Search results

Hear VLF audio from NASA online VLF radio receiver in Huntsville, Alabama.

Listen to the Baltimore City Police Live Scanner Radio Feed.

A better way to install PL-259 connectors on RG-8X type coax by Dan Richardson, K6MHE

End-Fed Half-Wave Antenna for the 7 or 10 MHZ amateur bands intended to provide a very simple to erect yet effective portable QRP antenna.

Digital Master 780 is a windows multi-mode program which uses Ham Radio Deluxe for radio control. It is part of HRD package and support PSK, QPSK, Contestia, CW, DominoEx, Hell, MFSK, MT63, OLIVIA, RTTY, RTTYM, THROB and SSTV. Free version was made available with HRD 5.

Monitoring shortwave broadcast stations effectively requires accurate schedule information to identify transmissions. This online utility offers a straightforward, graphical interface designed to search for and display current shortwave radio broadcasting schedules. Users can precisely filter results by frequency, specific language, broadcaster, time of day, and even by shortwave band, which simplifies the process of pinpointing desired content. The database, last updated on March 26, 2023, details station callsigns (e.g., BBC), start and end times in UTC, days of the week, broadcast language, transmitter power in kilowatts, and azimuth. Crucially, it includes the precise geographical coordinates of transmitter sites, such as Woofferton in the UK or Al Seela in Oman. This data is invaluable for predicting signal paths and optimizing antenna direction for improved reception, a key consideration for serious SWLs. For instance, a search for BBC English broadcasts at 21:04 GMT quickly reveals multiple active frequencies like 17780 kHz from Woofferton, offering a clear overview of current transmissions. The tool processes queries rapidly, returning results within seconds, demonstrating its efficiency for broadcast listening enthusiasts seeking timely information.

Attic antennas can work better than you might think, some of mine work as well as their outside counterparts

Experience and practical use of magnetic loop antennas, by N0HC

Successful apartment operating starts with an evaluation of the location

This article describes how an effective ground system can be produced for a short vertical antenna.

Suggestions on finding RF ground when you live in an apartment and you want to setup an antenna

Over 16.7 million callsigns are indexed within the HamCall World-Wide Callsign Database, a long-standing resource for amateur radio operators. This online tool facilitates rapid lookups of callsign data, including operator details and QSL photos, which are crucial for confirming contacts and pursuing operating awards. The database integrates FCC updates as they are released, ensuring timely access to current licensing information. The platform also features a live **DX cluster** displaying recent spots across various bands, from 160m to 3cm, with specific spot counts for active bands like 15m (50 spots) and 10m (46 spots). Users can view **band activity** summaries, providing an immediate overview of propagation conditions and active frequencies. Additionally, the service provides access to a hamfest calendar and amateur radio news updates, making it a multi-faceted resource for daily operating and event planning. Since 1989, the HamCall DVD has supported this server, alongside HamCall.net Gold Memberships, demonstrating a sustained commitment to providing comprehensive callsign data.

The project details a DIY SWR/Wattmeter designed around an _Arduino Uno_ shield, providing capabilities to measure RF power from 2 to **200 watts** and Standing Wave Ratio (SWR) for HF amateur radio bands. This construction features a compact design, integrating the measurement circuitry directly onto a custom PCB that interfaces with the Arduino Uno microcontroller. Key components include a directional coupler for sensing forward and reflected power, precision rectifiers, and analog-to-digital conversion for processing RF signals. The Arduino firmware handles calibration, calculations, and displays the results on an integrated LCD, offering real-time feedback on antenna system performance. The design prioritizes simplicity for homebrewers. Performance specifications indicate accurate readings within the **2-200W** power range, suitable for typical QRP to medium-power HF operations. The project provides schematics and a basic overview of the software logic.

Two well performing 50 MHz antennas designed with W7EL EZNEC along to many other antenna projects and related articles

EH antenna for six meters band by IW0BZD

NGC is now distributor for COMET and MALDOL brand antenna products designed, manufactured in Japan. Distributor of DAIWA brand RF SWR/power meters and switching power supplies, antennas, test equipment, antenna analyzers and more

Homebrew VHF Yagi 50MHz 144MHz 432MHz 1296MHz 2320MHz 6M 2M 70CM 23CM 13CM Yagis

Setting up the Arduino DUE to run as an SDR software defined radio

Over 25,000 amplifiers and sub-assemblies were produced by Angle Linear for the communications industry over a 40-year period. The company specialized in **high-linearity RF products**, focusing on preamplifiers, bandpass filters, and receiver multicouplers. Specific product lines included PHEMT and GaAs FET preamplifiers, offering both quadrature and single-ended configurations for various signal levels. The offerings encompassed coaxial and combline bandpass filters, along with integrated filter-preamplifier assemblies. The company also provided custom RF assemblies, addressing applications such as MRI preamplifiers, passive radar, and EME (moon bounce). Their product range covered VHF and UHF frequencies, including specific designs for 2m, 70cm, and 23cm bands, often featuring high IP3 performance. Technical documentation, such as filtering application notes and duplexer theory, was also associated with their product offerings.

