Search results

Operating magnetic loop antennas requires careful consideration of RF safety, particularly regarding near-field magnetic field intensity. This resource presents calculations for magnetic field strength (H-field) at various distances from a magnetic loop, emphasizing that the H-field is significantly higher than the E-field in the near-field region due to the inductive nature of the radiating element. It provides specific formulas and examples for determining safe operating distances based on power levels and loop dimensions, crucial for compliance with RF exposure limits. The analysis compares calculated H-field values against FCC and ICNIRP maximum permissible exposure (MPE) limits for controlled and uncontrolled environments. It demonstrates that even at QRP power levels (e.g., 5W), the H-field can exceed MPE limits within a few feet of the antenna, necessitating greater separation distances than often assumed for electric field considerations. The practical application of these calculations helps amateur radio operators configure their stations to ensure personnel safety and regulatory compliance when deploying compact, high-Q magnetic loop antennas.

Using a PC with soundcard as a VLF receiver, how to use your PC as a receiver for narrow-band signals in the VLF radio spectrum by DL4YHF

This resource examines the appropriate use of /M (mobile) and /P (portable) suffixes in amateur radio callsigns, specifically within the context of the UK Amateur Radio Licence. It addresses common ambiguities and challenges in determining operational status, such as operating from a summit or while walking. The discussion references the licence version in force before February 21, 2024, noting that while current regulations recommend but do not specify suffix use, the prior definitions remain relevant for understanding common practice. The content dissects key sections of the licence, including "Notes to the licence" (d)(i-iii) which outlines /A, /P, and /M usage based on location, and "Temporary Location" (jj) which defines /P operations. It also clarifies "Mobile" (17(1)(x)) as operating in or on a vehicle, on a pedestrian, or on a vessel on inland waters. The author provides examples and recommendations for choosing between /M and /P when both might apply, such as when operating from a parked car with a deployed mast or using a handheld on a summit. Historical notes from M1MAJ, G8ADD, and G6MZX are included, tracing the evolution of suffix rules from pre-BR68 days to the 1977 licence version. These historical perspectives highlight how past regulations have influenced current interpretations and persistent myths regarding /M usage. The resource emphasizes making an informed choice based on the licence and communicating the station's operational circumstances clearly.

McMinn County Amateur Radio Club, Inc. (MCARC) Club Callsign KF4CFO.

Homebrew your PC sound card to radio interface with this circuit obtained from the pages of Ernie Mills WM2U.

Joe Carr's Radio Tech-Notes Installing Coaxial Connectors

ECARA is a non-profit organization dedicated to the public service and promotion of amateur radio, and is affilated with the American Radio Relay League.

Ham Radio cartoons of common situations

Home of Charleston Amateur Radio Society

Accessories, Antennas and Battery chargers. Radiators, Repeaters, Yagi, Mag, Car, Tetra, Marine, Multiband, Brackets, Mounting accessories, cables and connectors, radiokits, special cables etc. Based in Finland

Otsego County amateur radio association

Practival project that contains two isolation transformers, one for AF from the tranciever to the line in on a soundcard, and one from the audio out of the soundcard back to the mic / data input of the radio. Both of which are variable inside the interface via two preset resistors.

Promoting Amateur Radio in Kitsap County Washington

Installing mobile radios in your new megabucks car can be a frightening proposition - especially if RF from your rig could damage your shiny new roadster

GCARA is a general interest amateur radio club intended to promote amateur radio, electronics education and fellowship through amateur radio in the Greater Cincinnati Tristate - Indiana, Ohio and Kentucky area. The club service area lies within a circle having a radius of 25 miles from downtown Cincinnati.

Piedmont NC ham radio and scanner information.

The 9W2VVH blog documents the amateur radio journey of Hussairy, focusing on his station setup and operational experiences from Malaysia. Content includes details about his _Yaesu FT-857D_ transceiver, which serves as the primary rig for HF, VHF, and UHF operations, often paired with a _G5RV_ antenna for HF bands. The site also features discussions on various aspects of ham radio, such as antenna experimentation and QSL card exchanges, reflecting a hands-on approach to the hobby. Operational updates frequently cover DX contacts and local ragchews, providing insights into propagation conditions and operating techniques from Southeast Asia. The blog serves as a personal log and sharing platform, showcasing the practical application of amateur radio equipment and fostering connections within the global ham community.

