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The Vibroplex Collector’s Page details the history and identification of Vibroplex semi-automatic telegraph keys, commonly known as "bugs." It traces the evolution from Horace G. Martin's 1902 Autoplex, which required a battery, to the fully mechanical Vibroplex patented in 1904. The resource explains how these keys generate automatic dots and manual dashes, helping telegraphers mitigate Repetitive Motion Disorder (RMD) and increase sending speed, thus improving their earnings. The site also covers the initial design by Alfred Vail in 1844, Jesse Bunnell's 1881 "Triumph Key," and William O. Coffe's 1904 "Mecograph." This page assists owners in identifying their Vibroplex models and determining their manufacturing dates, providing insights into the company's long history and notable figures like J. E. Albright. It notes that approximately 300,000 Vibroplexes have been produced since 1904, with the Original model still in production after more than 90 years. The resource also touches upon various Vibroplex models, including unusual, scarce, and common types, alongside legal and illegal clones from other manufacturers.

March/April 2010 will be QRV from March 16th till April 4th on IOTA NA-100, 6-80m - mainly in RTTY, PSK and SSB QSL via DL7AFS

DX pedition from Port Stanley, Falkland Islands (SA-002) calls : VP8BUG (digi-modes) and VP8BUH (SSB) QSL only via: manager EB7DX

San Rafael, CA ham radio club

AC7GZ/B is a converted Sharp CB-2460 Citizens Band transceiver operatin on 28.2118 MHz.

An end-fed half wave antenna matching unit made of 3:24 turns ratio on a FT140-43 toroid with a 150pF capacitor across the input.

This page is about the Ionosphere, how it was discovered, what it is, and what you can do with it.

Liga Amadores Radio Sintra

This magnetic loop DIY site is ment to be an introduction into making DX high quality magnetic loop antennas that will beat any dipole

The Primary N6OCS Repeater is located at 5700 feet on Santiago Peak in the Santa Ana mountains.

SDR as an RFI site survey tool. This article will show how a site survey tool was built to use in RFI mitigation.

A dynamic collection of high latitude geomagnetic data from 12 Canadian observatories

DF0WD/DL4YHF's Longwave Overview details amateur radio operations on the 135.7 to 137.8 kHz segment in Germany. The author outlines the "inofficial" European band plan, specifying segments for QRSS, TX tests, beacons, conventional CW, and data modes. Early LF activities at DF0WD began with a 20-watt CW transmitter, later upgraded to a homemade linear transverter capable of 100 watts, driven by an Icom IC706 on 10.137 MHz. The station's antenna system includes a 200-meter wire, approximately 10 meters above ground, supported by football field light-masts. Despite its length, the antenna's efficiency is noted as very low due to the immense wavelength of about 2.2 km. The author's experience highlights the significant challenge of achieving effective radiated power (EIRP) on LF, estimating DF0WD's EIRP at around 80 milliwatts based on field strength measurements from PA0SE. DF0WD/DL4YHF has successfully worked numerous countries on 136 kHz CW, including DL, F, G, GI, GM, GU, GW, HB9, HB0, LX, OE, OH, OK, OM, ON, OZ, PA, and SM. The author also mentions ongoing efforts to log contacts with CT, EI, LA/LG, and to complete a two-way QSO with Italy, demonstrating persistent activity on this challenging band.

Northern New Jersey, New York City/Long Island and Westchester County frequency coordination

Radioamadorismo ,amador, ciência, comunicação, rádio, hooby, experiências from Brazil by PY3AB

The RACES ARES Disaster Assistance Repeaters (RADAR) group was formed by a team of amateur radio operators dedicated to providing high quality repeater communications for amateurs involved in public service communications or response to emergency/disaster situations.

This page provides a list of scanner frequencies for hams in the UK. It offers a comprehensive guide for ham radio operators looking to find and tune into various frequencies for communication. The page is useful for hams who want to explore different channels and connect with fellow operators in the UK. Whether you are a beginner or an experienced ham radio enthusiast, this resource can help you discover new frequencies and expand your communication network.

Amateur Radio Amateur Radio Manuals & Books Computer Books & Programs Computer Hardware Rare & Hard to Find Books amateur radio,electronics ,electronis parts,tubes, amplifiers,towners, beam antennas and more

No matching adjustments needed. Directly perfect match to 50 Ohms using a remotely switched wideband transformer

A project to turn a Raspberry Pi into a very versatile tracker, digipeater and an iGate

Amarteur Radio Society Of India, the national society, is issuing Worked Republic of India (WRI) Award to VU and Dx operators.

