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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

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

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!

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

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

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.

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 list of links on Crystal Radio projects and related reources

Dominica Island 2011 by DL7JAN

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.

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.

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

The Bishop Auckland Radio Amateur Club

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

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

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

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.

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

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

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.

Elkhorn Valley Amateur Radio Club Norfolk

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.

DL7AFS, Babs and DJ7ZG 5-19 November 2012

Departamento de Radio Escutismo do Nucleo Moinhos de Vento Portugal

Doing the MARS Mod on the TS890S. This will take care of any of your HF or Mars needs, and any new bands added in the future. You will now have the new 60m Band also. It is unclear if it will open up the 4m Band that some EU Countries are now allowed.

Personal web site by N9SKN about portable QRP operations with pictures of several portable setups and antenna solutions.

This page includes an interesting and comprehensive review of the ICOM IC-7300 SDR HF / 50 MHz transceiver. The author focuses on many aspects of this transceiver with impressions based on his experience

Review of the ICOM IC-R9500 Wide Band DSP Receiver

Transmission lines have many uses other than simply transferring RF power from one point to another. Impedance matching, baluns and filters are probable the most common of these.

This page describes a printed circuit board that you may use to build a QRP keyer.

This project involves constructing a dual-band Moxon antenna, optimized for ham radio enthusiasts, with functionality on both the 10-meter and 6-meter bands. The antenna is designed to operate using a single 50-ohm feedpoint, acting as a mini-beam on 28 MHz (10 meters) and as a 2-element Yagi on 50 MHz (6 meters). Performance-wise, it offers a 4.0 dBd gain on 10 meters and 4.3 dBd on 6 meters, with impressive front-to-back ratios of 30 dB and 11 dB, respectively. Builders like Aleks (S54S) and Marcio (PY2OK) have successfully brought this design to life using the provided specifications. Aleks noted that bending the corners of the structure proved especially useful during assembly. The project comes with a detailed parts list, highlighting the use of aluminum tubes with different diameters and lengths to form essential components like the reflectors and radiators. For those looking to fine-tune the antenna, adjustments can be made by altering the length of certain parts that fit into larger tubes. The feeding system is equipped with a balun to accommodate different power levels, making the design versatile enough to handle outputs of either 300 watts or 1 kilowatt.