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How is your SWR - determine the power loss to expect for a given SWR, includes an excel spreadsheet by n3ujj

The correct procedure for measuring SSB PEP (Peak Envelope Power), using an oscilloscope with a vertical bandwidth of at least 20 MHz, or a monitor scope.

Electric Fields, magnetic fields, electromagnetic fields, losses, fresnel zone, nearfield and farfield

The N1HFX thermal cooling fan controller project details a practical circuit designed to manage cooling fan operation based on temperature, a common requirement for high-power amateur radio equipment. This build utilizes a **LM34** temperature sensor, providing a linear voltage output directly proportional to Fahrenheit degrees, simplifying the control logic. The circuit's core functionality involves a comparator that activates the fan when a preset temperature threshold is exceeded, ensuring efficient cooling and reducing unnecessary fan noise. This controller is particularly useful for amplifiers, power supplies, or transceivers that generate significant heat during operation. The design incorporates a _TIP120 Darlington transistor_ to drive the fan, capable of handling up to 5 amps, making it suitable for a range of fan sizes and current requirements. Field results indicate stable temperature regulation, preventing thermal runaway in enclosed environments. Construction involves readily available components, making it an accessible project for hams looking to optimize their station's thermal management.

KComm, a logging and communication program, was specifically engineered for Elecraft K2, K3, and KX3 transceivers, leveraging the Lazarus cross-platform development tool. It operates natively on Windows XP and can be compiled for Linux, with potential for macOS, prioritizing low resource usage for casual DXers and contest participants. The software integrates with external applications like Fldigi for diverse digital modes and CW Skimmer for advanced Morse decoding, enhancing its functionality beyond basic logging. The design philosophy of KComm emphasizes utilizing the physical radio controls for operational adjustments, rather than replacing the transceiver's front panel. It facilitates keyboard CW operation via the Elecraft serial protocol and capitalizes on the K3 and KX3's built-in decoders for RTTY and PSK31. Additionally, KComm supports PSK31, PSK63, and PSK125 through the AE4JY PSK Core DLL on Windows and integrates with PSKReporter.info for spotting. While not a dedicated contest logging or award tracking program, KComm supports ADIF and Cabrillo export for casual use, allowing logs to be imported into other software. The author, G4ILO, ceased all software development, providing KComm "as is" without further support or updates; however, the source code is available under the GNU GPL for community continuation.

Article on antenna feed impedance and the importance of matching RF andtennas to feeders, including notes on Radiation resistance, loss resistance, and efficiency are also detailed.

Constructing a high-performance RF spectrum analyzer up to 1000 MHz requires careful attention to component selection, shielding, and circuit isolation. This resource details a project that improves upon the _Spectrum Analyzer for the Radio Amateur_ design by Wes Hayward (W7ZOI) and Terry White (K7TAU), incorporating ideas from Scotty Sprowls' project, particularly his 1013.3 MHz IF bandpass cavity filter. The analyzer utilizes a Mini-Circuits SRA-11 mixer with a sweeping local oscillator from 1013 to 2013 MHz, feeding into a 4-pole copper pipe cavity filter. The design employs a second SRA-11 mixer with a fixed 1024 MHz LO to produce a 10.7 MHz final IF. This signal then passes through narrowband resolution filters and is processed by Analog Devices AD603 and AD8307 ICs for IF amplification and logarithmic detection, driving an oscilloscope in X/Y mode. The project emphasizes modular construction, using salvaged components and double-sided FR4 material for PCBs, with critical notes on minimizing spurious images through effective shielding and proper voltage regulation for each module. Key components include a Z-Communications V585ME48 VCO for the first LO and a Z-Comm V583ME01 VCO controlled by a Motorola MC145151 PLL for the second LO. An optional Hittite HMC307 step attenuator and K&L 5L121-1000/T5000-O/O low-pass filter manage RF input. Tuning procedures for the 10.7 MHz IF resolution filter are also detailed, showing before-and-after spectrum views.

