequency and mobiles on another, without rebroadcast. It then progresses to semi-duplex repeaters, the most common type in amateur radio, which automatically retransmit received signals on a different frequency. The explanation extends to demi-duplex and hemi-demi-duplex systems, which incorporate multiple control links for enhanced operational flexibility and secure communications, as seen in public safety applications. Finally, the resource clarifies full-duplex repeater systems, exemplified by cellular networks, where simultaneous two-way communication is achieved through distinct transmit and receive frequencies for each direction. The visual aids, including **9 distinct figures**, effectively demonstrate the signal paths and frequency assignments for each operational mode, providing a practical understanding of repeater architecture.
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The resource details the construction and performance of a dual-band 40/30 meter _Moxon_ antenna, evolving from an initial single-band 30-meter design that failed in a storm. It specifies materials such as four 10-meter fishing rods, galvanized iron TV antenna support pipes, 1mm diameter PVC-covered copper wire, and a piece of 75-ohm TV satellite cable for feedline. The document outlines the iterative design process, including initial resonance measurements of 9.9 MHz for 30 meters and subsequent recalculations to shift the center frequency by 300 kHz using _Moxon software_. Initial testing on a roof yielded SWR readings of 1.4:1 at 7.200 MHz and 1.5:1 at 10.280 MHz. After installation atop a 30-meter tower, the final SWR measurements were 1.1 at 7.130 MHz and 1.4 at 10.230 MHz, with a notable 30 dB front-to-back ratio on 40 meters. The 30-meter performance, while good, showed a front-to-back ratio of approximately 15 dB, suggesting a slightly high resonance. The antenna's placement on a 700-meter hill, with a significant ground drop in certain directions, is noted as a potential factor in its excellent DX performance, enabling daily contacts with the USA West Coast on 30 and 40 meters with 100 watts.
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RTTY press services in english sorted by frequency
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Over 45 years of amateur radio experience inform the homebrew projects detailed on this personal website, with a particular focus on microwave frequencies. The site showcases a 24 GHz transverter and a more recent 47 GHz transverter, demonstrating practical construction techniques for extreme high-frequency operation. These projects often involve custom circuit design and careful component selection to achieve stable performance at millimeter-wave bands. Key projects include a _harmonic converter_ for frequency measurement and a tracking spectrum analyzer, essential tools for microwave experimenters. The site also documents a CW sidetone generator and a TX/RX sequencer, illustrating fundamental building blocks for radio equipment. Details on a digital frequency meter and an S-meter/dBm meter provide insights into test equipment construction. Specific achievements, such as a **24 GHz** tropo QSO with DK3SE in 2021, highlight the operational success of these homebrewed systems. The content reflects a long-standing dedication to self-sufficiency in amateur radio, providing practical examples for those interested in building their own gear.
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Radio Scanners Uniden Bearcat, Antennas, CB_Radios, Ni-Cad Batteries, Frequency Books, Accessories, Power Supplies and Cords, FM Two Way Radios, and other Related Merchandise
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Demonstrates a **DX cluster** web service providing real-time amateur radio spot reports, propagation information, and solar data. The platform integrates features such as a gray line map, **DXCC** tracking, and a personal logbook, allowing users to manage their confirmed entities and contacts. It supports various bands from 160m to 70cm, including specific filters for modes like FT8/FT4, and offers both web and Telnet access for spotting and monitoring. The service provides graphical representations of spot reports, detailing activity across different frequency bands and modes (CW, SSB, digital). Registered users gain access to advanced functionalities, including personalized filters and tools for calculating DXCC status. The platform also includes a classifieds section and options for mobile access, catering to a broad range of amateur radio operators interested in DXing and contesting.
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Automatic Link Establishment (ALE) is a digital signaling protocol enabling HF radio stations to automatically establish communication links, crucial for emergency and disaster relief operations. HFLINK serves as a central international resource for ALE High Frequency Communications, HF Selective Calling (SELCALL), and general HF interoperability. The platform provides extensive information on ALE operation, including frequency networks, band plans, and software like _PCALE_ for amateur radio integration. It also documents significant events such as the _HF Interoperability Exercise (HFIE)_ and the _Global Simulated Emergency Test (GlobalSET)_, which allow ham operators to gain real-world experience in interoperable HF communications, often using specific frequencies like the USA 5 MHz ALE simplex frequency 5371.5 kHz USB. The site features articles on antenna types popular among ALE users, such as autotuners and broadband antennas like the _T2FD_ and the Broadband Butterfly Terminated Dipole (BBTD).