W3FPR fixed level AF output fot the Elecraft K2

The BikeLoop antenna project details the construction of a double magnetic loop antenna optimized for VLF frequencies, specifically around 136 kHz. This innovative design incorporates two orthogonal loops, which significantly enhance reception capabilities. Key construction hints include utilizing lightweight bicycle rims for the antenna structure, making it easy to transport and set up in various locations. The document provides valuable mathematical and electrical insights into the antenna's performance, alongside practical reception tests conducted in the Italian Alps, showcasing its effectiveness in capturing various VLF signals, including Sferics and FSK transmissions. Proper setup is crucial for optimal performance. The project emphasizes the importance of grounding and avoiding interference from nearby electrical sources. The reception tests revealed the antenna's ability to capture a range of signals, demonstrating its practical application for enthusiasts interested in VLF reception and antenna experimentation. Overall, the BikeLoop serves as an excellent starting point for those looking to explore the world of VLF frequencies and enhance their antenna-building skills.

A review of the 30 meter MonoGap Antenna. This review covers from the unboxing go the Gap product, the assembly of the elements, the test and tuning phase and a performance report during the years

This article include a circuit that allows a cheap 0-1mA meter to be used as a micro-ammeter or a milli-voltmeter

This award is open to all Amateurs and SWLs

Eham users review of Radio Shack PRO-95

Documents S21RC's construction of an impedance transformer harness for a VHF/UHF cross yagi, utilizing 20m of _RG179_ cable. Details the creation of a DIY RF sampler with a -50dB sampling output, primarily for measuring HF radio PA section output with a Spectrum Analyzer, also applicable for _Pure Signal_ transmission. Chronicles the deployment of a 200m long beverage antenna for the _S21DX IOTA_ operation in 2022, positioned 2m above ground. Discusses the construction of a 3-element short beam for 10m to replace a previous 2-element antenna, with assistance from S21DW. Provides guidance on operating cheap _PA-70_ and _PA-100_ type Chinese SSPAs using IRF530 MOSFETs, emphasizing the necessity of a final LPF. Outlines the design and construction of a fully isolated interface for radio-to-computer connections, supporting various digital modes with isolated ground, audio transformers for IN/OUT, optical isolation for CAT/CIV, and isolated PTT/COS lines. Includes a log of software updates, such as the _HMI/TFT for NX8048K070_ and _2.1.14 Lite_ release with bug fixes for PEP hold and gradual watt decay.

How to add the YF-122CN 300 Hz CW filter or YAESU XF-119SN 2,3 Khz SSB filter in the Yaesu FT-857

The magnetic loop, thus named by the use of the magnetic component of the electromagnetic field, is a parallel circuit LC. In this article a sample project to home made a custom antenna. The circular form is often met on the commercial models but this antenna can be hexagonal, octagonal or square.

UK frequency list provide reference table to lister to Police scanner channels UHF VHF, Amateur Repeaters, Ambulance CB Radio CoastGuard Rescue, marine VHF, Military and more.

The TRI-STATE emergency communications response team is dedicated to providing help to public service agencies with communications when normal communications are not working.

The Japan Amateur Radio web journal, CQ Web is a portal to radio related japanese resources established in 1995

YU7EF EF0206 2m Band 6 Element Yagi Antenna project, provides 11.8 dbi gain

New Zealand Association of Radio Transmitters Auckland Branch 02

These were some of the steps I took to setup my Allstar link node/server and some of the modifications that I did to it.

Details the history and cessation of the Amateur Radio Association of Bahrain (ARAB), operating under the callsign **A92C**. Established in 1970, ARAB functioned as the primary representative body for amateur radio enthusiasts within Bahrain for several decades. The organization facilitated various amateur radio activities and provided a central point of contact for local hams. The resource indicates that ARAB ceased operations due to unspecified circumstances. It explicitly states that the organization is no longer active, marking the end of its long-standing service to the Bahraini amateur radio community. Information regarding a newly formed society, open for membership, is provided, with contact details for Fawaz, **A92AA**, for further inquiries about the successor organization.

marine and weather station products

Taken from: Brief History of Amateur Radio in Calcutta-by Avinash Missra, VU2EM

Wakulla Springs, Florida U.S.A.

Product information, resources, enhancements and links of the popular ICOM IC-756PRO III

Alcatel Amateur Radio Association

The club was founded in 1987 when a group of ham operators hauled radio gear, antennas, and a generator to the island by boat to operate portable during ARRL Field Day

A.I.R.A. is chartered by the State of Illinois as a non-for-profit corporation and has been in existence over 21 years

Live webcam images, still pictures and movie clips over an HF SSB channel. NBTV (Narrow Band Television) is a technique with some similarity to SSTV, and some to conventional FSTV

An introduction to NPR by Daniel Estevez. In this blog article Daniel EA4GPZ / M0HXM, introduce the new IP communication protocol over the 70 cm amateur radio band. Daniel is an experienced operator on IP on 430 MHz with CC1101 and Beaglebone black project and makes a good comparison of the two projects.

Founded nearly 40 years ago at the Pie Hall, Denby Dale, a village famous since 1788 for giant pies.

Exaustive review of the self-contained, top-performance HF/6m transceiver Icom IC-7700

Home page for the TARPN node design and promotion. This is an Off-The-Grid Text messaging and educational packet networking project. No Internet required or desired.