Decode DTMF from your iPhone. Hold your smartphone close to a DTMF source and this app will decode the numbers being dialled.

A 12v portable oscilloscope project

An antenna system is electrically small if it's enclosing sphere is <&#955;/2&#960;. So a 10m band antenna of under 1.6m long qualifies.

Maintaining vintage Eddystone receivers often presents unique challenges, as detailed by Victor Jenkins in his refurbishment of an EA12, where his deep understanding of RF circuits ensures optimal performance for daily shortwave listening. Similarly, Gerry O’Hara VE7GUH, a prolific contributor to the EUG website and a trustee, meticulously documented his restoration of an Eddystone S830/2, even addressing an unusual instability issue with a follow-up postscript article and YouTube videos demonstrating the fix. His work, along with numerous other articles on the "Restorations" page, showcases a master's approach to bringing vintage sets back to factory specifications or better. Beyond technical restorations, the EUG also shares compelling historical narratives. One such story recounts the discovery of a long-lost 78rpm recording featuring Eddystone Radio Ltd.'s founder, George Stratton Laughton, and other key figures discussing the company's wartime and post-war contributions to shortwave communications. This six-minute BBC production, transcribed into an MP3 file by Peter Carney, offers a rare auditory glimpse into the company's legacy, highlighting its role in supplying equipment to police, ministries, and expatriate British workers. The community aspect thrives through shared experiences, like Roger Trickett's anecdote about his Eddystone EC10, which has been continuously powered for 50 of its 54 years, traveling across continents and enduring various modifications. Another intriguing account from Roy GM4VKI details the "S640 Identity Crisis," where a seemingly standard S640 receiver turned out to be a masterfully engineered 80/20-meter SSB transceiver built into the original chassis by GI3ZX, showcasing incredible ingenuity from a bygone era of amateur radio.

Tel-atomic sells physics educational apparatus, oscilloscopes, counters, magnetic meters

The simple and convenient way to a custom front panel - even for single units. Custom-designed front panels and enclosures for electronic equipment.

The _Nemos Photography_ blog presents a curated visual gallery focusing on _Morse keys_, offering a detailed photographic exploration of various telegraphy instruments. Each entry typically features high-resolution images of specific keys, highlighting their design, construction, and historical context. The content serves as a visual reference for collectors and enthusiasts interested in the aesthetics and mechanics of CW sending devices, often including close-ups of key components and unique features. This resource allows for comparative study of different key types, from vintage straight keys to modern paddles, without delving into technical specifications or operational performance. The emphasis is purely on the visual documentation of these artifacts, providing a unique perspective on the evolution and diversity of Morse key designs. It is a specialized collection for those who appreciate the craftsmanship and historical significance of telegraphy hardware.

Use your Smartphone as an Oscilloscope to visialize signals from 150 Hz to 15kHz and as a Signal Generator to generate sinusoidal, square and triangular signals up to 15kHz

Demonstrates the construction of a high-power 6-meter (50 MHz) amplifier, specifically designed for demanding modes like EME, TEP, and multiskip Es. It details the use of a _GU-43B_ tetrode in a grounded-cathode configuration, emphasizing the need for stabilized grid voltage and input capacitance compensation. The resource provides a comprehensive schematic, power supply design, and practical considerations for component sourcing, particularly for high-voltage and high-current sections. The builder achieved an output power of **1250 watts** with an anode current of 0.65 amperes and 3200 volts anode voltage. The article also covers the physical construction within a modified P6-31 enclosure, outlining the internal layout for RF and power supply sections, and includes photos of the completed unit. It highlights critical safety precautions for working with high voltages and reactive currents up to **20 Amperes** in the P-network.

