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A j-pole antenna plan with drawings and dimensions that can help you on building your own j-pole antenna for the six meters band

A Western Pennsylvania Radio Guide

This will show you how to add a RF power amplifier to your Proxim Symphony for under $50. The cost is reduced by using the existing components on the Symphony, such as the PIN diode switch, and just inserting a higher power final amplifier. Increase the RF output power of your wireless network card to 1 Watt.

This transmitter covers the 160, 80, 40 and 20 metre bands and provides both SSB and properly generated CW. The CW side of this transmitter is not compromised and produces excellent CW. On SSB the audio has been tailored to provide a rising response to 3 KHz, with a sharp drop above that frequency. There is RF speech clipping to both provide more "punch" and to limit the peak output.

Testing the Icom IC-7700 on the mediumwave broadcast reception by VA7OJ

A very essential j-pole antenna for 144 MHz. To adjust the SWR you will have to play with the 40mm distance between the coax feed and the braid inner conductor connection

Echelford amateur radio society is based in ashford, middlesex, uk. has about 80 members.

S.C.A.R.T is a club based in the Southampton area of the UK open to everybody who is interested in amateur television and video related subjects.

Station information, Morse CW information, antenna photos

University of Bristol Amateur Radio Society

A simple and effective sleeve type balun is easily built. This Balun can be adapted to any band. While the dimensions are not critical ( +/- 10%), it is still basically a mono band device

Uderstanding Single Operator two radios amateur radio contesting mode, an article by CT1BOH

An home madek Audio CW Filter made simply using SMD Components

Torbay Amateur Television and Microwave Group GB3TB 23cms Repeater at IO8ØFL

A ham radio home made preamplifier for 50 MHz and 70 MHz bands

This is an open repeater for everyone to use. Auburn Hills, MI

The Icom IC-7700 spectrum scope feature a minimum resolution bandwidth of just 100 Hz and provide also an accurate vertical amplitude tracking permitting to use the 7700 as a bench spectrum analyser.

This is some general information about the lowell amateur radio club!

Antenna most often used by Hams around the world. Inexpensive, effective and easy to build, what more could anyone ask for in a home made antenna.

Association of NC State University alumni who are amateur radio operators.

Risca and District Amateur Radio Society Tredegar Terrace Risca Nr Newport

This stacking offers a well known simple phasing technique. All elements can be fed in parallel by open wires provided that they are fed in phase. This can be achieved by twisting the open wire phasing-lines at 180 degrees.

Book on CW paddles, history of keyers, keyboards, oscillators, and all things related to automatic Morse code.

Mounting on roof at the right ground level can greately impact on antenna performances because will affect the radiated angle of energy.

A list of announced DX operations compiled by VA3RJ

Duoband Yagi 2m/70cm with 4 Elements on 2 m and 5 Elements on 70 cm and one Feed point. The 4-El.-Ultralight-Yagi for 2m can be used on 70cm with an SWR of 1,5 without any changes.

A 50 MHz stable and small power amplifier, suitable for portable and domestic use. This RF Power amplifier delivers 900W with used pair of tubes primary installed into amplifier.

DXFile is a Windows shareware application designed for amateur radio operators, providing comprehensive log management capabilities. The software, developed in Pascal, facilitates real-time and deferred QSO entry, automatically populating fields like frequency, mode, and DXCC country based on user input and system time. It includes features for searching, modifying, and deleting QSO records, with options to sort logs by date, callsign, or entry order. The program offers various printing functions, including QSL card labels in multiple formats, and can generate standard logbook printouts. Beyond basic logging, DXFile integrates modules for tracking progress towards major operating awards such as DXCC, _IOTA_, WAZ, WAS, DDFM, and DIFM. It provides detailed summaries of contacts by band and mode, including graphical representations of HF traffic. A dedicated QSL Manager module assists in processing received QSLs, allowing users to mark confirmations and print multi-line QSL labels. The application also incorporates a DXCC list viewer, which can be updated to ensure accurate country and zone data for logging and award tracking. A distinctive feature is its HF propagation prediction module, which calculates optimal frequencies and signal levels for paths between **250 km** and **6000 km**, considering both E and F layer ionospheric conditions. This module helps operators determine the best times for long-distance contacts. Additionally, DXFile includes a _Web-Cluster_ interface, enabling connection to various DX cluster servers like DXLITE, DXSCAPE, and NC7J for real-time spot information.

This app will generate a QSL card design based on the input paramters as a PDF. Fields marked by a * are required, but the rest are optional. The options at the bottom allow you to customise the look and feel of the QSL card. If you would like, you can also download the LaTeX source file and customise it.

