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Query: communication
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- Radio Scanning > Aeronautical
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- Software > Digital Voice
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- Technical Reference > DTMF
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- DX Resources > Nets > Emergency Nets
- Operating Modes > FT8
- Technical Reference > Ham Radio Go Kits
- Manufacturers > Transceivers > Icom
- Ham Radio > Clubs > North America > USA > Idaho
- Ham Radio > Clubs > North America > USA > Illinois
- Manufacturers > Interfaces
- Ham Radio > Clubs > North America > USA > Iowa
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RTTY by WF1B integrates terminal program functionalities with contest logging features, a design choice that proved highly effective in the author's field operations. It specifically supports a range of popular TNCs, including the AEA PK-900, MFJ-1278, AMT-1, and the HAM PCI4000/4100/3000 series, among others. This broad compatibility allows operators to leverage existing hardware investments while engaging in **RTTY** contesting. The software's dual nature streamlines the workflow for digital mode enthusiasts, eliminating the need to switch between separate applications for basic communication and contest participation. This integration is particularly beneficial during high-intensity **contests** where rapid logging and message exchange are critical. WF1B's creation addresses the practical needs of amateur radio operators seeking a dedicated solution for RTTY digital mode activities.
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Repeaters, transmitters and receivers manufacturer for ham radio and commercial applications
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Article by DK5WL describes a multi-band DX antenna for the 160m-40m amateur radio bands with low visibility but great performance for long distance communication.
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The Radio Attic serves as a dedicated online marketplace for **antique radios**, offering a platform for enthusiasts to buy and sell vintage communication equipment. The site features classified advertisements, each displaying full-color photographs of the radio, a detailed description, and a direct link to the seller's email address. This structure facilitates direct communication between buyers and sellers, as transactions are handled independently, not by the webmaster. Listings are categorized by style, manufacturer, and year of manufacture, including models from Admiral, Airline, Atwater Kent, Crosley, Emerson, Fada, General Electric, Philco, RCA, Silvertone, and Zenith. The platform also tracks new additions, with 49 radios and 6 books added in the past 30 days, and highlights recently sold items, totaling 157 radios this year. Beyond sales, the site provides resources like a price guide and information on upcoming swap meets, such as the Southeastern Antique Radio Society's Spring Swap Meet in Forsyth County.
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This document by W4HM explains the construction and usage of a 160 meter balanced coaxial receiving loop antenna, which can be easily adapted for the 40 and 80 meters bands. The content provides detailed instructions on building the antenna, its advantages, and how to optimize its performance for amateur radio operations. It is a valuable resource for radio amateurs looking to improve their receiving capabilities and enhance their overall radio communication experience.
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Over 65 years of radio manufacturing experience underpins Icom's extensive product line, ranging from handheld VHF/UHF transceivers to sophisticated HF base stations. The company's global website serves as a central hub for product information, technical specifications, and support resources for its diverse range of communication equipment. Hams can explore detailed specifications for popular models like the _IC-7300_ and the _IC-9700_, alongside commercial and marine radio offerings. The site provides access to product catalogs, firmware updates, and user manuals, ensuring operators have the necessary documentation for their Icom gear. Information on new product releases and technological advancements in radio communication is regularly updated, reflecting the company's ongoing commitment to innovation in the amateur radio market. Icom's presence extends across various radio segments, including D-STAR digital voice, marine, avionics, and land mobile, demonstrating a broad engineering capability beyond just amateur radio.
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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.
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The AZIMUTH program plots a world map in either azimuth (beam heading) or Mercator projections. If you specify your home location in latitude and longitude, the azimuth projection is centred on your location. The Azimuth map program can display Maidenhead grids - this is useful for 6m, 2m, and UHF DX communication display. Various features of the map are: Azimuth or Mercator projections , Maidenhead grid display, Simple map zooming, Print maps with adequate resolution up to one meter sized map
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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.
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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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DarwinPsk is free to licensed ham radio operators and is a great application for PSK and RTTY communications under MacOSX
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Presents the design and construction details for a VHF bicycle-mobile antenna, originally published in QST. The antenna utilizes a modified _Arrow J-Pole_ design, adapted for portable operation on a bicycle frame. Performance characteristics include a reported **1.5:1 SWR** across the 2-meter band, demonstrating effective impedance matching for typical handheld transceivers. Construction involves readily available materials, emphasizing lightweight components suitable for mobile deployment. The document provides a parts list and step-by-step assembly instructions, detailing the radiator and ground plane element lengths for optimal resonance at 146 MHz. Mechanical considerations for mounting on a bicycle are also addressed. The resource covers practical aspects of integrating the antenna with a bicycle, including cable routing and securing methods. It offers insights into achieving reliable VHF communications while operating in a mobile, low-power environment, making it relevant for field day activities or casual portable operation.
