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St. Louis County Police Dispatch

A home made sweeping signal generator up to 2 GHz

Pictures taken during lifting of a Rohn antnena tower

High Power RF Amplifiers by Delta Sigma, Inc

Ham homebrew, software, and ham info

Grahams Goldcoast Australia Radio Scanner Frequencies

HF power amplifier project powered by GU-78B by SV8JE

A perfect companion for your Elecraft K1 or any other (not power hungry...) QRP rig

How to easy connect two Pc together with a laplink cable

This article provides a basis to brew your own emergency power pack depending on your needs and tastes.

ON6MU 4 A power supply using a BDX33

Optimising a typical G5RV antenna by VK1OD

If you have space constraint at your QTH for a HF antenna, you can try contructing this HF magnetic loop antenna for 40-20 meters bands

Towers by Tashjian, Engineering, Design and Manufacturing

This article describes the antenna for Low Frequency Beacon. It originally appeared in the "Lowdown" for Oct. 1999.

Class C tuned VHF power amplifier for the 6-meter band by ON6MU

Calculating Antenna Wind Load

This article explores the Cobra Junior linear loaded antenna for 80m to 10m bands. This antenna is a linear loaded dipole described by W4JOH in 73 magazine June 1997

The 5/8 vertical it quite popular and matching solutions can vary

SM5BSZ article on building VHF RF amplifiers

Raspberry Pi WebSDR Receiver Project running SoftRock Lite ii Receiver (40m) and Raspberry Pi Model B

Interesting post with a practical video of using solar panel with a yaesu ft-857.

Operating in the Nordic region often requires specific call sign lookup tools, and this resource offers a dedicated search service for Swedish amateur radio operators. Users can query the database by entering a call sign, a family name, or a city, facilitating the identification of hams within Sweden. This functionality is particularly useful for DXers attempting to confirm contacts or for local hams seeking to connect with others in their area, leveraging the official data provided by the Swedish Amateur Radio Society (_SSA_). Such a lookup service streamlines the process of verifying contacts for awards like _DXCC_ or for general QSLing purposes. While many global callbooks exist, a national service like this often provides more granular and up-to-date information for its specific region. The ability to search by city can be especially beneficial for local rag-chewing or for coordinating activities within a specific geographic area, offering a practical complement to broader international databases.

Ham radio tower project by VK6YSF

20 Watt Power Amp for Softrock or for QRP transceivers by M0RZF

RF and Microwave Power Amplifier and Transmitter Technologies, amplifierlinearity, efficiency and available RF power devices.

The Collins 516F-2 is a heavy-duty power supply for the KWM-2/2A transceivers and the 32S-1,2,3 series of Collins transmitters.

Simple circuit, with a simple push, transmit a memorized Cw messages

EWE Antenna plan with a 9:1 balun

Many NDB radio enthusiasts publish their reception logs on the web. A completely separate system designed for individual listeners to make their own logs and obtain statistics on NDBs, DGPS and now Navtex Stations they have received. Log listings can be exported in a multitude of formats and then emailed to the NDB List

DX_Central, a compact desktop application, provides amateur radio operators with critical propagation data by aggregating solar statistics and imagery from various authoritative sources. This includes real-time information from agencies like NOAA and NIST, offering insights into current space weather conditions that directly impact HF propagation. The software is designed for both Linux and Windows operating systems, making it accessible to a broad range of hams. It presents a concise overview of solar activity, which is essential for planning DX operations and understanding band openings and closures across the HF spectrum. Operators can utilize the displayed solar flux index, K-index, and other relevant parameters to make informed decisions regarding their operating times and target bands, optimizing their chances for successful long-distance contacts.

Echos of USAF (Formally NAVSPASUR) radar signals reflected off of meteor trails received at Roswell, New Mexico

RF Power Meter using for reading a standard Digital Voltmeter by Iulian Rosu, YO3DAC / VA3IUL

A complete DIY Raspberry Pi Weather Station including software, capable to read wind speed, wind direction, rain gauge and with a temperature and humidity sensor along to a camera.

This article describes a simple Inverted L antenna for the HF bands designed to work on 80m, 40m, 30m and 20m

PCB for the DJ9BV Power Meter taken from DUBUS 3/87

A power line noise eliminator designed to eliminate QRN expecially on 40 meters band.

This small, light weight digital SWR and power meter uses an Atmel AVR Butterfly demo board and a Stockton type directional coupler.

This little project will make a portable 28 Volt DC power supply using two 12 Volt, 4.5 Ah rechargeable lead-acid batteries

Online database: downloadable database, updated monthly. In norwegian.

FreqTweak is a tool for FFT-based realtime audio spectral manipulation and display for Linux, offering various algorithms for audio processing in the frequency domain and an interactive GUI. It provides high-resolution spectral displays like scrolling-raster spectrograms and energy vs frequency plots.

This article explores the performance of an unloaded elevated vertical, base matching and feed line as a multi-band HF antenna system.

scanner dealer

This article examines the performance of the Ameritron AL-811H amplifier with the supplied 811A tubes and with 572B tubes, and details a procedure for replacement of existing tubes.

Germany's International Broadcasting Station with links to numerous pages in multiple languages containing program schedules, and live audio feeds.

How resolve low power problems on Icom IC-7000

Using our components you can build a rotating tower with greater capability than 3-4 static towers. A rotating tower allows common rotation of HF stacked arrays, VHF and UHF arrays, and antennas mounted at optimum heights. Component design also allows tower shunt loading and end support for wire antennas

Analysis of an antenna trap where a coil is formed of a length of coax cable, the outer conductor of one coax end is tied to the inner conductor of the other coax end, and the remaining connections form the terminals for the trap.

This article explores the performance of an unloaded vertical as a multi-band HF antenna.

Windows program for analyzing vertical antennas. This program shows the resistance and reactance to be expected looking into a cylindrical metallic tower over a perfect ground. It gives a useful approximation of the values to be expected in a real-world situation.