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Color photos, schematic and diagrams for an article written by N2APB for Fall 2000 QRPp. Also the subject of a presentation made at the Pacificon QRP Forum in October 2000.An Integrated and Portable PSK Station for 80 & 20 without using a PC!
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Lights on why 160 meters is so unpredictable and what is being done to reveal its secrets
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OSX/Mac and Windows versions of SdrDx. Supports RFSPACE, FunCube Pro, Andrus MK1.5, AFEDRI, FunCube Pro Plus, Peaberry, RTL sticks (RTL supported under OS X only, via this OS X RTL server) and Softrock SDR receivers.
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dxing.com explains utc time and gmt conversions to local time
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Falmouth amateur radio association of cape cod, massachusetts
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Two Delta-Loops in phase. The purpose of this article is to propose an antenna with a high gain, a high efficiency and a very low price that is easy to build for any frequency.
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Amateur television Repeater PI6ATS in the middle of the Netherlands. Output in 23 cm band, inputs in 13 cm and 6 cm band. All home made.
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Wiring Color Code and Pinouts for IC-706MkIIG and HM-103 Mic
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A 2 element small footprint 40 meter phased, reversible, downsized quad array antenna.
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A danish only scale diagrams designer, usefull to draw front panels and dial scale knobs, windows freeware.
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The Rock-Mite is a 40m CW kit offered by Small Wonder Labs . It features built-in keyer, direct conversion receiver with a crystal RF bandpass filter, 500 milliwatts of power, and switchable frequency offsets to work around QRM
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A large printable PDF file representing the world time zones. This map gives an overview of current local times around the world. If you ever asked yourself what time zone am i in, find your answer here.
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Yet another wiki page about the yaesu VX-2 hand-held transceiver.
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Istructions to use the IFD demodulator
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Interesting article on how build your own field day antenna
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How track and solve electrical interference from you computer
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The NL Ham Radio Swap Shop is an online platform dedicated to connecting amateur radio operators in Newfoundland and Labrador with opportunities to buy, sell, and trade radio equipment. This service caters to both seasoned operators and newcomers, providing a space for exchanging second-hand gear, military radios, antique radios, and radio tubes. Users can browse listings, post their own items, and find unique equipment that may not be available in traditional retail outlets. In addition to facilitating transactions, the Swap Shop also serves as a community hub for local hams. It encourages networking among operators, sharing of knowledge, and collaboration on projects. Whether you are looking for a rare piece of equipment or simply want to declutter your shack, the NL Ham Radio Swap Shop is an essential resource for anyone involved in the amateur radio hobby in the region.
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Understanding Amateur Radio NVIS Antennas and Propagation
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Freeware general purpose and contesting logging application, Scoring function for the IBM QSO Party with unique export format. Cabrillo export for non IBM contests includes formatting for NA QP, CQ WW DX, NA Sprint & CQ World-Wide WPX by W0RY
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Best audio settings, modifications and tricks for the Yaesu FT-2000 by DK3HV
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Calculating HF helical whip antenna for mobile or portable operation
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Radio Society of Tucson AZ web site
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Log2000 provides a structured environment for amateur radio operators to manage their contact records. This software facilitates the logging of two-way radio contacts, a fundamental aspect of the hobby, by capturing essential QSO data such as callsigns, dates, times, bands, and modes. It also supports the generation and printing of QSL cards and labels, streamlining the process of confirming contacts for awards and personal record-keeping. The program was specifically developed for Windows 95/98, Windows NT, and Windows 2000 operating systems. Its feature set includes tools for searching logs, generating various reports, and managing award progress. While tailored for earlier Windows versions, Log2000 offers core logging functionalities that remain relevant for basic station management.
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A site dedicated for the AM Radio Amateur and vintage radio. Home of the AM Press/Exchange, The AM Forum (the largest BBS of it's kind),and The AM Classifieds, Photos, Audio, and technical information. Audio and Video chat rooms.
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VE3CVG 222 MHz (1.25m) 6 element plumber's delight yagi antenna
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Sherwood Engineering Inc. (SEI) offers a repository of technical presentations and white papers focused on optimizing amateur radio transceiver and receiver performance. Content includes detailed analyses of _roofing filters_, transmitted IMD, and receiver characteristics, with specific discussions on products like the Drake R-4C and Icom IC-781. Presentations from events such as Dayton Contest University (2008-2014) cover topics like "How To Optimize Rig Performance," "Transceiver Performance: 10 Years of Change," and "Choosing a Transceiver: Far from Simple." Additional white papers address HF mobile antenna efficiency, ground screen alternatives to buried radial systems, and common receiver problems with solutions. The site also provides historical product information for items like the SE-3 MK IV synchronous AM detector and various 455 kHz mechanical and crystal filters, though many products are no longer in production. Receiver test data and alignment tips for the R-4C are also available, offering insights into rig modifications and performance enhancements.