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"ARES trains and organizes Hams to provide emergency communications to ""Served Agencies"" such as FEMA, National Weather Service, Red Cross, Salvation Army, Hospitals, and others. This site describes ARES goals and methods and structure."
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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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HamFax is an application for sending and receiving facsimiles in amateur radio and for receiving public facsimile broadcasts like weather maps. Supported interfaces are sound cards and the SCS-PTCII from Special Communication Systems.
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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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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.
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Manufacturer of communications antennas, bandpass filters, RF combiners, receiver multicouplers, diplexers, duplexers, RF connectors, RF circulators, RF isolators, RF couplers and SWR meters
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The K5OE 2-meter vertical mobile antenna design, detailed in this resource, employs a 3/8-wavelength vertical section complemented by four shortened radials, forming an off-center-fed vertical dipole. This configuration creates a self-contained lower half, enhancing efficiency compared to traditional 1/4-wave monopoles relying on vehicle bodies for a ground plane. The article specifies construction using PVC components, 10-gauge insulated wire for elements, and provides precise dimensions in both inches and centimeters for the 25-3/16" (64 cm) vertical and 7-3/16" (20 cm) radials. Performance data indicates an honest 3 dBi of gain at 6 feet elevation (2 dBi free-space), with a pattern favoring the horizon, suitable for Low Earth Orbit (LEO) satellite communications. At 20 feet high, the same antenna exhibits almost 6 dBi of gain, with a nominal 50 Ohm feedpoint impedance at 146.850 MHz. Tuning instructions involve trimming element lengths, with the author achieving a 1.2:1 SWR by pruning the mast to 24-3/4" and radials to 7". The resource highlights the antenna's effectiveness for mobile LEO satellite uplinks, particularly at low elevations, and its suitability for fixed, mobile, or portable operations. The flexible wire elements allow for easy folding, making it a practical choice for backpacking. The original design by K5OE was previously hosted on aol.com.
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KaWin is a Windows software that supports multiple Kantronics TNCs and multiple radio transceivers with an intuitive, graphical interface, setting a new standard of performance for digital radio communications. Software is not supported anymore.
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Presents the product lines and corporate information for Japan Radio Company (JRC), a long-standing manufacturer of radio communication equipment. The company's offerings span various sectors, including marine, land, and aviation communication systems, alongside their historical contributions to amateur radio with notable **HF transceivers** and **shortwave receivers**. JRC emphasizes its technological expertise in areas such as radar, satellite communication, and network solutions, contributing to global safety and security infrastructure. The resource details JRC's commitment to leveraging its accumulated knowledge and experience in information and communication technology. While the primary focus has shifted towards commercial and governmental solutions, the legacy of JRC's amateur radio products, such as the JRC JST-245 transceiver and the NRD-525 receiver, remains significant within the ham radio community, known for their robust build quality and performance.
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The ITU and CQ Zones Map is a printable two-page PDF provided by Icom, displaying the world divided into ITU and CQ Zones. The purpose is to assist radio amateurs in identifying and understanding these zones for communication purposes.
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JTDX is an open-source software application for amateur radio weak-signal digital communication. It supports digital modes including FT8 and JT9. The software operates on _Windows_, _Linux_, and _macOS_ platforms. JTDX is designed for improved decoding of weak signals, a function also performed by WSJT-X and MSHV. The software facilitates weak signal decoding and transmission. It integrates with logging systems for QSO management and can automate tasks such as call management and remote RTX control. JTDX is utilized in contexts such as DXing and contests. DXZone Focus: FT8 | JT9 | Weak Signal | Multi-platform
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Kv5r Understanding NVIS Antennas and Propagation. This article is not intended to be a complete primer on HF radio propagation or emergency communications.
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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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A 2-meter Turnstile antenna, detailed for amateur satellite communication, offers a straightforward build for those looking to engage with orbiting transponders. The author, WB8ERJ, shares his personal design and construction methods, emphasizing the antenna's simplicity and effectiveness for LEO (Low Earth Orbit) satellite work. This design provides a circularly polarized signal, crucial for mitigating _Faraday rotation_ and signal fading often encountered with linearly polarized antennas when tracking satellites. Construction involves readily available materials like PVC pipe and copper wire, making it an accessible project for many hams. The article includes practical advice on element spacing and feed point considerations, drawing from the author's hands-on experience in the shack and field. It highlights the antenna's utility for receiving signals from various amateur satellites, including the popular AO-91 and AO-92. The Turnstile's inherent omnidirectional pattern in the horizontal plane, combined with its circular polarization, yields consistent signal reception, often resulting in **stronger decodes** and **more reliable contacts** compared to basic dipoles or verticals.
