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This article was first published in CQ-TV issue 208. Author try to explain digital television in layman's terms and without getting too involved in mathematics.

Passive Band-Pass Filter, low-pass filter calculator

WA1ION article on beverage and ewe antennas

A simple drawing schematic of a portable field dipole for 14 MHz with dimensions in meters and instruction for setting up the antenna and to store the radial for easy transportation

Activities, legal infos, technical articles, photos, vendors, software, and links

Cool QSL - QSL Card printer

Manufacturer of transformers, inductors coils and chokes. Custom winding, EMI / RFI Filters, Antenna Windings on ferrite rod, Antenna Winding on phenolic. Any antenna coil designs.

A helically wound vertical antenna experiment. 14 meter of wire wounded on a 8 meter fishing pole with 4 elevated radials

Display and Send Hellschreiber On Your iPhone and iPad - iPhone / iPad app to send and receive Hellschreiber

A Linux Smith charting program. You can enter either discrete components or transmission lines, see the results on screen and/or generate Postscript output. Component values can be changed numerically or using scrollbar

The adventures of a small Contest Group

K9EID 75W power amplifier for the six meters

Linear amplifiers cold adjustments with network analyser (VNA)

Presents the Sacramento Amateur Radio Club (W6AK), detailing its long-standing presence in the amateur radio community since 1914. The club's affiliation with the **ARRL** is highlighted, indicating its adherence to national amateur radio standards and participation in broader organizational activities. Content includes recent operational activities, such as participation at the Yolo County Fairgrounds, and social gatherings like meet-and-greets at East Portal Park, fostering member engagement. The resource also provides insights into the club's governance, listing current board members and their **call signs**, including the President Mike McDermott (KF6RUQ) and Vice President Jay Ballinger (N6SAC). Information on past elections and board position fillings offers transparency into the club's operational structure. The site functions as a central hub for club news and event announcements, reflecting its role in coordinating local amateur radio endeavors.

If you find yourself in London then please do visit. The club operates a HF station with the call sign GX0MIN, Friday evenings. We have held the contest call sign M2W since 2000, and regularly participate in HF contests. CQWW SSB is a favourite and the group has operated the October event from Whitton using M2W and from DX locations during the years, with the calls 9H0WW, ZC4DX, C56DX, A45ZN.

A simple, cheap and easy to build 26 feet long vertical antenna that works DX on 20 - 10 meters including WARC Bands, it is designed for portability for field days, camping, or permanent installation, cost, and to achieve at least 1/2 wavelength on the WARC bands.

This circuit is very simple and has a fantastic range of potential uses.

Christoph Petermann DF9CY DRM demonstration receiver project including Circuit Diagram and component list

QSL collection from F5RRS

HF VHF UHF antenna ideas to be used for field days. All antennas are quick to set up and take down and offer proven performance and flexibility. Presentation offered by Mahoning Country ARES

A selection of speakers or headphones for use with amateur radio equipment. Includes an interesting paragraph comparing Dynamic and Electret Condenser Microphones, but also about audio Equalization.

Solar activity can aid or hamper HF propagation beyond line-of-sight range, WA1SVF and N6BV answers to questions about Sun influence on radio signals propagation

The construction principles for open-sleeve elements in antennas

The Southwest Missouri Amateur Radio Club, based in Springfield, Missouri, was incorporated in 1956 as a "benevolent organization" with the purpose of service to the community.

Aqui encontraras todo lo relacionado con la radioaficion de Puerto Rico

FTRestore is a free Windows desktop application to upload, download and compare memory channels and menu settings in the Yaesu FTDX1200, FTDX3000 and FT-991/FT-991A model transceivers.

Original article was in December, 1986 QST

Strictly Ham has a large retail presence in Australia and welcomes enquiries from New Zealand, the Pacific and Asia. Strictly Ham offers a comprehensive range of high quality Amateur, CB and Marine products at very competitive prices.

Online log search for 5W0M Samoa 2013

A collection of audio amplifier projects by N1HFX

In this article you can find solutions to the problem of keeping your ham radio antennas hidden from the CCR Police

Lewis County, New York

Announces the retirement of Brand Electronics, a manufacturer specializing in **power meters** and various ham radio accessories, effective 2025. The company has served the amateur radio community for over 35 years, providing equipment for station setup and operation. The product line historically included accessories compatible with major transceivers from Icom, Yaesu, and Kenwood, alongside components and technical references for homebrew projects. Their offerings supported accurate RF power measurement, crucial for optimizing antenna systems and ensuring legal limit compliance. This notice serves as a final update regarding the company's operational status, marking the cessation of manufacturing and sales activities. The site provides no further details on product support or inventory liquidation.

Essentially, a choke balun is designed to 'divorce' your antenna from the feed line. if your feed line is coaxial cable then you don't want it to be part of your antenna. you want to be able to deliver all your power to the radiator itself, i.e. 'the antenna'. a choke balun does this admirably

Fort Myers Amateur Radio Club is located in Fort Myers Florida. FMARC has around 300 ham radio operators.

160-10 Meters 1500 Watt Amp - W4NFR

Collection of ATV projects

Indiana's Premier Repeater Group An ARRL affiliated organization

This project is a Software Defined Radio Receiver. It has a frequency range of 24MHz 1.2GHz. It can demodulate AM, FM, USB, LSB with selectable bandwidths of 600, 2400, 2800, 3200 and 6400Hz. Using a simple RTL-SDR Dongle and Raspberry Pi 3 computer using GNU RADIO

The article, "Using 75 Ohm CATV Coaxial Cable," details methods for employing readily available 75-ohm CATV hardline in standard 50-ohm amateur radio setups. It addresses the inherent impedance mismatch and practical considerations, such as connector compatibility, for hams seeking cost-effective, low-loss feedline solutions. The resource specifically contrasts common 50-ohm cables like RG-8, RG213, and _LMR-400_ with 75-ohm hardline, highlighting the latter's lower loss characteristics, particularly at VHF and UHF frequencies. It explores two primary approaches to manage the impedance difference: direct connection with an acceptable SWR compromise and precise impedance transformation. The direct connection method acknowledges that a perfect 1:1 SWR is not always critical, especially when using low-loss coax. For impedance transformation, the article explains the use of half-wavelength sections of coax to reflect the antenna's 50-ohm impedance back to the transmitter, noting its single-frequency effectiveness. It also briefly mentions transformer designs using toroid cores and a technique involving two 1/12 wavelength sections of feedline for broader bandwidth. The content further clarifies the concept of _velocity factor_ for calculating electrical versus physical cable lengths, providing a generic formula for precise length determination. It notes that while half-wave matching is practical for 10 meters and above, it can result in excessively long runs for lower bands like 160 meters, potentially adding **250 feet** of cable. The article also mentions achieving a usable bandwidth of 28.000 MHz up to at least **28.8 MHz** on 10 meters with specific transformation techniques.

A postage-stamp-sized DSP microcontroller imbedded in the TNC-X eliminates the dedicated laptop or PC.

This walkie is sold without the wide band receiver enabled, this is, only 144 and 432 MHz band

ZK3N On-line Log search

The ZR6YY Antenna for 6m by Maurius ZR6YY revisited by YT1VP

5 Elements 12,5 Ohm Yagi with a 6m Boom

Home Brew 6 Meter Amplifier with a single 4CX250B by W4NFR

Simple Elecraft KX3 and PowerSDR configuration by AG1LE

Amateur radio operations during heartquake in italy

A 50 MHz homemade RF spectrum analyzer