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Design and manufacture antennas for mobile devices, wireless data including WiMAX, WiFi, and WISP (Wireless Internet), two-way radio and RFID (Radio Frequency Identification).

Microwaves101 provides an extensive repository of information covering fundamental principles of microwave design, targeting engineers and radio amateurs interested in the higher frequency spectrum. The site features a detailed _encyclopedia_ of microwave terms and concepts, alongside practical design considerations for various components and systems. It serves as a foundational reference for understanding RF propagation, transmission lines, and active/passive microwave circuits. The resource includes numerous calculators for impedance matching, filter design, and other critical RF parameters, facilitating hands-on project development. Discussions on **10 GHz** equipment and **24 GHz** projects highlight practical amateur radio applications, extending to operations up to 134 GHz. Content spans from basic theory to advanced topics like MMIC design and antenna characteristics, supporting both educational and practical endeavors in microwave technology.

The Covey Hill Amateur Radio Club operates a 146.685 MHz analog repeater with an 88.5 Hz PL tone, alongside several digital repeaters. The resource details specific frequencies and modes for D-STAR (145.590 MHz, 1266.300 MHz voice, 1297.675 MHz data on 23 cm), DMR-Marc (448.525 MHz), DMR-Brandmeister (441.750 MHz), Yaesu Fusion (449.725 MHz), and P-25 Digital (147.315 MHz). It also lists Echolink node 595040 (VE2REX-R) as an access point for the club's network. A recent update, dated June 19, 2024, announces the VE2REX analog repeater and Echolink are fully functional again, after resolving issues including a conflicting 100.0 Hz tone, software repairs for Allstar and Echolink, a suspected defective USB port on the Mini PC, and a faulty exciter in the Motorola Quantar repeater. Guy, VE2VMT, was instrumental in troubleshooting these problems. The club, established in 1994, provides a calendar, news, links, and membership information, with Linda Cullen, VE2NJK, serving as president and VA2DBJ as webmaster.

a subcommittee of the Amateur Radio Council of Arizona

On the field comparison among C-Pole antenna, an EFHW vertical antenna and an Inverter V dipole antenna. Test is done using two identical WSPRLite beacons that transmit with 200mW on the WSPR frequency and analyzing spotted results.

Time Mapper UHD is a versatile mapping and time visualization program offering multi-satellite viewing with frequency display and unique country-pairs for PskReporter data. It features live feeds from logging programs and can plot ADIF files. Ideal for schools, offices, or amateur radio stations, it provides customizable 4K or HD world clock displays with over 60 map layers, including ham radio zones and natural features. The program supports various time functions and can import logs for detailed analysis. It runs on Windows 10 or 11 and offers a 30-day free trial.

Upper New York Repeater Council, Inc, support the frequency coordination needs of the Amateur Radio repeaters operating in its area

Frequency coordinations on BC Canada

The Precision VXO (PVXO) and its matching Crystal Test Fixture (CTF) were created to provide a low cost means of evaluating the characteristics of crystals and a means of measuring their series resonant frequency.

Details Amphenol Connex's product range, focusing on RF connectors, adapters, and cable assemblies. The company produces common radio frequency interfaces such as _BNC_, _SMA_, and _TNC_ connectors, alongside numerous other specialized designs. These components are critical for establishing reliable signal paths in amateur radio stations, ensuring proper impedance matching and minimal signal loss across various frequency bands. The manufacturing process emphasizes precision engineering to meet the demanding specifications of RF applications, from HF to microwave frequencies. Product lines support diverse coaxial cable types, facilitating custom cable assembly for specific station configurations. The extensive catalog provides solutions for both fixed station installations and portable operations, addressing the needs of contesters, DXers, and general amateur radio operators.

The goal of this interesting project is to monitor a particular set of frequencies for a set period of time. In this article your will find instructions to build and operate an all-band WSPR node using cheap hardware and free software. At the end of this you'll have a Raspberry Pi, connected to an RTL-SDR dongle that monitors all of the WSPR frequencies rotating randomly every 15 minutes.

Sporadic E is a form of propagation that can arise with little warning, and enable radio frequencies of 150 MHz and more to travel over distances of a thousand kilometres and more.

The Straits Area Amateur Radio Club (SAARC) operates a 146.68 MHz (-) repeater with a PL tone of 110.9, serving Northern Michigan for emergency communications and community support. A temporary cross-band repeater on 445.875 MHz is also available during specific hours, enhancing local coverage. The club actively supports disaster services through its repeater infrastructure and coordinates local community events. SAARC provides resources for prospective hams, including information on licensing classes and testing sessions, and promotes amateur radio education. Members and interested individuals can join the club's Groups.IO group for updates and participate in the Bill DeMay _K8GUG_ Memorial Net, held weekly on Monday evenings at 8:00 PM on the primary repeater frequency.

recognized Amateur Radio Frequency Coordinating entity for the State of Arkansas.