A list of links on Crystal Radio projects and related reources

G0TRG - Trafford England

Modification to an old cellular phone base station modules, with a fairly reduced output power (10 watts or so), the stock power amplifier modules will cover the 2.3 GHz and 2.4 GHz amateur radio bands.

Dominica Island 2011 by DL7JAN

This is a simple 2.4 GHz SWR meter which is based around surplus microwave hardware which can be easily found. The main component is a MECA -20/-20 dB Directional Coupler which has a frequency range of approximately 700 MHz to 2.5 GHz.

This web page is part of a self-help program for licensed amateur radio operators and radio pirates.

Sint Maarten by K1GI (PJ7I) 7L4DXT (PJ7XK) - 18 to 24 Nov 2012

The Bishop Auckland Radio Amateur Club

Home made 40 meter transceiver project. The receiver is a Progressive Receiver with a few modifications. The Transmitter is a modified MFJ Cub circuit. Includes schematic and circuit diagrams for Receive Input Filter, 3-Pole 500 Hz Cohn Filter and 7 MHz Double Tuned Bandpass Filter

Operating within the low-frequency spectrum, transformers serve critical roles in antenna systems, particularly for 160m applications. The resource details the construction and performance of 1:1 transformers built on BN-73-202 cores, emphasizing their use as hybrid combiners or phase inverters for RX antenna arrays. Measurements reveal that these transformers exhibit minimal losses, around 0.12 dB at 1.8 MHz, with variations based on wire type and number of turns. The analysis includes comparative data on transformer performance, highlighting the impact of different winding techniques on frequency response. Notably, the use of coaxial cable for winding improves bandwidth while maintaining low-frequency efficiency. The resource also discusses braid breaker transformers, which minimize inter-winding capacitance, achieving low losses around 0.21 dB at 1.8 MHz. These insights are crucial for optimizing low-band antenna systems, allowing operators to make informed decisions regarding transformer design and implementation.

The club is based in the Newhey area of Rochdale in North West England at the Ellenroad Steam Museum.

This multiband transverter project features power output at 13,8V 50MHz 15W, 70MHz 10W, second harmonic < 65dBc. Single N connector of antenna, suitable for a dual band Yagi. Article include Block Diagram for Dual Transverter and low pass filters

First released in 1988, _SWLog_ is a comprehensive suite of applications providing logging and remote control for both amateur radio and shortwave, utility, and broadcast listening. It integrates program schedules from sources like _HFCC_, _ILGRadio_, and _EiBi_ for broadcast reception, while also linking with amateur radio logbooks such as _ClubLog_, _eQSL_, _QRZ_, and _LoTW_. The software supports radio control for various transceivers, including _Flex_, Icom, Yaesu, and Kenwood, alongside interfaces like _FLRig_, _OmniRig_, and _HamLib_. Mobile applications for Android and iOS facilitate on-the-go logging and remote control, seamlessly transferring logs without manual ADIF export. _SWLog_ leverages an enterprise-grade relational database (SQL Server) for robust data management and analytics, enabling features like mapping QSOs by band or state. It offers specific integrations for _POTA_ monitoring, displaying active spots with real-time propagation and automatic radio tuning. The application's scalability allows multiple users to log to a centralized database, suitable for Field Day or DXpeditions. The user interface features modern aesthetics with light, dark, and gray themes, the latter optimized for outdoor visibility during activities like _POTA_ or _SOTA_. The Plus Edition, available for an annual fee, expands capabilities with advanced QSL integration, additional map providers, and enhanced propagation calculations using _VOACAP_.

The author has build the Hermes-Lite SDR v1 and v2 versions describing with a very accurated text and picture the process. Additionally has documented measurements for each component

A SSTV interfsace (soundcard) to minimize RF feed back and a soundcard limiter to prevent over driving the soundcard

A home mande spectrum analyzer project with several pictures and disposition of components boards based on a project by S57C

This page provides a list of UK scanner frequencies, specifically focusing on the Police UHF bands. It is a useful resource for hams interested in monitoring and listening to police communications in the UK. The page offers a detailed breakdown of frequencies used by the police, allowing hams to stay informed and connected to emergency services in their area.

Common-mode chokes are useful solutions for RFI reduction. Winding a few turns of coaxial cable on the FT 240-31 toroid can reduced the noise below the received noise floor. In this article author measure different chokes

Icom IC-R9500 Professional Receiver with 5 roofing filters, 48 kHz DSP

Review of the excellent ICOM IC-R8600 Wide Band SDR communications receiver. Featuring Direct Sampling SDR below 30 MHz Hybrid Superhet / SDR above 30 MHz.