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AM/FM/CW QRP RF Power Amplifier for the HF 10 or 11 meterband (28MHz/27MHz)

Why Packet Radio? Could be, You are Missing Something Funm, by Greg Jones, WD5IVD

A 3 and 5 element portable yagi antennas for 2 meter band

Dedicated to Yaesu FT847 with mods infos and links... by F1MDT

This project describes an ARDUINO based automatic antenna tuner, for an end-fed half wave (EFHW) antenna, working on 20 & 40 meter bands

RTTY SSTV PSK31 MFSK MT63 PACKET APRS and more...

1500 Watt HF power amplifier

Italian page including pictures schematics diagrams of an home made linear amplifier using four EL509 in parallel. Output power is about 700W.

N6QAB Radio Direction Finding Web Site, DF vehicles, transmitters, sniffers, dopplers, TH-D7A

YU1AW project for a home made QRO PA 144 MHz 20 kW GU36B-1

A 1:4 balun suitable for folded dipole antennas

Use plain water with a little salt added to build your own Dummy Load

These devices are called Traps, but they are actually more like frequency sensitive switches. They are parallel resonant, high Q, tuned circuits which provide a very high impedance at their frequency of resonance.

Calculate your dipole, 3 element yagi and a simple dipole

How repair the traps, and then homebrew the rest of the antenna, including the matching box

VE7CA reprint an interesting article taken from arrl antenna compendium. Two elegant practical and portable 6-meter gain antennas, a two-element quad and a tree-element Yagi antenna for 50 Mhz-6 meter band

The homemade CW paddle key design, inspired by a QRP homepage, utilizes soldered PC board material for its construction. The builder, DL5NEJ, modified an existing design to achieve a smaller footprint, preferring a compact setup for portable operations. This paddle was specifically built to complement a Wilderness Radio SST20 QRP transceiver kit, demonstrating its suitability for low-power operations. The project details suggest a straightforward assembly process, with the primary components being readily available PC board scraps. The design emphasizes simplicity and functionality, aiming to provide a reliable keying experience comparable to commercial paddles like the Bencher. Performance evaluations indicated the simple paddle operates effectively, prompting further exploration into similarly minimalist QRP rig designs. Additional construction details for a similar paddle are available from PA0CMU.

Over 70 international contests are supported by YPlog, a Windows-based logging and radio control program designed for amateur radio operators. This software integrates with various digital mode applications like _WinPSK_, _HamScope_, and _MMTTY_, facilitating partially automated log entry for modes such as PSK31, CW, and RTTY. It provides comprehensive logging capabilities including QSL label printing, beam headings, and dup-checking, alongside award tracking for DXCC, ITU/CQ zones, IOTA, Grid Locators, and Counties. The program offers advanced contesting features, including multi-multi or multi-2 networked operations with automatic log data sharing, multiple Cabrillo submission formats, and configurable CW keyboard layouts. Device support extends to TR-compatible CW keying, SO2R control with Top-Ten devices like the DX-DOUBLER, and internal W9XT digital voice keyer integration. YPlog is notable for its support of the _OK1RR DXCC_ country resolution files, providing a robust historical DX compendium. Beyond logging, YPlog includes two freeware utilities: one for computing design parameters for coaxial traps and another for displaying and printing azimuth and Mercator maps from the operator's QTH. The software runs on Windows 95/98/ME/NT/2K, with a recommended screen resolution of 1024x768. Registration costs **$50.00 US** to unlock all features, including full contesting capabilities and rotator control.

How to obtain a dual voltage without a transformer

by Tony I0JX

A design of a 2 m quagi antenna by TA2IB

The beam has only one feedpoint with 50 Ohm and has an open-sleeve element for 12 m by DK7ZB

HF QRP Linear Amplifier with 2x 2SC2166 + 2x 2SC1969 Push Pull Transistors (13.8V)

5 elements "vee" log-yagi for 10m band- boom lenght : 4mt. Gain : over 10 dBd , f/b =over 40 db (deep null) f/b= min 20dB for different polarization signals

A Parasitic Lindenblad Antenna for 70cm by Anthony Monteiro, AA2TX. This is the official 16 pages PDF File published by AMSAT about the 70cm Parasitic Lindenblad Antenna.

KF4SCI picture of a project for a VHF UHF jpole antenna working on 220 and 440 MHz.

PDF resources containing information on low cost ssb,am,cw circuits, which are useful for beginners.

Coaxial cable loss in db per 100 ft.

A site devoted to Amateur Radio Homebrewing, CW-decoder, CW QRP Transceiver for the 40 & 20 meters band, CMOS reader

VHF Antenna in a lunchbox. The magnetic loop on two metres band Lloyd Butler VK5BR

antennas experiments by David Reid PA3HBB G0BZF

F6DED page of a 2 element beam W8LK antenna with pictures and dimensions, in french

Cross-Yagis for Terrestrial and Satellite Work The 2x6-El.-Cross-Yagi (28 Ohm, 2.60m Boom) by Henk, PA3GUO

Yaesu FT 101 unofficial web site managed by NW2M

The Bazooka-antenna was developed by the staff of M.I.T. for radar use. The original Bazooka used coaxial cable for the entire radiating elements.

Magnetic longwire baluns 1:9 combined with ground, a 1:2 and 1:1 balun connections by ON6MU

SP5DDJ mini antenna tuner for QRP operations

Yaesu CAT Cable for FT-817 857 897

This little gadget is that it allows you to tune up at full peak output power, whilst limiting the average power to a fraction of the peak, thereby protecting the PA from meltdown

MC-50 microphone modification for high emphasis, connecto kenwood ts-50 to kenwood radios.

A vertical monoband that's small, light and portable, needs no counterpoise and performs as well as a home antenna

Easy for calculate formula which could be a wake-up call for you. The SWR value at the input of antenna cable is not a actual SWR of your favorite antenna.

Web site updated several times per month. It covers all aspects of ham radio.

A shorten Dual-Band Dipole with overall length of about 11 m. For this antenna traps are substituted by inductors, in order to cover the 10 & 40 m. Bands.

Freeware program, special and easy to use packet program for communicating with ISS, PCSat and other 'compatible' sats. Can also be used for basic normal packet.

Includes EH antennas, 7Mhz vertical monopoles, 5 elements vee log-yagi for 10m and more

Schematic for a DIY 70 cm vertical antenna

40 meter transmitter by K9GDT

PA2OHH portable regenerative receiver

Gi7b is tube designed for microwaves but working good as HF amplifier. Idea is to build cheap, reliable HF amplifier covering 160 meters band.