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British Columbia Frequency Modulation Communications Association

The American, Continental, and International Morse Codes

Universal Postal Union, International reply coupon page

History of all OSCAR satellites from 1961 till today in chronological order.

Operating NVIS mode, understanding operation frequencies, choosing the proper antenna to operate with the Near Vertical Incidence Skywave propagation

There are some aspects in regards to mailing QSL letters to Russia which you should know

Installation and assembly instructions for the multiband HF vertical Antenna by GAP

This calculator ask as input diameter, lenght turn and frequencu and will return L and Q

This project is a USB Audio, Serial and PTT interface for rigs that does not directly support digital modes provided by applications such as FLDIGI, WSJT-X and JS8CALL. Plug these interface devices into your Windows or Linux laptop or Raspbian Raspberry Pi and you can send and receive digital tones to/from your rig and automate the frequency and mode control and PTT control.

A collection of projects and equiment home made for 24 GHz operations

Tips and tricks for succesful soldering. An illustrated guide for beguinners and an usefull reminder for expert in soldering.

New PA stage for good old Atlas 350XL HF transceiver

This circuit stores a morse code message as bits in an EPROM chip, the message controls a relay that keys a CW morse code transmitter. An Arduino processor can also be used in place of this circuit, that eliminates the need to build the circuit and program an EPROM.

Weak Signal Audio 160m, choosing a headphone for weak signals reception

A tutorial on how to setup a receiver capable to decode SSTV signals with a small RaspberryPi version 2 and a RTL-SDR dongle. The author explains how to install the needed software to interface the RTL-SDR and a step by step guide to install the QSSTV software used to decode the signals.

G3CWI contest software reviews, compare NA SD TR CT and WriteLog

A Tower Project at WOIVJ. A pictorial story of the erection of a 40 foot, self-supporting, fold-over tower.

Assembling the Small Wonder Labs SW+40 QRP Transceiver Kit documented by K4ICY

Digital modes contest rules by TARA. Offers the All Seasons contest Tournament. A new concept in contesting.

Demonstrates the construction of a high-power 6-meter (50 MHz) amplifier, specifically designed for demanding modes like EME, TEP, and multiskip Es. It details the use of a _GU-43B_ tetrode in a grounded-cathode configuration, emphasizing the need for stabilized grid voltage and input capacitance compensation. The resource provides a comprehensive schematic, power supply design, and practical considerations for component sourcing, particularly for high-voltage and high-current sections. The builder achieved an output power of **1250 watts** with an anode current of 0.65 amperes and 3200 volts anode voltage. The article also covers the physical construction within a modified P6-31 enclosure, outlining the internal layout for RF and power supply sections, and includes photos of the completed unit. It highlights critical safety precautions for working with high voltages and reactive currents up to **20 Amperes** in the P-network.

Award series "Castles of Poland" are issued for two-way QSO or SWL-report with radiostations working from castles being on territoy of Poland.

An online multiple calculator of 16 impedance matching networks

Tuned circuits for Progressive Receivers

Alpha 87a Communication can be used either stand alone to control the Alpha 87a amplifier or together with several CAT-Control programs by HB9ZS

An inexpensive spectrum analyzer for the radio amateur, with a respectable performance and a quite good dynamic range. Schematic and basic information on how spectrum analyzers works.

BPQ32 allows a computer running under Microsoft Windows to act as a Node in a NET/ROM compatible AX25 network, and to support a multiuser Mailbox, or other similar applications.

How to convert the ICOM VHD base station IC-275D to 275H 100W 144-148Mhz

Dutch Amateur Radio DX & Contest Group

A Neat Little Tool For The Bench. The basic information needed when testing a multi-conductor cable like CAT-5 is that each wire in the 4 pair cable goes to the correct pin in the RJ-45 plug and that all crimps are solid.

This simple antenna was installed on the attic. Antenna was matched with help an Automatic ATU in 40, 30, 20, 17, 15, 12 and 10 meter amateur Bands. The Antenna worked satisfactory on the above mentioned bands.

Learn Morse Online in 40 lessons with this web based morse code learning program, based on the Koch method. Choose the lesson, adjust the wanted parameters, and start the transmission of a set of random characters based on chosen lesson. Recognize the code and verify it at the end of the lesson.