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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.
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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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Live railroad scanner radio communications. Offer forums and links to several live railroad radio feeds
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W5ALT Indoor Vertical Antenna is a base loaded vertical antenna that can be tuned on almost all HF bands by adjusting a big coil. Operating a ham radio station from an apartment in Maracaibo, Venezuela, the author demonstrates effective communication with over 100 countries using a custom-built indoor vertical antenna. Addressing common misconceptions, the design uses a balanced approach with radials and a base-loaded vertical element made from affordable materials. The antenna fits discreetly indoors, covers 6 to 40 meter bands, and achieves acceptable SWR with an MFJ tuner. Despite limited space and typical apartment challenges, the setup enables reliable DX contacts, confirmed by numerous QSL cards, proving indoor antennas can perform well in constrained environments.
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DXSpotter is a commercial Win32 HAM radio application for working with DX Clusters by using TCP/IP protocol for communications. It is adapted to satisfy most DXer's needs. DXSpotter includes 2 programs in one: DXSpotter for connections via telnet protocol to more than 200 DX Clusters, and DXSpotter-Summit for connections to OH2AQ's WEB cluster DXSummit page with automatic page refresh Price USD 25
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SolarHam is a website all about the Sun and how it affects Earth. This site is routinely updated with breaking news, sometimes hours before other Space News websites. You can trust SolarHam.com for the most up to date and accurate solar information on the net. SolarHam is a trusted and easy-to-use website for anyone interested in solar activity and space weather. It gives daily updates on <b>solar flares</b>, sunspots, geomagnetic storms, and radio blackouts. The site uses data from NOAA and NASA to show what is happening on the Sun and how it may affect radio signals on Earth. Charts and images are clear, and reports are updated often. Many amateur radio operators use SolarHam.net to check band conditions and aurora forecasts before operating. The site is fast, well organized, and focused on the needs of the radio community. Whether you are a beginner or an experienced ham, SolarHam.net is a helpful tool for understanding space weather and its impact on radio communications.
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Amateur radio dealer, scanners and accesories Burnaby, BC, Canada
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Yaesu Kenwood, drake MFJ JPS JRC AOR Daiwa Hygain Weltz Uniden Lowe Black Jaguar Trident dealer
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Mirko Pelcl's extensive radio collection features numerous historical transceivers and receivers, with a significant focus on military communications gear. The collection includes notable examples such as the Wireless Set No. 19, various Cold War-era military radios, and even a rare WWII spy radio utilizing a Loewe 3NF tube. Visitors can explore detailed sections dedicated to sets manufactured before 1945, including those used for military exchange, and a separate category for post-1945 radios, particularly those from the former Yugoslavia. The site also delves into specific modifications, like a digital head conversion for the RU-20, and showcases a frequency counter built with a microcontroller. This personal archive provides a unique glimpse into the evolution of radio technology, from early vacuum tube designs to more modern solid-state military transceivers like the PRC-515. The content reflects Mirko's dedication to preserving and documenting these pieces of radio history.
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Here are construction plans of a Turnstile antenna that can be used for space communication on the 2 meter amateur radio band. Specifically for 145.80 mHz
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Autotena, a Taiwanese manufacturer, offers a diverse product line focused on RF communication antennas and related accessories. The resource details various antenna types, including **4G/3G LTE wideband high-gain low-profile antennas**, land mobile wideband antennas, fiberglass omnidirectional designs, and GPS mobile and marine antennas. Specific amateur radio offerings include NMO VHF load coil gain antennas, VHF whip gain antennas with PL-259 connectors, and UHF NMO mount antennas with 3dB/5dB gain. The company also produces antennas for CB and 10-meter amateur bands, such as aluminum broadband 26-30MHz antennas and big copper coil broadband 26-30MHz antennas. Additionally, the site showcases **RF amplifiers** for CB, HF, VHF, and UHF bands, including professional-grade base station amplifiers with 100% EIA duty cycle. Handheld antennas, PL-259 type mobile antennas, magnet mount antennas, and external CB speakers are also presented, alongside various mounting kits and cable assemblies.
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MQ-1 four band HF beams 20,15,10,6 meters MQ-2 six band HF beams 20,17,15,12,10,6 meters, beam antennas and Hybrid Quad antennas
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PstRotator handles just about every controllable rotator in common use: Prosistel, Green Heron, HyGain, RC1 MDS, Rotor-EZ Idiom Press, Yaesu Az and many more PstRotator includes automatic tracking for satellite or EME communications, using programs like WSJT, VQLog, TACLog, Z-Track, GJTracker, EME System, Trak_SM, WXtrack, WinOrbit, Orbitron, Nova for Windows, Sat_Explorer, SatPC32, Win-Test. PstRotator supports remote control over TCP/IP.
