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Calculate the value of an unknown resistor with this free program for windows

This article is about a simple vertical end-fed-half-wave wire antenna for 10 meters that can be used in case of restricted space.

In this article the author provides some guidelines on how to solve a common problem when stacking different types of yagi antennas on the same mast, limiting the effects on gain and radiation pattern of both antennas

This app will give you a 16 tone DTMF keypad and the ability to generate custom DTMF sequences, and set the duration and tone to silence ratio. Includes the characters 1234567890*# and the menu tones ABCD. You may enter a custom sequence via the keypad, soft keyboard, or speech if your device already has speech-to-text capability. This is basically a touch tone telephone keypad, which may be of interest to amateur ham radio repeater operators

A complete guide to undestand and know how electret condensor microphone elements works by K3DAV

Layman level explanations of "seemingly" mysterious LF MF and HF propagation occurrences.

This sweeper built for a narrow bandwidth filter adjustment, use a simple 555 version sawtooth wave generator.

Six elements yagi antenna for 6 meters band. This antenna design is based on the QuickYagi 4 software by WA7RAI, uses a 6.5 m boom, feature 12.0 dBi gain and 35dB front/back

A transceiver front-end protector in high signal level environments. An homemade RF limiter to protect your receiver front-end from high radio frequency.

QRQ or Copying CW over 70 wpm

VK Contest Log (VKCL) is a free contest log software specialising in Australasian contests but also covering some international ones too. Author is SK, you can donwnload the latest version 4.15.

A guide on manually programming D-Star ID-51A and ID-31A Handheld

Experimenting vertical wire antennas for 40 and 20 meters supported by balloons resulting in excellent gain in RX and good overall performance against horizontal dipole

Homebrewing a Gamma Match to tune yagi antennas

Study of the Coaxial Dipole: Just how does this thing work.

Receive and listen to FM and AM radio broadcasts on your browser or ChromeBook using an RTL2832U-based USB digital TV tuner.

Yaesu FT817 all band, all mode handheld transceiver article.

An Energy Analysis at an Impedance Discontinuity in an RF Transmission Line

This manual is an edited version of the GAP supplied document, complete with diagrams, pictures and assembling notes by Mitch Baum AE2A. This is 29 pages document in PDF Format.

An homebrew audio mixer for the ham shack by GW6ITJ

An home made low pass filter for 70 MHz by IK0VAQ

Want to operate on 40 meters but only have a space a little over 16X16 ? Try this antenna.

An 80m transceiver using just 14 parts plus crystal and earpiece

A simplified Guide to the FT8. Dxpedition mode. By Stefano IK2HKT – Rel. 2.0.0 - January 2019. This document explains how to configure WSJT to work on F/H mode DXPedtions, how to operate and make a call to a dxpedition calling CQ in FT8 Fox Mode.

Slot cubes are folded skeleton slot antennas with widened, folded dipoles bent into a cube to reduce size. QST Article 12 2019

Digital voice on Amateur Radio - devoted to the discussion of digitized voice and data over analog emission modes.

This is a presentation used at OVARC on the LindenBlad antenna construction. The presentation cover several topics about this antenna, from the basic antenna design, to the guide on how to contruct a custom lindenblad antenna for the 2 meters band and and 70 centimenters band.

An home made FETer QRP transceiver for the 80 meters band

There are many designs for building preamps each with their own advantages and disvantages. In this PDF Article author reviews several different types.

Free Android app that tracks and alerts on ISS passes with specified criteria.

Article from 73 Amateur Radio Today about experimenting on ferrite loops transmitting loop antennas for 80 and 160 meters bands.

Design and build a 6 meter 2-element Moxon antenna mostly from available aluminum tubing and angle stock.

About Coax Traps, NC4FB examine the operation of coax traps through modeling.

Hone your Morse code skills with this entry-level project. Article includes the full schematic of the CW Trainer, describes the sketch and how to operate the morse code trainer.

How to run an SDR Receiver on the Android Google Nexus 7 using SDR Touch App and an RTL-SDR dongle, review and costs by IW5EDI

This document is a must read for anyone considering building a good low cost HF multi-band antenna system. The author combine in this document four important ingredients to produce simple but effective antenna system, like antennas of non resonant length, line attenuation, the transmatch and the balun

A 160W linear amplifier for 4 meters band based on GI0GDP

The author who works successfully via EME on this band wants to describe his own yagi design and give some of hints for the construction. by Heinrich F. Reckemeyer, DJ9YW

Cushcraft XM240 transformation into a Moxon antenna by W6NL

Have you ever thought of setting up a portable HF station for an activity ?

Introduction to WSPR beacons. Article describe WSPR2 and WSPR15 beaconing mode and include a frequency reference table for both WSPR modes

Adding 17 meter band to Mosley TA-33M yagi antenna

This is a schematic drawing of a project for the construction of a portable mast that can easily be made with PVC pipes.

Iambic Keying, Debunking the Myth by Marshall G. Emm, N1FN. A keying system controls transmitter activation, ranging from basic switches to electronic keyers that generate Morse code based on paddle input. Iambic keyers, introduced in the late 1950s, respond to simultaneous paddle closures with alternating dots and dashes. Despite touted efficiency, actual benefits are modest, offering about a 5% improvement in keystrokes, diminishing at higher speeds. Iambic keying's practical value is limited and may restrict sending speeds.

Technical supplement manual of the Yaesu FT-8800R in english

This is a QST Article published in January 1982 by W1FB D. Demaw and HH Beverage and is a complete review of the original article published in 1922, which updates and reivew the beverage antenna theory and developlment, explaining the antenna design of transformers and gives accurate reports on antenna general performance.

How can the current "flowing" out of the top of a mobile loading coil be greater than the current "flowing" into the bottom of the coil?

PDF manual of the TW4040 The Adventurer MonobanderTM TransWorld Antennas

APRS-Webserver, that presents aprs-data and maps for free using Google Maps api. The position data is imported from aprs.org, winlink.org and echolink.org. The map data are partially commercial and free. This server is for amateur radio purposes only.

Manual of the BD-35 Dual Band VHF UHF RF power amplifier by Mirage Amp