The equipment shown on this page comprises a basic G3WDG transmit and receive system with the addition of a 1W Qualcomm amplifier.

LA3ZA Unofficial Guide to Elecraft K2 Modifications

WSJT-X is an experimental version of WSJT implementing JT9, a mode designed for making QSOs under extreme weak-signal conditions

The contest takes place the first full weekend of May (from 1800Z on Saturday May 5 to 0400Z Sunday May 6, and from 1100Z to 2100Z Sunday May 6). A total of 20 hours contesting!

Article based on ROHN engineering specification that will guide on proper guying heights and guy lengths when guying ham radio antenna masts. It will help you determine ahead of time the proper length of guy wires and the distance from the base of the mast to the anchor points

The TVI filters described in this page worked very well in curing a TVI problem on 2m abd 70cm

This generator requires 100volts supply at 5mA. A 0 -5 mA meter inserted at J1 measures the crystal current.

OH3TR operates the OH3SHF microwave beacons on 2.3, 3.4, 5.7, 10 and 24 GHz

My LoTW is a free viewer app for Logbook of the World by ARRL. Features include, View all the QSOs you have submitted to LoTW, Add multiple callsigns under your LoTW account, View all your QSLs, Share digital QSL image which is created by the app for QSLs. Either save it on your device or share it on facebook, View statistics for your worked stations/DXCC/bands etc

Sending QSL via mail, from the ARRL Club Newsletter

PSK Reporter provides a real-time visualization of amateur radio digital mode reception reports, aggregating data from a global network of monitoring stations. This platform is particularly useful for operators utilizing modes such as FT8, FT4, and PSK, allowing them to observe signal propagation paths and assess their station's reach. The interactive maps display reception reports, enabling hams to analyze band conditions and optimize antenna performance for various frequencies and times of day, aiding in understanding ionospheric conditions. Operators can filter reports by callsign, band, mode, and time, gaining insights into specific propagation events or evaluating the effectiveness of their transmit setup. The data collected helps in predicting optimal operating windows for DX contacts across various digital modes. Philip Gladstone is the contact person for comments and discussions regarding the system.

This page contains Contributions to a Discussion on the Moon-Net about the Application of Digital Signal Processing (DSP) Methods in Moonbounce.

Selecting capacitors in RF power applications at HF by I0JX

Testing a linear regulated power supply using headlight bulbs for loading.

Constructing a basic multimeter involves integrating a 0-1mA meter movement with various shunts and multipliers, selected via a switch, to create a versatile instrument capable of measuring DC volts, current, and resistance. The design outlines two main units: a primary unit handling six DC current ranges up to 1 amp and eight DC voltage ranges up to 1000 volts, alongside an internal battery for an ohms range up to 200,000 ohms. This approach allows for a practical, hands-on understanding of meter operation. An add-on unit further extends the multimeter's capabilities, incorporating a meter rectifier and switched series resistors to provide four AC voltage ranges up to 100 volts. Additional shunt and series resistors, designated Ra and Rb, are included to expand the instrument's range to 10A and 5kV, demonstrating how modular design can enhance functionality. When this add-on is in use, the main instrument is set to measure 1mA FSD, connecting via specific lugs. Component selection emphasizes precision, with 1% tolerance high stability resistors for series elements and Eureka resistance wire for shunts. The design specifies values calculated for a meter with 60 ohms internal resistance, noting that these would require modification for different meter characteristics. Experimental adjustment of shunt values is recommended to ensure accurate readings against a calibrated reference meter, reinforcing practical calibration techniques.

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This DIY vertical multi-band Windom antenna offers a practical and effective solution for amateur radio enthusiasts seeking a versatile and compact antenna for HF communications. Its simplicity of construction, multi-band capability, and favorable performance make it a valuable addition to any radio shack. The article provides detailed instructions on constructing the antenna and balun, along with diagrams and component specifications. Field tests demonstrated successful contacts with stations across Europe and North America on 14, 18, and 28 MHz. The antenna exhibited comparable performance to a W3DZZ dipole and outperformed a Cobweb antenna on 18 MHz. Low noise levels were observed, effectively suppressing background noise.

A very simple experimental short wave radio receiver. This is basically just a crystal radio with two stages of transistor amplification afterwards made with scrap components.