Crossband Repeating is a process where a Ham transmits one signal on one band (typically UHF), and it is received by another radio with a better antenna/power installation, and re-transmitted (typically on VHF) to another radio system, or a repeater. Everyday examples of cross-band repeaters are repeater receive sites that hear the input signals on 2m and retransmit those signals on a frequency higher than 220 MHz.

List of global weather fax (HF fax) stations, including their locations, call signs, and frequencies. Click on any station's call sign to view its weatherfax broadcast schedule. This site provides various radiofax receiver manuals in PDF format, on the Receivers page.

NanoVNA based on edy555, use the odd harmonic extension of si5351 to support the measurement frequency up to 900MHz. GitHub repository.

There are several ways to reduce the length of a dipole and still use it as an effective antenna. Remember it is the electrical length that determines resonance. The physical length can be considerably less than a half wave length on your desired frequency as determined by 468/f MHz.

Choking balun for lower HF and MF bands. (1.8MHz - 10MHz). Requiring a choking balun to isolate the potential RF pick up on the coax cable as it runs past equipment such as computer within the radio room at lower HF and MF frequencies a simple method of winding RG58 coax onto a Powdered Iron Toroid Core was constructed.

Article about Standing-wave ratio (SWR) defined as a mathematical expression of the non-uniformity of an electromagnetic field on a transmission line. SWR is the ratio of the maximum radio-frequency (RF) voltage to the minimum RF voltage along the line.

Illustrates the fundamental principles of radio repeaters, detailing their role in extending communication range beyond line-of-sight limitations. It begins by defining _simplex communication_ as a direct radio-to-radio link, effective only when no obstructions impede the signal path. The resource then introduces the concept of a repeater (or base station) strategically positioned on elevated terrain, such as a mountain, to overcome geographical barriers. The article clarifies the repeater's operational mechanism: it receives a signal on one frequency and simultaneously re-transmits it on a different frequency, enabling users on opposite sides of an obstruction to communicate. This _duplex operation_ is likened to satellite communication for VHF propagation, but with a fixed terrestrial station. Specific examples of signal paths are provided, showing how a handheld radio transmits up to the repeater, which then relays the message down to another user, effectively bypassing obstacles like hills or large buildings.

A Western Pennsylvania Radio Guide

Presents Wayne Kerr Electronics, a manufacturer specializing in precision component measurement products. The company offers a range of LCR meters, impedance analyzers, and transformer test systems designed for various applications in electronics manufacturing and research. Specific product lines include the 3260B Precision Magnetics Analyzer, which measures inductance, capacitance, and resistance with high accuracy, and the 6500B series of LCR meters, capable of testing components across a broad frequency range up to 120 MHz. The 3255B and 3265B series provide solutions for transformer and inductor testing, including turns ratio, leakage inductance, and inter-winding capacitance measurements. These instruments are utilized in quality control, component characterization, and production line testing, ensuring performance and reliability in electronic circuits. Wayne Kerr's offerings support engineers and technicians in verifying component specifications.

The MiniTioune receiver project, developed by Jean-Pierre F6DZP, consists of the home constructed MiniTiouner hardware which interfaces via a standard USB 2.0 port to a Windows PC running the MiniTioune software. It can be used to receive satellite broadcasts transmissions making it ideal for use on Q-oscar 100 Es hail-2 without any external frequency converters.

This page provides a list of UK scanner frequencies, specifically focusing on the Police UHF bands. It is a useful resource for hams interested in monitoring and listening to police communications in the UK. The page offers a detailed breakdown of frequencies used by the police, allowing hams to stay informed and connected to emergency services in their area.

The Waterway Net, sponsored by the Waterway Radio and Cruising Club, is dedicated to enhancing amateur radio communications for recreational boaters. Meeting daily at 0745 ET on 7.268 MHz LSB, the net focuses on safety and weather updates, providing a vital link for live-aboards and cruising boats to stay connected with families and friends. Position Reports and Float Plans are essential components that ensure safety for offshore passage makers. Established in the early sixties, the Waterway Net is one of the longest-running nets in amateur radio history. Open to all amateur radio operators with a General class license or higher, it encourages participation without requiring WRCC membership. Newcomers are advised to listen initially to understand net procedures before checking in. In emergencies, FCC regulations allow anyone, licensed or not, to use any frequency to call for help, with the 20-meter frequency of 14.300 MHz available for emergency assistance approximately eighteen hours a day.