Details Amphenol's extensive product line, encompassing electrical, electronic, and fiber optic connectors, alongside coaxial and flat-ribbon cable solutions. The company designs, manufactures, and markets these interconnect systems globally, serving various communication network requirements. Their offerings support end-to-end connectivity, crucial for modern broadband infrastructure. Emphasizes the company's role as a major provider of components vital for reliable signal transmission in diverse applications. Products like _LMR(R) coaxial cables_ and various _RF connectors_ are essential for amateur radio installations, ensuring low loss and robust connections for antennas and transceivers. The focus on high-performance interconnects directly benefits hams constructing or upgrading their stations. Amphenol's broad portfolio includes specialized connectors and cable assemblies, meeting rigorous technical specifications for both commercial and amateur radio use.

A folded dipole is an antenna, with two conductors connected on both sides, and folded to form a cylindrical closed shape, to which feed is given at the center.

This project takes after the VGA-to-Scope converter by using composite video rather than VGA signals to create a display on an oscilloscope.

Sort of similar to the one of the 6m omni. Instead of using twin-lead, this design makes use of a more or less regular double bazooka antenna (coaxial dipole). Your attention shall be drawn to the available standart literature, such as Rothammel. In order to "compute" the dimension, Karl Rothammel mentioned that the total length of the dipole shall be 95% of the free-space wavelength. The short-circuit bridges (closing the folded dipole) are to be placed at a distance-fraction being equal to the velocity factor of the coax cable used, which will be 66% using RG-58 or RG174.

Focused on technology to serve emergency response in clackamas county, oregon.

Amateur Radio Full Disclosure

Operating a modern amateur radio station, particularly for advanced digital modes or microwave experiments, often requires precise test and measurement equipment. This resource from NI (National Instruments), now part of Emerson, showcases a wide array of hardware and software solutions designed for demanding test objectives. Their portfolio includes modular instruments and configurable software interfaces, such as _LabVIEW_ and _TestStand_, which integrate AI assistance via _NI Nigel™ AI_ for code completion and sequence building. For those involved in RF and microwave work, the offerings extend to vector signal transceivers, RF signal generators, software-defined radios, and spectrum analyzers. These tools are crucial for characterizing antenna performance, optimizing transceiver circuits, or developing custom radio systems. The company emphasizes its 50 years of innovation, with 40 years dedicated to _LabVIEW_, highlighting a long-standing commitment to engineering solutions. The site also details products for data acquisition, electronic test, and wireless design, covering components like CompactDAQ modules for precise sensor measurements and various communication bus interfaces. Their events and perspectives sections offer insights into topics such as 5G technology and strategies for breaking out of testing silos, providing a broader context for their measurement solutions.

Besides protection from lightning, this ARRL "All Risk" Ham Radio Equipment Insurance Plan also gives you the protection you need from loss or damage to your amateur station

MikroTik is a Latvian company which founded in 1995 to develop routers and wireless ISP systems. Wifi Routers, router boards, switches, interfaces and enclosures.

A technical article that want to explain Coaxial Cable terms, specifications and applications. A glossary of technical terms with clear explanations.

Located in Southwest Michigan, in Berrien County

Coaxial cable stripping for PL-259 connectors requires precise measurements to ensure optimal RF performance and mechanical integrity. For RG-8X, the outer jacket is stripped 1/2 inch, the braid 5/16 inch, and the dielectric 1/8 inch, leaving the center conductor exposed. RG-58 preparation involves a 1/2 inch jacket strip, 1/4 inch braid strip, and 1/8 inch dielectric strip. These specific dimensions facilitate proper soldering and crimping, minimizing impedance discontinuities at the connector interface. Different coaxial cable types, such as RG-8 and RG-213, necessitate varied stripping lengths due to their construction. The _PL-259_ connector, a common UHF type, relies on these exact preparations for a secure fit and low-loss connection. Incorrect stripping can lead to high SWR, RF leakage, and mechanical failure, impacting overall station efficiency. The guide details these critical dimensions for several popular coax cables. Using a dedicated _coax stripper_ tool or precise measurements with a utility knife improves consistency.

This article is about two excellent small helical antennas for the two meters band. With performance close to that of full sized antennas, these small helical antennas are low in profile but high in efficiency.

