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This antenna is reported as being lower noise than conventional yagis and had a very low SWR for 500 KHz.

July 2013 DXpedition to Miquelon Op - Eric KV1J

Coax Velocity Factor in Baluns, Does it Matter? Test results show coaxial cable velocity factor does not always enter into stub length calculations especially in the world of Baluns

There are several ways to reduce the length of a dipole and still use it as an effective antenna. Remember it is the electrical length that determines resonance. The physical length can be considerably less than a half wave length on your desired frequency as determined by 468/f MHz.

This is an explanation of the intended way to use TR LOG with two radios in the ARRL November Sweepestakes, CW. The concepts and techniques presented here can work for you in other contests, as most of the ideas are the same.

A simplified operating guide for the Yaesu FT-817

A mircovert antenna assembled for the 40m version of the DL7PE antenna. A one meter long aluminum tube with 24mm diameter is used for the base (element 1) and a 50cm aluminum tube with 20mm diameter for element 2 (the extention). A pvc pipe, 34cm long and with a diameter of 38mm, is used to wind the coil on (1mm enamelled copper wire).

2 Wavelength ,2 Meter Bi-Square Beam , 5dbd gain. This antennas are very cheeap to build and their radiation pattern is similar to a figure 8 with maximum signal through the loop but they may be used as a near-omnidirectional antenna

This 160 meter Delta Loop antenna is made of Hard drawn copper wire AWG 10, the two upper side are 148.5 foot each base wire is 240.9 foot, the feed point at 30.69 foot to one corner, feed with 450 Homs balanced line to an antenna tuner on the ground, then with 50 homs coax to the shack.

Nigel G3TXF plans to operate as ZD7XF on CW from St Helena between 22 June and 30 June.

The PAC-12 Antenna, a multi-band portable vertical, is meticulously detailed in this construction article by James Bennett, _KA5DVS_. The design emphasizes ease of homebrewing using readily available components from local hardware stores, including replaceable loading coils. It outlines the preparation of the 72-inch telescoping whip (originally from Radio Shack, with an alternate source now provided by _Pacific Antenna_), the construction of the loading coils from PVC risers, and the fabrication of the aluminum rod base sections. Specific instructions cover threading aluminum rod with a _1/4-20 threading die_ and assembling the feedpoint insulator with a BNC connector, along with recommendations for radial deployment. KA5DVS, an avid traveler and QRP enthusiast, developed the PAC-12 to address the bulkiness of random wire setups and the limitations of commercial portable antennas like the Outbacker or SuperAntennas MP1. His goal was a lightweight, packable antenna that disassembles into 12-inch sections, achieving an assembled length of approximately 8 feet. The design strategically places the loading coil away from the base for improved efficiency. The PAC-12 notably placed first in efficiency compared to a quarter-wavelength wire vertical at the HFPack antenna shootout during the Pacificon conference in October 2001, demonstrating its practical performance for field operations. Appendix C showcases various _NJQRP Club_ members' PAC-12 constructions, including a 20m beam made with multiple PAC-12 elements.

Hy-Gain TH3jr Tri-band HF 3 Element Beam Covers 10, 15 and 20 Meters assembly instruction manual

A home made, dirty and quick moxon antenna for 144 MHz made with PVC pipes.

A Western Pennsylvania Radio Guide

A review with early observations and technical data specifications of the Icom IC-703 QRP HF+50 MHz transceiver

The Meteor-M N2 is a polar orbiting Russian weather satellite that was launched on July 8, 2014. Its main missions are weather forecasting, climate change monitoring, sea water monitoring/forecasting and space weather analysis/prediction. Meteor-M N2 transmits images using the digital LRPT protocol at around 137.1 MHz with can be received with an RTL-SDR.

3C0W DXCC Annobon, IOTA AF-039 March 10-24, 2018 DX Pedition

Remote Orbitron enables either direct connection between a computer and the shack unit using a serial port OR remote operation from the internet using a WIZ110SR serial to ethernet board.

A log utility for WSJT-X and JTDX Provides functionality missing from WSJT-X and JTDX and more

Aircraft scatter is easily seen on the spectrogram window of digital communication apps, when you know what to look for. Examples of real aircraft scatter usage on six meters band

July 2012 DXpedition to Miquelon Op - Eric KV1J

An interesting article that compares tube amplifiers versus transistor amplifier.

Free programming software for the Wouxun KG-UV6D and KG-UV6X.

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

A spectrum analyzer is always an usefull amateur radio test equipment that should be present in a radio shack. Hams can use it for testing frequency response of filters, amplifiers, and other two-port RF devices. This article illustrate a tracking generator compatible with any spectrum analyzer in the Tektronix 490- and 2750-series lineups

Repairing a KAM interface changing two capacitors and transistors by IK5PWC

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.

The title may seem a strange question. Still, it is often said that the part where the current is largest, radiates most. And from that a rule of thumb follows, saying that if you don't have enough space to hang a complete half-wave wire dipole then try to make the central part hang as freely as possible.

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

The PCB can produce a High Frequency RF signal in the range of 1MHz to 12.5MHz using an AD9833 Direct Digital Sequence (DDS) frequency synthesizer. The signal can be modulated with different Weak Signal modes such as WSPR, JT9 and JT65 using our Arduino 5V/16MHz Pro Micro software.

A learning aid for prospective amateurs and administrative tool for accredited examiners.

The longest element has a total length of 14m and has a boom length of 5.5 meters featuring a total bandwith of 166 kHz

This online web application allows you to train the decoding of Morse code by copying random QSO sentences that can be looped or even mixed.

Specification of the ICOM IC R7100, VHF UHF Receiver

Orca DX and Contest Club BCQP

These baluns are used to attenuate the common mode current that flows on the outside of the coaxial feed line.

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

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

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

KA4RRU/B Ten Meter Beacon

Operating marine mobile with antennas for 15-17-20 meters band.

Construction of an antenna for experimental satellite communication, 8el. (435 Mhz) x 4el. (145 Mhz) Satellite Yagi crossed. No difficulty to built this antenna. Except the gamma match. that requires a little more attention

This antenna looks like an inverted L antenna, yet it is not, it could also be viewed as a 160m off-center fed dipole antenna, it looks more like an end-fed 1/4 wave 160 meter antenna.

DXPSK and SMARTPSK are freeware Windows PSK31 software tools capable to send and recive even multiple tracks of PSK31 signals. SMARTPSK is the improved version of DXPSK capable to display up to 25 tracks.

DXSPOTS is a Telnet connection program. It allows radio amateurs with a lot of DX traffic to know instantly the status of the bands and to know which DX are currently on the air. Following the Packet-Clusters where data was transmitted on VHF/UHF via dedicated relays and sometimes on HF at a very low speed (300Bds on HF), the Internet has taken over and is now transmitting DX information via the computers in most shacks. Translated with www.DeepL.com/Translator (free version)

This article is designed as an introduction to some of the more popular digital modes. From HSCW to FT8 and interesting article with detailed information on popular and historical amateur radio digital modes.

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.

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 project is a python program used to plot the location of QSOs (radio contacts) on Google Earth or other mapping applications. It reads an ADI file of the QSOs and creates a KML file

Analysis, design and construction of a simple & useful SWR meter from yesteryear! Schematic diagram, pictures and instructions to build a Monimatch style SWR Meter