SCCARA was formed as a general interest amateur radio club in 1921 and became a non-profit corporation in 1947.

The Cuyahoga Amateur Radio Society (CARS) is a not-for-profit organization comprised of Amateur Radio (Ham Radio) operators dedicated to furthering the art of Ham Radio and to serving the public in times of disaster

Local amateur radio clubs often serve as vital hubs for hams to connect, share knowledge, and participate in group activities. The Orleans County Amateur Radio Club (OCARC), operating under the callsign WA2DQL, provides a focal point for amateur radio operators in Albion, New York, and the surrounding Orleans County area. These organizations frequently host events, offer technical assistance, and foster camaraderie among members, supporting various aspects of the hobby from contesting to emergency communications. OCARC's activities include discussions on proposed Technician class privileges for **80, 40, and 15 meters**, indicating an interest in regulatory changes affecting entry-level licensees. The club also promotes the use of online tools like _Radio Mobile Online_ for antenna pattern analysis and _VOACAP Online_ for propagation predictions, aiding members in optimizing their station performance. Furthermore, OCARC highlights participation in _Parks On The Air_ (POTA) events, such as the Erie Canal Bicentennial Celebration in 2025, encouraging outdoor operations and public engagement with amateur radio.

Soundmodem is a free software defined dual-port Packet-Radio TNC that implement a soundcard as a modem and supports AX.25 protocol. Soundmodem has been tested on Windows XP, Vista, 7, 8, 10 and has proved stable in operation. The Soundmodem may be used to build EMCOMM, APRS, BBS, Node station, for satellites

Personal Blog devoted to ham radio topics, amateur radio issues, social impact of ham radio and opinion.

This page describes how to set up RaspBerry Pi Linux system with already configured AX.25 softwares on SD or micro SD cards

The Atmel AVR Butterfly is a credit card sized board which contains an AVR MEGA169 processor, a six character LCD display, a five way joystick navigation switch, a piezo speaker, a 3 volt lithium battery cell for power and a few other odds and ends.

The KnightLites QRP Association is a world wide fellowship of low power (QRP) amateur radio communications enthusiasts founded in 1996, and is coordinated through the efforts of a small group of radio amateurs located in the Research Triangle region of North Carolina in the United States.

The Araucaria DX Group, based in Brazil, functions as an amateur radio club specializing in **DXpeditions**, **contesting**, and organizing various related events. The group actively sponsors contests and provides resources for DX enthusiasts. Its primary focus is on facilitating and participating in long-distance radio contacts and competitive operating events, contributing to the global amateur radio community. The group's activities include coordinating expeditions to rare DX entities, participating in major international contests, and fostering skill development among its members. By sponsoring events, the Araucaria DX Group supports the growth of amateur radio in South America, encouraging participation in competitive operating and promoting the pursuit of DX. The group's initiatives aim to enhance operational proficiency and expand the reach of amateur radio communications.

This is the downloads area for slides, plans and handouts for CARS Amateur Radio Licence Training Courses

Free windows software to program or reset cara ht olinca th888a and th888S th888 th10 th2100 th2uv th9 handheld VHF UHF two way radios

October 2003 QST article on working digital mondes with sound card interfaces

The _Sci.Electronics FAQ: Repair: RFI/EMI Info_ document, authored by Daniel 9V1ZV, provides a detailed analysis of computer-generated RFI/EMI, focusing on its impact on radio reception. It identifies common RFI sources such as CPU clock rates (e.g., 4.77 MHz to 80 MHz), video card oscillators (e.g., 14.316 MHz), and even keyboard microprocessors, all of which generate square-wave harmonics across HF and L-VHF regions. The resource outlines a systematic procedure for pinpointing RFI origins, including disconnecting peripherals and using a portable AM/SW receiver with a ferrite rod antenna to localize strong interference sources. The document categorizes RFI mitigation into shielding, filtering, and design problems, offering practical solutions for each. It recommends applying conductive sprays like _EMI-LAC_ or _EMV-LACK_ to plastic casings of radios, monitors, and CPUs to create effective Faraday cages, emphasizing proper grounding and avoiding short circuits. For filtering, the guide suggests using line filters, ferrite beads, and toroids on power and data lines, and small value capacitors (e.g., 0.01 uF for serial/parallel, 100 pF for video) to shunt RFI to ground. It also discusses the use of bandpass, high-pass, low-pass, and notch filters on the receiver front-end or antenna feed to combat specific in-band noise.

