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Remote viewing can be useful for Hams, in example remotely viewing antennas during a storm.

A simple 3D Paddel CW Key made of plastic with a standard 3d printer

Web site dedicated to articles relating to Ham and CB Radios and antennas, reviews and classifieds.

Here is a formula and calculator for creating a loaded (shortened) quarter wave vertical or balanced dipole. The calculation refers to either a loaded 1/4 wave or a loaded dipole

Personal page of the Dutch Amateur Radio Station PA1CW

An original amateur radio blog in Esperanto lenguage, all about ham radio, DX, antenna.

Vanuatu YJ0X, DX pedition 3-14 October 2014

In this article we share a useful and simple project to convert an unneeded car power cable to an Anderson PowerPole adapter.

The program serves to assist in a ham-radio activities secretarial with his hobby , such as Printing QSL cards or print labels directly from the program , printing envelopes and mailing envelopes for the feedback you send direct QSL cards, download address for sending cards direct from QRZ.COM or for any station. Checking whether for the QSO and his country is present QSL bureau.

NearSys (Near Space Systems) is a multifaceted organization, with interests in near space exploration, microcontrollers, robotics, space, and astronomy. Includes a section dedicsated to Amateur Radio High Altitude Ballooning

A simple and cheap solution to monitor temperature of your repeater implementing a Raspberry Pi device with a set of popular tools made in python a database and RRD tool

RDF Equipment Ideas for VHF Foxhunting and Radio-Orienteering. This information is primarily for the Amateur Radio two-meter band

Book on CW paddles, history of keyers, keyboards, oscillators, and all things related to automatic Morse code.

H44MS is call of DL2GAC during DX vacations in Solomon Islands 1.Febr. to 30.April 2015

QSO Recorder Indexing service. This site allows radio amateurs to share their contest and DXpedition audio recordings, usually made with the N1MM Logger+ and the Qsorder plugin

_Amphenol RF_ manufactures RF connectors, RF adapters, RF attenuators, RF cable assemblies, and RF terminators. The company offers custom RF solutions, including modified connectors and integrated cable assemblies. Product examples include SMP to SMPM adapters, surface-mount SMB jack connectors, end-launch SMA bulkhead connectors, and non-magnetic SMPM connectors. The company's product portfolio also features single-crimp N-Type connectors, USCAR compliant Mini-FAKRA connectors, 2.4 mm to 2.4 mm adapters, and 2.92 mm plugs for 0.141-inch cable. _Amphenol RF_ produces MMCX and MCX cable assemblies on RG-316 and RG-174 cable, PFAS-free SMA connectors, and FAKRA rear mount bulkhead plugs for RG-58 and LMR-195 cable. Additional offerings include 2.92 mm to 2.92 mm adapters, BNC bulkhead jacks, SMA to MHF 4 LK cable assemblies, and 2.92 mm to SMA adapters. _Amphenol RF_ is headquartered in Danbury, Connecticut, and operates as part of _Amphenol Corporation_. The company maintains a global manufacturing and distribution network. DXZone Focus: RF connectors | Cable assemblies | Danbury, Connecticut | _Amphenol Corporation_

Extended Double Zepp measurements for all ham bands, and online calculator. The antenna is constructed much like an ordinary Dipole antenna but with 5/8 Wavelength Elements matched with an added Impedance Matching Section of balanced feed line

Large collection of 1900's antique Radios for sale,Floor model, Cathedral, table top, Novelty, Battery, police and broadcast band image gallery

A project for a 5-over-5 stack on 10 meters

FreePCB is a free, open-source PCB editor for Microsoft Windows, released under the GNU General Public License. It was designed to be easy to learn and easy to use, yet capable of professional-quality work.

Article on portable HF antenna where author diverge about antenna efficiency versus size based on his personal experience on using HF antennas during portable operations

The Washington County Amateur Radio Club (WCARC) was formally established on June 26, 2014, serving amateur radio operators and enthusiasts in Washington County, Texas. The club provides a local community for hams to gather, share knowledge, and participate in various radio activities. Its formation date indicates a relatively recent establishment within the amateur radio landscape. The WCARC aims to foster interest in amateur radio, offering a welcoming environment for both licensed operators and individuals new to the hobby. Membership is open to anyone with an interest in amateur radio, promoting engagement across different experience levels. The club's activities likely include regular meetings, field operations, and support for emergency communications within the local area.