TelExpress provides a wide array of RF and data connectivity products, including various coaxial cables like LMR-series equivalents, fiber optic cables, and Ethernet solutions. Their inventory supports diverse amateur radio and telecommunications requirements, from antenna feedlines to network infrastructure. The site emphasizes bulk cable availability and custom assembly services, catering to both individual hams and larger installations. Key offerings include _low-loss coax_ for HF and VHF/UHF applications, along with a comprehensive selection of RF connectors. They also supply patch panels, Ethernet cables (Cat5e/Cat6), and general wireless and telecom hardware. Customers can find components for building robust station infrastructure, ensuring signal integrity across various frequency bands. The platform facilitates procurement of essential parts for new builds or upgrades, supporting reliable RF system performance.

Discover the key facts about what radio propagation is, the different types available and how they affect different frequencies.

Passive Bandpass Filter online calculator and filter formulas. Active Inverting Op Amp Bandpass Filters, Active Noninverting Op Amp Bandpass Filter, just enter the Low ir High Cutoff Frequency

A document that includes a list of all countries implementing CEPT licence, with detailed information on licence types like standard CEPT, CEPT Novice and HAREC. A full list of frequencies, and call signs schemas to be used by foreign operators, compiled by Hans Schwarz, DK5JI

This article describes a simple yet effective multi-band vertical HF antenna design that performs exceptionally well across 80m to 10m bands. The antenna consists of a 13.4m wire mounted on a 12.4m Spiderpole, complemented by four 12m radials and a ground rod. Initially tuned with a manual LC circuit, it was later upgraded with a CG3000 remote auto ATU for convenient band switching. Despite antenna modeling software suggesting limited performance on higher frequencies, the system demonstrated excellent DX capabilities across all bands, outperforming more complex vertical antenna designs.

A spectrum analyzer is always an usefull amateur radio test equipment that should be present in a radio shack. Hams can use it for testing frequency response of filters, amplifiers, and other two-port RF devices. This article illustrate a tracking generator compatible with any spectrum analyzer in the Tektronix 490- and 2750-series lineups

Wisconsin UHF VHF scanning frequencies

Online HF Communication prediction system provided by the Australian Governament Buerau of Metereology allow to predict usable frequency rage for radiocommunications between two stations allowing to specify frequency and date range. This tool allow calculation with different methods and algorithms

The amateur radio listener for when you're not on the radio. Repeater-START, the offline repeater listing app for Windows, Linux, Raspberry Pi, Ubuntu, Librem Phone is available, Now with grid square display, topographical maps and frequency preferences

This transmitter covers the 160, 80, 40 and 20 metre bands and provides both SSB and properly generated CW. The CW side of this transmitter is not compromised and produces excellent CW. On SSB the audio has been tailored to provide a rising response to 3 KHz, with a sharp drop above that frequency. There is RF speech clipping to both provide more "punch" and to limit the peak output.

The PCB can produce a High Frequency RF signal in the range of 1MHz to 12.5MHz using an AD9833 Direct Digital Sequence (DDS) frequency synthesizer. The signal can be modulated with different Weak Signal modes such as WSPR, JT9 and JT65 using our Arduino 5V/16MHz Pro Micro software.

This article shares the author's experience with building antennas. After putting a large magnetic loop project on hold, they decided to try a base-loaded vertical antenna. The author explains how they chose to design a new antenna from scratch, aiming for a frequency of 7 MHz. They describe the calculations needed to find the right coil inductance and how they used 3D-printed parts for the construction. The article wraps up with results from their initial tests, showing good communication on different bands and highlighting the success of their design.

open source hardware for software-defined radio. HackRF One is an open source hardware platform that can be used as a USB peripheral or programmed for stand-alone operation. 1 MHz to 6 GHz operating frequency

All Satellites Frequency List Update. A complete list of satellite frequencies available in several formats, including info on Satellite Uplink and Downlink frequencies Beacon, operative Mode, Callsign and Weather sat functionality.

The video delves into the significance of interference reduction in ham radio setups by utilizing ferrite materials. It demonstrates the use of spectrum analyzers and tracking generators to showcase the performance of ferrite devices in minimizing noise levels. The analysis includes insights on resistance levels, attenuation factors, and the impact of using multiple ferrite clamps or rings to enhance noise reduction capabilities. Viewers gain a deeper understanding of ferrite composition, characteristic curves, and winding techniques for effective noise attenuation in different frequency ranges. Overall, the video serves as a comprehensive guide to optimizing interference reduction in radio environments through the strategic use of ferrite materials.