Article that try to answer to questions that arises about losses in the ladderline, and how they change when the line is wet by g3txq

Converting a computer\'s VGA output for an oscilloscope

This Return Loss Bridge has been designed to characterize the input impedance of a receive strip, and the output impedance of a transmit strip

Easiest possible tuning steps using a closed CW key, FM or AM tuning the Ameritron AL-811H

New, used, & reconditioned electronic test & measurement equipment sales, rentals, & service. Agilent/HP Spectrum Analyzers, Tektronix Oscilloscopes, Fluke Calibrators, & much more.

I am an EMT-B,an Incident Commander for NM Search and Rescue and an Amateur Radio Operator - KD5KTY Dedicated to the Preservation of Life through Search, Rescue and Education services.

Operating an amateur radio club, VE2CEV details its activities, including regular meetings and a significant project involving the construction of a **satellite ground station**. The resource outlines the project's inception, team formation, equipment acquisition, and the physical installation of antennas and rotator systems. It specifically mentions the use of a dual-axis AZ/EL rotator and antennas for VHF, UHF, and SHF (2 meters, 70 centimeters, and 13 centimeters), along with the strategic use of **Heliax cables** to minimize RF signal loss. The club also provides information on its interconnected repeater network covering southwestern Montérégie. The content highlights the practical application of the satellite station for communicating via amateur satellites and the International Space Station (ISS). It details the collaborative effort of members in securing a powerful Linux server, negotiating antenna installation with local authorities, and the precise alignment of antennas. The club emphasizes its role in guiding new amateurs, offering demonstrations, and potentially organizing courses, indicating a focus on community engagement and technical education within the amateur radio hobby.

A close up of Doppler Shift, a phenomenon which is commonly observed by the lay person, yet still confuses many amateur satellite operators.

The Metropolitan Amateur Repeater System's KJ6TQ repeater serves Los Angeles Area ham radio operators on 447.820 MHz

Tektronix Oscilloscope Tutorial Learning Center, includes tutorials for understanding oscilloscope basics and operation.

TIM-CO, an authorized distributor, offers a range of electronic components crucial for various applications, including amateur radio station builds. Their inventory focuses on **connectors**, both commercial and military-grade, which are essential for robust and reliable interconnections in radio equipment and antenna systems. This includes a variety of types suitable for RF applications, ensuring signal integrity. Beyond connectors, TIM-CO provides passive and electromechanical components, fundamental building blocks for any radio circuit or control system. These components are vital for constructing filters, impedance matching networks, and power distribution systems within a shack. Their selection supports both new construction and repair of existing gear. Additionally, the company supplies **RF-coax cable assemblies**, pre-fabricated solutions that save time and ensure proper termination for feedlines and inter-component connections. These assemblies are critical for minimizing signal loss and maintaining impedance matching from the transceiver to the antenna.

Ham radio club in west Los Angeles

The TECLA Thirty, an early wireless age crystal set, is featured among a gallery of over 100 collectible headphones, with detailed close-up photos of vintage models. Several pages offer vintage headphones for sale, including Brandes, Baldwin, and Western Electric, suitable for crystal set use or collecting. Construction details are provided for a reproduction KILBOURNE AND CLARKE crystal set, built with vintage 1920s parts and featuring a miniature variable condenser for fine tuning. The resource also presents a project for a simple crystal radio and a 1-tube amplifier, complete with a schematic and component diagram, suitable for driving a horn speaker or amplifying weak signals for headphones. Instructions for mounting argentiferous galena detector crystals are included, along with information on MRL Handbooks covering crystal detectors and modern diodes. Additional projects include a 2A3 single-ended triode tube amplifier and two stereo tube amps using 12AX7, 6V6, 5Y3G, 6SN7, VT-25, and 5U4G tubes.

This resistor calculation tool shows which combinations of two resistors, series or parallel, gives a match better than the closest standard value.

Efficient Low Band Counterpoise for Restricted Circumstances Loss Avoidance Opportunities and Techniques for the Low Bands The short and linear FCP was designed to reduce ground losses from inadequate radial systems beneath inverted L and other vertical antennas.