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.

Antique and Vintage Speaker Restorations for over 35 years. Grunow,Atwater Kent,Fairbanks Morse,McMurdo, Stewart Warner,to name a few.

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

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.

A polarity checker is a very useful item to have around the shack and in a go-kit. This project, inspired by a QST article on powerpole connector protection illustrate how to build a polarity checker.

This article introduces an Arduino-based QRP CW Transceiver designed for lower HF bands. The journey begins with the Wotduino, evolving from a keyer to a multi-mode beacon. The development includes a QRP transmitter and culminates in a receiver inspired by Roy Lewallen design. The transceiver, controlled through a control bus features a signal path, modulation, filtering, and adjustable frequency settings. Despite initial testing intentions, successful QSOs on 80 and 40 meters showcase its functional capabilities.

Simple soundcard interface that can satisfy several requirements like totally isolated AF interface, Totally isolated PTT and CW Key interface, Extend Accessory connector to interface to allow easy connection of TNC and provide a solid PTT or SEND connection

The Eagle Radio Group Mablethorpe England United Kingdom

Since 1992, MATsolutions has delivered the assurance our clients need when acquiring, maintaining, and managing high-quality test and measurement equipment. Used Electronic Test & Measurement Equipment Sales, Calibration, Repair & Services

Probemaster manufacturers probes of all kinds, including oscilloscope probes, differential probes, test leads and much more, all proudly made in the USA

DMR Handheld TDMA Tier I and Tier II VHF or UHF product review with information on accessories

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.

If your multiple transceiver station is suffering of intrastation interference, this handy and inexpensive band pass filters and help you. QST article Sept 1988

Web site and blog that reviews equipment, goes over safety, and display projects being built. Includes Yaesu FT-891 and Ameritron RCS-10 Review, a 555 Morse Code Practice Oscillator, and and arduino based Morse Code Practice Oscillator

A multi section article on learning the morse code for beginners. The article include a list of tips the author consider to be uesful when someone want to begin the trip to learn the morse code.

A homebrew 13 elements yagi antenna for two meters band. These project includes two model of the same antenna with a 6 and 7 meter boom length. Detailed pictures and nec files are available for download

Free windows application for RF Microwave and Wireless applications. AppCAD is useful for the design and analysis of many circuits, signals, and systems using products from discrete transistors and diodes to Silicon and GaAs integrated circuits. AppCad is a unique suite of RF design tools and computerized Application Notes to make your wireless design job faster and easier

International DXpedition To The Sultanate Of Brunei February 6th To February 18th, 2019 A low-bands-focused DXpedition

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.

How to use AI (Artificial Intelligence) to identify Radio signals using a RTL SDR dongle and Linux (Ubuntu). This solution implement a framework using Keras and TensorFlow to learn and recognize the RF signals.

A homemade MFSK16 APRS HF tracker, worked pretty well for 1.5W on a Lipo supply with only 2 of the 3 BS170 FETs in the final

Undertanding the velocity factor in coax cable feed lines. Meaning of the veolcity factor index related to the RF speed of a signal inside the coax cable.

A unique, easy-to-use Amateur Radio program for creating County, State, Section and Grid Locator outline maps of North America that can be filled by Hand, from a Contest Logger UDP Feed, or from Imported ADIF or Cabrillo Logs.

A dual band X-frame wire antenna made using 4 turns for response down to 3 MHz or so, and 2 turns (switched) for response up to around 18 MHz. The loop configurations are tuned using common eBay 365 pF tuning caps.

This is a Bourne Shell script that will automagically download the FCC Amateur Radio license database, parse it, and populate a MySQL database. The database can be searched using the command line and is very fast.

The author investigated electric field antennas and achieved promising results with a shortened active whip antenna (30 cm). The findings suggest that at LF, active whips function primarily through electric field capacitance coupling.

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

Review of Yaesu VX-3R 2 m/70 cm FM transceiver. Receives 0.5-999Mhz AM/FMN/FMW, Transmits 144-148 and 430-450Mhz VHF/UHF FM.