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SCARA is active in various events throughout the year. Helping as a public service with communications at various events has been a strong point for our club
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The grounded half loop describe in this article is basically a half wave length wire on 80 Meters. The 80M grounded half loop antenna, inspired by a 1984 QST article by SM0AQW, is a compact solution for limited spaces. Comprising a 127-foot wire fed against ground and supported by radials, it balances performance and practicality. Despite compromises in length and proximity to structures, the antenna delivers strong signal reports and effective multi-band tuning using an SGC 237 antenna coupler. Ideal for CW operation, it offers low SWR on 80-10M, though noise levels and safety considerations warrant attention. This versatile design excels in constrained environments.
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An amateur radio contest log sheet printable in A4 format, useful for portable operations, free to download PDF File.
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Los Angeles County Disaster Communications Service a public service organization using Amateur Radio
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Guide to ground mounting antennas, notes on efficiency, elevated installations, metal towers and masts, other mounting schemas, moble homes and rv, lightning protections, artiche by Bencher
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Homebrew Light-weight Open-wire feedline for Portable Ops by N5ESE
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This calculator is designed to give resistor values for unbalanced T-pads, and for balanced H-pads.
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A homemade tunable bandpass filter for all HF bands from 160m to 10m
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Experiments with an 80 meter Inverted L Quarter wave antenna
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A collection of articles on the subject of impedance, impedance matching and high-frequency power transmission by G3YNH
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This page documents Amateur Radio data digipeated by the International Space Station
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This type of filter can be used in a Mode J satellite station (uplink on 2m, downlink on 70cm) to reduce the problem of the uplink signal desensing the receiver
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Here is a review of the 40 and 80 meter band Double Bazooka antennas as used on the HF shortwave bands.
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The Elecraft K2 transceiver requires specific modifications for optimal soundcard digital mode operation, particularly for PSK31. The original article, circa 2001, details initial challenges with manual PTT and speech compression settings. A key modification involves adding headphone audio and a compression disable signal to the K2's microphone jack, utilizing pins 4 and 5. The **COMP0** signal, active low, is shorted to ground via a non-inverting open collector switch circuit, comprising two resistors and two transistors, mounted on the SSB board near U3. This circuit provides effective control of an analog signal line with good noise immunity. The switchbox itself repurposes a computer COM port switch, using only two of its original connectors and four of the nine poles. It integrates a microphone preamplifier, a PTT circuit built with 'flying leads' construction, and RCA jacks for soundcard connections. A trimpot adjusts the audio drive to the K2. The central DB9 connector links to the K2's mic connector via a shielded RS232 serial cable, ensuring proper grounding and signal routing. An external footswitch PTT jack is also included. Further enhancements include a **noise-canceling microphone** preamp based on a QST December 2000 article, adapted for Heil mic elements. This preamp, built with pseudo-Manhattan style construction, provides a gain of approximately 2 by changing emitter resistors (R9 and R16) from 680 ohms to 330 ohms. A 10-ohm series resistor and 47 µF capacitor on the +5V supply mitigate noise spikes.
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Showcases the Del City Amateur Radio Club (W5DEL), an organization serving the amateur radio community in Del City, Oklahoma. The club facilitates local ham radio activities and provides a platform for members to connect. It emphasizes community engagement through various events and resources, supporting the interests of local operators. The club's online presence, while functional, appears to be a repurposed template, with some content not directly relevant to amateur radio. Members can access information on club dues, upcoming events, and community guidelines. The site mentions a focus on VoIP, suggesting an interest in **digital voice modes** and **internet-linked radio systems**. Although specific technical projects or operating achievements are not detailed, the club aims to foster camaraderie and provide a local point of contact for hams in the Del City area.
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Article on how use Genesys sowftware to design RF power amplifiers
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Ladder Line Myths, Line Types, Spacing and Impedance, Length by KV5R
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Electronic components dealer stocking RF adapters and many other popular items.
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The design and feeding of driven elements for VHF/UHF Yagi antennas , modeling, observations and some case studies by Graham Daubney F/G8MBI
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A fractional bandwidth of up to 30:1 characterizes spiral antennas, making them highly effective across a very wide frequency range, often from 1 GHz to 30 GHz. The resource details two primary types: the **Log-Periodic Spiral Antenna** and the **Archimedean Spiral Antenna**, defining each with specific polar functions and illustrating their planar configurations. It explains that spiral antennas are typically circularly polarized, with a Half-Power Beamwidth (HPBW) of approximately 70-90 degrees, and a peak radiation direction perpendicular to the spiral plane. The content elaborates on critical design parameters affecting radiation, including the total length (outer radius) for lowest frequency, the flare rate ('a' constant) for optimal radiation versus capacitive behavior, the feed structure (often an infinite balun) for high-frequency operation, and the number of turns (typically 1.5 to 3 turns). It also discusses the theoretical impedance of 188 Ohms for Log-Periodic spirals, derived from Babinet's Principle, noting actual impedances are often 100-150 Ohms. The article presents a simple construction method for an Archimedean spiral, demonstrating VSWR and efficiency measurements. Measurements from a constructed spiral antenna show a VSWR that is fairly constant across the band, albeit with a mismatch loss of about 3 dB. The antenna efficiency remains around -5 dB (31.6%) across its operating range, indicating a decent wideband radiator despite opportunities for optimization.
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A home made antenna tuner based on the W6JJZ basic concept that ,atches balanced loads without the use of lossy baluns, can provide band-pass filtering and harmonic attenuation.