A deep analysis of UHF connectors performance tests, including return Loss of UHF Connectors, Mismatch Loss of UHF Connectors, SWR of UHF Connectors

RF Feedline (Coax and Ladder-Line) Loss and ERP Calculators made with Javascript. This complex feddline loss calculator has already several line types paramenters for most common coaxial cables from Belden, Time LMR, Wireman and other common products. Result will give Matches loss, SWR loss, dB and Watts power loss.

Offers a range of high-performance RF interconnect solutions, addressing the critical need for reliable signal integrity across diverse radio frequency applications. Their product line includes custom cable assemblies, various **RF connectors** (such as SMA), adapters, and terminators, designed to meet stringent specifications from DC up to 40 GHz. These components are essential for maintaining low insertion loss and excellent VSWR in demanding environments, from test benches to operational communication systems. The company specializes in providing tailored solutions for both commercial and government sectors, emphasizing precision manufacturing in Warner Robins, Georgia. Their offerings are crucial for engineers and operators requiring specific lengths, connector types, and performance characteristics for their radio equipment and test setups. Ensuring robust connections and protection against transient voltage events, their **surge protectors** are integrated into systems to safeguard sensitive electronics from damage, a common concern in outdoor or high-power installations.

High Speed Multimedia (HSMM) radio, as introduced by John Champa, K8OCL, represents a significant advancement in amateur radio's digital capabilities, moving beyond traditional keyboard modes like packet radio. This initiative, driven by ARRL's Technology Task Force, focuses on developing high-speed digital radio networks capable of up to 20 megabits per second. HSMM primarily facilitates digital voice (DV) and digital video (ADV), enabling real-time video transmission from emergency scenes to an EOC without expensive ATV gear, often requiring only a laptop, a PCMCIA card, a digital camera, and a small antenna. The working group's initial efforts concentrate on cultivating microwave skills within the amateur community to build and support portable and fixed high-speed radio-based local networking, or **RLANs**. These networks prove invaluable for RACES and ARES organizations, as well as homeland security and other emergency communications. Field Day exercises and simulated emergency tests (SETs) are encouraged to hone skills in rapid site surveys and deploying broadband HSMM microwave radio networks, with examples like linking Field Day logging stations or antenna test results at the Midwest VHF-UHF Society Picnic 2003. Getting started with HSMM often involves adapting off-the-shelf **IEEE 802.11** (WiFi) equipment to comply with amateur radio regulations, typically operating in the 2.4 GHz ISM bands. While consumer WiFi gear has range limitations under Part 15 rules, proper setup under amateur regulations can extend coverage significantly, with test networks like the Hinternet achieving 5-15 mile ranges at 54 M bit/s using small mast-mounted dish antennas. Careful selection of equipment with external antenna ports, high transmit power, and low receive sensitivity is crucial, along with using low-loss coaxial cable like LMR-400 for optimal performance at these frequencies.

A simple reading that allows to understand the basic working concepts and uses of an oscilloscope

Voldatech, a manufacturer based in China, produces a range of RF feeder cables and site components essential for amateur radio installations and telecommunication infrastructure. Their product line includes various types of coaxial cables, such as **50 Ohm** and 75 Ohm options, along with a comprehensive selection of connectors like N-type, UHF, and BNC. These components are critical for maintaining signal integrity and minimizing loss in antenna systems, whether for a home shack or a remote DXpedition setup. The company's focus on _RF Coax cables_ and connectors directly supports the needs of radio amateurs seeking reliable transmission lines for their transceivers and antennas. Amateurs often compare Voldatech's offerings to established brands, evaluating factors such as impedance matching, shielding effectiveness, and durability under various environmental conditions. The availability of diverse cable types allows operators to select optimal solutions for different frequency bands and power levels, from QRP to high-power amplifier setups. Their products are particularly relevant for those constructing new antenna arrays or upgrading existing feedline systems, aiming to achieve maximum power transfer and reduce standing wave ratio (SWR) for efficient signal propagation.