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MoxGen is a **Windows** application designed to calculate dimensions and generate antenna model files for 50-ohm **Moxon Rectangle** antennas. Users input the desired design frequency in MHz and the wire size (AWG or diameter in inches/mm), and the software outputs the precise element lengths, spacing, and overall dimensions required for construction. It also creates a .maa file compatible with EZNEC, enabling further analysis and optimization of the antenna's performance characteristics. The software provides a visual representation of the Moxon rectangle, displaying key parameters such as gain, front-to-back ratio, and SWR at the design frequency. This allows radio amateurs to quickly assess the potential performance of their proposed antenna before physical construction. The generated EZNEC model facilitates detailed pattern analysis, impedance matching, and interaction with surrounding structures, proving useful for both initial design and fine-tuning.
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These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.
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Table of frequency allocations international & US by Bill McFadden
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Professional antennas in MF, VHF, UHF and SHF frequency range for military applications, civil-professional market, mobile communications, radioamateurs and antennas for special applications - EMC, radiomonitoring, etc.
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Input the desired resonant frequency and it will calculate lenght in inches feet and meters
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A PIC16F876 microprocessor-based digital SWR/WATTmeter project provides automatic operation across the 1.8 to 60 MHz frequency range. This design displays both SWR and P.E.P. power values, incorporating a bar graph on the second LCD line for instantaneous power tracking. The directional coupler utilizes a single-wire coil on a ferrite FT50-43 toroid, balanced with a 60 pF trimmer, and employs 1N5711 Schottky diodes for detection, ensuring linearity and a power range of 5 to 120 W. The software, developed by IW3EGT, compensates for diode voltage drop for precise readings, updating power every two seconds for stable display of modulated carriers, while the bar graph updates ten times per second for near real-time feedback. Calibration involves two phases: adjusting the directional coupler for minimum SWR on a 50-ohm dummy load at 28 MHz, and calibrating the microprocessor system by inputting a calculated power value (Power (Watt) = (Vout + 0.5)^2 / 100) at 14-21 MHz. The project includes PCB layouts for both the directional coupler (two-layer copper board) and the PIC module (single-sided), with specific instructions for component placement and shielding to prevent RF interference. The design allows for modification of power reading capability by varying the number of turns in the coupler coil, catering to different power levels.
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gMFSK, a Gnome Multimode HF Terminal, provides a comprehensive software solution for digital conversational modes on HF bands within Linux and Unix-like operating systems. The application facilitates sending and receiving various digital modes, including MFSK (MFSK16 and MFSK8), RTTY, THROB (1, 2, and 4 throbs/sec), PSK31 (BPSK and QPSK), PSK63, and MT63. It leverages the computer's soundcard for transceiver interfacing, performing all digital signal processing on the main CPU. The software features a multimode waterfall display incorporating waterfall, spectrum, and scope views, enabling _point-and-click tuning_ of decoded signals. Remote logging capabilities are supported via SysV IPC, with integration for logging applications like Xlog. PTT control is managed through serial or parallel port lines, and rig control is implemented using the _Hamlib_ library, allowing for real-time frequency display and transceiver manipulation. Fixtext macros can incorporate variables and command-line output. Distributed under the GNU General Public Licence, version 2, gMFSK requires Gnome libraries and FFTW 2.x libraries for operation, even without a full Gnome desktop environment. The software's design ensures compatibility with any soundcard supported by the operating system.
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Details the construction of a portable _Moxon_ antenna optimized for the 2-meter band, utilizing readily available materials like 6.5 mm aluminum elements and a 15x15 mm TV boom. The design emphasizes ease of assembly and portability, making it suitable for field operations. Performance specifications derived from MMANA modeling indicate a forward gain of **6.3 dBi** and a front-to-back ratio of **15 dB**. Lateral attenuation is reported at 40 dB, with a minimum SWR of 1.1 at 144.300 MHz, confirming efficient operation within the target frequency segment. The antenna is lightweight at 500 grams, quickly assembled in approximately two hours, and disassembles into a compact 40x15x8 cm package. Direct feeding with RG-58 C/U or KX-15 coaxial cable via a BNC connector simplifies deployment.
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Active antenna with a frequency response that is flat from 5kHz to over 30MHz
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A Portable Low Frequency Antenna Analyzer, For those of us who like to play with antennas on the ham bands, one of the handiest tools to have around the shack is an "antenna analyzer". These gadgets combine a signal generator and standing-wave ratio (SWR) sensor in a small battery-powered unit.