Operating an amateur radio station effectively requires reliable coaxial cable to minimize signal loss between the transceiver and antenna. SIVA Cavi, an Italian manufacturer, produces a range of coaxial cables, including specific 50 Ohm low-loss types suitable for amateur radio applications. Their product line features cables like **RG 58 SHF1**, **RG 213 SHF1**, and **RF 400 SHF1**, which are commonly deployed in HF and VHF/UHF setups. The company also offers specialized cables such as the **HF 214 UF Ultraflex**, a high-performance broadband low-loss 50 Ohm cable designed for flexibility and reduced attenuation across various amateur bands. These cables are engineered with solid or foam dielectric materials, impacting their electrical characteristics and suitability for different power levels and frequency ranges. For instance, foam dielectric cables often exhibit lower loss at higher frequencies, a critical factor for VHF/UHF operations. Beyond amateur radio, SIVA Cavi manufactures cables for digital video broadcast, offshore marine use, and fire detecting systems, demonstrating a broad engineering capability in coaxial cable technology.

This page provides detailed information on various antenna designs specifically tailored for hams operating on the 80m and 160m bands. The article covers the pourpose and usefulness of each design, helping hams optimize their radio communication capabilities on these popular bands. Whether you are a beginner looking to improve your setup or an experienced operator seeking new ideas, this page offers valuable insights to enhance your ham radio experience on the 80m and 160m frequencies.

Just a simple signal generator based on ADF4351 module from fleebay allows you to generate one single frequency that can go up or down in 100Khz steps via two push buttons.

Conventional scanner frequencies for the San Francisco Bay Area, now in a fully searchable database

The video showcases the setup of a 300 MHz oscillator, a 100W radiofrequency amplifier, and a dipole antenna for transmitting radio waves, leading to the fluorescence of a nearby light bulb. It demonstrates the presence of standing waves on the dipole antenna and how intensity varies along its length. Additionally, the usage of a copper pipe as a receiving antenna is explored, showing changes in intensity depending on alignment and proximity to the transmitter. Finally, a B field antenna sensitive to magnetic fields is introduced, revealing brightness variations in different orientations. The video offers insightful observations on radio wave transmission and reception phenomena.

Explains the fundamental purpose of a repeater, detailing how these automated relay stations overcome distance and terrain limitations for VHF/UHF communications. It traces the historical development from early Bell Telephone Labs "relay" stations in 1922 to Art Gentry, W6MEP's, pioneering K6MYK amateur radio repeater in the mid-1950s, which remains active today. The resource clarifies the distinction between simplex and duplex operation, including the unique function of a "parrot repeater" for single-frequency recording and playback. Delving into the internal workings, the guide breaks down a repeater into its core components: the antenna system, feedline (often _Heliax_ or hardline for minimal loss), duplexer, receiver, transmitter, and controller. It emphasizes the critical role of the duplexer in preventing receiver desensitization by isolating transmit and receive signals, even with distinct frequencies. The discussion highlights the importance of high-performance, durable antennas and low-loss feedlines, citing examples of equipment installed in the 1960s and 1970s that are still in perfect working order. Operating a repeater is also covered, with an explanation of frequency offset (e.g., the 600 kHz standard for 2 meters) and the function of _CTCSS_ (PL tone) for access. It outlines standard input/output offsets for various bands, from 6 meters to 23 centimeters, while noting regional variations. The guide also touches on features like autopatch and Digital Voice Recorders (DVRs), providing a solid foundation for understanding repeater technology and usage.

This page provides a fully customizable band plan. You can easily customize the frequency limits, scale, define custom windows for modes and activities, adding or removing bands. You can tehn Export to PDF or print the bandplan to distribute the document to help hams operating within the designated spectrum efficiently. Useful for both new and experienced hams looking to produce their custom bandplan.

These frequencies have been adopted into the bandplans of each IARU region to be a focus for emergency communications in their areas. They are not absolute frequencies but instead are centres of activity and emergency communications may be found around 20kHz from these centres. Some countries may maintain other emergency frequencies in their own bandplans due to local requirements, QRM etc

This page presents an online calculator tool for determining the dimensions of various HF wire antennas operating between 1.8-30 MHz. Users input their desired resonant frequency to obtain precise measurements for four popular antenna types: standard flat-top dipole, inverted Vee, quad loop, and equilateral delta loop. The calculator provides comprehensive measurements including leg lengths, minimum heights, horizontal spreads, and feedpoint distances. Accompanying the calculator are detailed technical explanations, construction notes, and installation guidelines for each antenna type, making it a practical resource for amateur radio operators building their own antennas.