QSL Cards from the past, ham radio QSL Card collection by W8JYZ

C.A.R.L.A. is a growing network of repeaters providing coverage across Northern & Central California and Western Nevada. It is intended to be used as a reliable communications resource during significant local, regional and wide area incidents, and is open to all licensed amateur radio operators

The Peekskill / Cortlandt Amateur Radio Association, Inc. (PCARA) is a Volunteer Non-Profit Community Service Organization Serving the Greater Peekskill / Cortlandt Area of Westchester and Putnam Counties in New York State. PCARA operates three voice repeaters in the Northern Westchester / Southern Putnam County region of New York State.

Non-profit public foundation dedicated to providing research and educational access to optical and radio astronomy. Located in Rosman, North Carolina.

Located in Johnson City, Tennessee - Washington County EM86.

Platinum coast amateur radio society (pcars) w4mlb - melbourne florida, pcars provides hf, vhf, and uhf communications for any police fire and rescue emergency

SCARA is located in Siskiyou County, CA. Features information on club events, meetings, and membership.

This website is made available to the CCARC Hamradio Community and to anyone interested in Amateur Radio.

The Mobileer group is for California Amateur Radio (Ham) operators to discuss family mobile radio caravan and camping trips.

The Cass County Amateur Radio Club is a Non-Profit Organization serving Logansport, Indiana 46947. The CCARC participates in ARES Nets, Skywarn Nets and Field Day and has 2m repeaters at 147.18 MHz, 145.23 MHz, and 145.35 MHz and a 70cm repeater at 443.65 MHz.

MF TeleType is a program for amateur radio digital communication via sound card, ham radio chat program for extra reliable text transmissions over long distance

Investigates the legal framework surrounding **pneumatic antenna launchers** in Victoria, Australia, specifically their classification under the Firearms Act 1996. The author, VK3KBC, details how these devices, designed to discharge a projectile by compressed air, are defined as 'firearms' and subsequently categorized as **Category E Longarms**. This classification carries significant penalties for unregistered possession or use, with the author noting the lack of provisions for amateur radio operators to legally possess and use such devices for antenna deployment. The author shares personal experiences needing such devices for portable HF radio operations, contrasting them with previously legal slingshots and current alternatives like kites or bow and arrow. VK3KBC outlines efforts to advocate for legislative change, including submissions to the Wireless Institute of Australia (WIA) and the Victorian Department of Justice, proposing an amendment to Section 3(i) of the Firearms Act 1996 to include amateur radio field operations as an exempted use. The resource also reviews the original intent of the Category E firearm classification, suggesting that pneumatic antenna launchers may have been assigned this category in the absence of a more suitable alternative.

Some modifications for the Tigertronics Signalink USB sound card radio interface

The South Canadian Amateur Radio Society (SCARS) is known throughout Cleveland County, Oklahoma

Presents an Italian association, Club 27 Catania, which is affiliated with Protezione Civile FIR-CB. The resource indicates a focus on CB radio and various DX groups, including Papa Alfa Tango, Wisconsin Michigan, Charly Tango, Oscar Sierra, Big Time Operators, WAC Club, Azteca DX, and TX&RX Group. The page itself is a placeholder, stating "We’re getting things ready" and "Loading your experience… This won’t take long," suggesting future content will detail the club's activities and affiliations. The current state of the resource provides minimal information beyond its name and affiliations. It does not offer details on club events, membership, technical discussions, or operational specifics. The listed DX groups imply a focus on long-distance communications within the CB radio spectrum, but no specific results, comparisons of operating techniques, or practical applications are available on the present page.

The C.A.R.E.N. Club is one of the oldest amateur radio clubs in Arkansas, dating back to the late 1950s. Just as the name implies, the C.A.R.E.N. Club is the state leader in emergency communications, SKYWARN, Amateur Radio Emergency Service (ARES), Radio Amateur Civil Emergency Service (RACES).

Hams or amateur radio operators and CB operators usually cannot have ideal grounds, but with some care and planning they can have nearly perfect systems

The purpose of this web page is to try to investigate some of the issues around ICOM IC-746PRO reported by many radio amateurs through out the world; and unfortunately not properly taken care of by ICOM.

Fellowship for all Amateur Radio Operators of Rockingham County. Home of the N4IV repeater system. Licensing classes, testing, ARES, and Skywarn