Live streaming audio of VHF marine radio channels 05A, 16, and 22A from NJ and NY City

Small HF balcony antenna project

FTBasic is a CAT control program for Yaesu radios FT100, FT817, FT847, FT1000MP Mark V and FRG100

K9AY loop antenna installed at PA6Z Contest group. This is a receiving antennas for the low bands (160m, 80m and 40m). Include schematics and info on a building the control box, preamplifier and low-pass filter

A large collection of maps of each dxcc country with general information, banknotes and coins, satellite images, flags and national information where available by SP6NVK

Circuit diagram and discription of 7 MHz Ham Radio SSB Transceiver. Transceiver using two MC1496, 4.43 MHz Ladder filter, LM386, LM324 and IRF840 in final.

Javascript for calculating the lengths of tubing to be used for the construction of a Super J-Pole in a collinear design

An on-line javascript calculator and quite a few pictures to show how to make a helix antenna.

VHF magnetic loop atenna by ON1DHT

A gamma match example

Telescopic fiberglass poles, tubes, special products for Amateur Radio stations suitable for ARES / RACES and other public service applications

Pictures and plans to build 70 cm yagi antennas

Listen to Boston Fire Department live scanner feed

Ham radio products, with on-line catalog and prices

Improve your 80 and 160 meter signal without a Yagi!

KA1FSB loop calculator give you a quick overview of the feasibility of "squeezing" a loop into your available yard or apartment space. The easy calculator yields a reasonable approximation of dimensions, to within 5% over the amateur bands, using typical wire gauges ranging from 12-18 AWG.

Dipole antennas, unique broadband antennas, trap dipole antennas, coils, accessories for HF radio

WCPO police scanner ohio - Boone County Police, Fire and EMS Dispatch. Cincinnati police radio scanner. Cincinnati Police Talkgroups for District 1-4 Central Business District dispatches as part of District 1 operations.

How to build a beverage antenna. How to deploy a BOG antenna for your next SWL DX-ing activity. Give it a try and follow the orientation tips for this bi-directional antenna.

PKW Antennas for ham radio bands, Quads, delta loops, log periodics antennas for military and professional use by Ditta Martelli fabbrica italiana antenne

A multiband jpole antenna

Packing crate HF antenna

Demonstrates the construction of a **remote antenna tuner** utilizing a standard radio-controlled (RC) servo mechanism to adjust a variable capacitor. The design focuses on enabling remote tuning for narrow-bandwidth antennas, specifically mentioning frame and packing crate antennas, from within the shack. It covers the mechanical arrangement for integrating the servo with a capacitor and provides a circuit diagram for a control unit that generates the necessary 0.5mS to 1.5mS pulse-width modulation (PWM) signals to drive the servo's 180-degree rotation. This setup was successfully tested with up to 20 watts RF power without arcing or adverse effects on the servo, though tuning was performed at 1 watt for VSWR readings. The resource highlights the use of inexpensive, readily available components, such as Futaba servos, and details critical considerations like power supply decoupling with a 47uF capacitor to prevent unintended servo movement upon power-off. The system provides a practical solution for optimizing antenna performance for specific frequencies without manual adjustment at the antenna itself.

A new perspective on the analysis and design of this popular antenna element. By Karl-Otto Muller, DG1MFT

Antenna Scatterers Analysis Program, is a Free general purpose antenna analysis software program for numerical electromagnetic antenna design, modeling and analysis. Source code and windows executables are available to download.

An easy to build antenna switch for long wire antennas, expecially designed for sloper antennas

CHIRP is a free, open-source, cross-platform radio programming tool that supports a large number of transceivers from manufacturers such as Icom, Kenwood, Yaesu, Alinco, Wouxun, Puxing, and Baofeng. Chirp radio software run on Windows, Linux, and macOS, enabling users to exchange data between different radio models and interface with multiple data sources and formats. The program streamlines the configuration of memory channels, frequencies, and various settings for amateur radio handhelds. Specific models supported include the _Icom IC-7300_, _Kenwood TH-D74_, and _Yaesu FT-818_, among many others. CHIRP provides compatibility with various file formats, including Generic CSV, RT Systems CSV, ARRL Travel Plus (.tpe), and manufacturer-specific formats like Kenwood KPG-44D (.dat) and Icom Data Files (.icf). Additionally, it integrates with the DMR-MARC Database for enhanced programming capabilities. Users can download CHIRP for their platform and access extensive documentation, including a FAQ and a mailing list for support. The project encourages users to consult existing documentation and open/closed tickets before submitting new bug reports or feature requests.

Conejo Valley Amateur Radio Club, article edited by Rory Eikland, KG6HCU and Ken Larson, KJ6RZ, they have had excellent experience building and using J-Pole antennas, and share their experience on planning VHF and UHF Jpole antennas.

ON6MU project for a vhf uhf preamplifier

Scanner master is a popular radio-scanner online dealer.

A short HF antenna by SM0VP0