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Broadband active loop antennas for radio amateurs and hobbyists
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Harger Lightning Protection is a full line supplier of lightning protection and grounding equipment, servicing the lightning protection, communications and electrical industries.
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Over 75 years of engineering expertise underpins Bird Electronic's offerings in RF power measurement, critical for maintaining peak performance in amateur radio stations and professional communication systems. The company specializes in a range of test equipment, including wattmeters, SWR meters, and antenna analyzers, essential for optimizing antenna systems and ensuring efficient power transfer. Their product line extends to various RF components such as filters, cables, and connectors, all designed to meet stringent technical specifications for reliability and accuracy across diverse frequency bands. Bird Electronic's instruments, like the _Bird 43_ Thruline Wattmeter, are widely recognized for their robust construction and precise measurement capabilities, providing hams with confidence in their station's operational parameters. These tools enable accurate assessment of forward and reflected power, SWR, and modulation characteristics, which are vital for troubleshooting and maximizing radiated power. The company's commitment to innovation ensures that its products remain relevant for modern RF challenges, from HF through microwave applications, supporting both traditional analog and advanced digital modes.
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Sells leading-edge voice and digital communications products to the world-wide military, government, industrial, and amateur radio marketplaces. Bluetooth Remote Audio/PTT, Rig Controller with Audio & PTT , HamLinkUSB Rig Control, Noise filtersm antenna analyzers, Multimode Data Controller, TNC, Packet Radio Terminal Node Controller. USB2RS232
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Presents the design and construction of an automatically tuned 7-30 MHz mobile HF vertical antenna, originally published in _QEX / Communication Quarterly_ in 2003. The resource details a base-loaded vertical antenna system that mounts on a vehicle's roof, incorporating a variable inductor as its loading coil. A three-legged chariot, driven by a modified model airplane servo, travels inside the coil to adjust inductance. The control unit, featuring a _Basic Stamp microcontroller_ and SWR sensor, emulates a Kenwood AT-50 tuner for seamless integration with a _Kenwood TS-50_ transceiver, allowing automatic tuning across all ham bands from 40 to 10 meters. The project emphasizes practical application, providing a solution to the narrow-banded nature of mobile HF antennas and the inconvenience of manual band changes. It achieves a maximum SWR of 1.3:1 across its operating range. The mechanical design is thoroughly documented with detailed drawings, including a full-resolution GIF and AutoCAD R14 DWG files, illustrating components like the stainless steel whip, PVC coil tube, and the servo-driven chariot mechanism. Construction requires a lathe, but the author notes it can be accomplished with a hobby lathe, making it accessible to those with moderate mechanical skills.
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The Packet Terminal Driver program is a general purpose communications package for communicating with a packet TNC attached to your IBM-PC/clone. The program was written to work with the Kantronics range of TNC's but should work with any TNC that is connected to a serial port on your computer.
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Point to Point hf ionospheric communications analysis and prediction program
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Experts in Wireless Communication, distributor of Ameritron, Bencher, Butternut, Hustler, Hy-Gain, MFJ, Microset, Mirage, PKW, Vectronics.
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The WN-1 is a precision RF Watt, SWR, and DC Meter to digitally monitor your amateur radio and emergency communications stations.
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This resource presents over 100 Q-signals, each with its corresponding question and answer format, as standardized by the International Telecommunication Union. The content delineates how these abbreviations can be expanded with additional groups, call signs, place names, or numerical data to provide specific context. It clarifies that a question mark following an abbreviation or its complementary information transforms it into a query. The document highlights that these operating signals, or Op Sigs, are prescribed for international use across all communication types, including military and non-military applications. It references their inclusion in Appendix 9 to the Radio Regulations Annex of the International Telecommunications Convention (Atlantic City) 1947 for QRA to QUZ blocks, and ICAO publications Dec 6100-COM/504/1 for QAA to QNZ blocks. The page specifically marks Q-signals of particular interest to amateur radio operators in red. The utility of Q-signals for concise communication in radiotelegraphy is evident, providing a structured method for conveying complex information efficiently. The resource serves as a practical reference for operators needing to quickly interpret or formulate messages using standardized codes, particularly beneficial for CW operation and international contacts.
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Manufacturer and direct seller of shortwave and ham radio antennas and accessories like TINYTENNA & YO-YO-TENNA