40m transmitter circuit

Shortened dipole for 10 & 40m bands - 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.

Invisible DX antenna for the low bands - Article by DK5WL describes a multi-band DX antenna for the 160m-40m amateur radio bands with low visibility but great performance for long distance communication.

Dual Band 40m/17m dipole - A center feed dual band dipole for 40 and 17 meters by W5DXP

Vertical Moxon for 40 meters - A vertical half-moxon for the 7 Mhz by F6IRF

Antenna Gain to ERP - A radio's transmitting power can be concentrated along the horizon by use of a GAIN antenna. Although you may still be transmitting with four watts of power, your effective radiated powerwill be greatly increased. This table shows the effects of antenna gain on a transmitter with 4 watts of transmit power.

G8JNJ Broadband HF Vertical Antenna - G8JNJ Broadband HF Vertical Antenna - Requires no tuner - great results from 40m to 10m plus 80m & 6m with reduced performance

The VE3TO Radio Beacon Transmitter - The VE3TO beacon transmitter is a hybrid, consisting of both modern solid state and old vacuum tube technology working on 10132.0 kHz

Malaysian Amateur Radio Transmitters' Society - The malaysian amateur radio transmitters' society (marts) is the national organization for amateur radio (ham) operators in malaysia since 1952.

Triangle ATV Association - The Triangle ATV Association is an organization of hams in the Raleigh-Durham-Chapel Hill NC area who communicate by means of our own personal TV transmitters and receivers.

WebSDR on 20m, 40m and 80m  ^{updated  pop} - On this page you can listen to and control a short-wave receiver located at the amateur radio club ETGD at the University of Twente. In contrast to other web-controlled receivers, this receiver can be tuned by multiple users simultaneously, thanks to the use of Software-Defined Radio

Radio Frequency Beacon Finder - This project is a radio frequency receiver that will help the user the trace the direction and distance of transmitter beacon(s) operating at 433MHz frequency by Cornell Univerity

Repeater and Broadcast Transmitter Database - Searchable database of amateur repeaters and broadcast transmitters. The database covers the fifty U.S. states, the District of Columbia, and the ten Canadian provinces.

IC-746PRO TX Problem - The IC-746PRO is a great rig. But it has a few reliability issues, especially with the earlier-production units. This article addresses four problem areas:. IC151 on the RF Unit. Driver circuit on the PA Unit. HRX-muting circuit on the CTRL Unit. Predriver on the PA Unit.

AP Circuits - Printed circuit board fabrication

5Spice - Analog circuit simulation program for the typical circuit designer. Commercial version for windows

Amplifier for 15 and 17 meter band - The two linear amplifiers are ment for use with QRP SSB/CW/FM/AM transmitters on the amateur bands 15 and 17 meters can be powered from a 12 volt DC supply by ON6MU

Enable Low Cost RF Power Amplifiers - A new paradigm for low cost, reliable RF amplifier ‘pallets’ has been enabled by new circuit design, manufacturing and thermal management techniques

Power Aamps RF voltages - This test circuit is easy to duplicate, and demonstrates the extreme voltages that appear in an amplifier when the load is improper for the amount of drive power applied.

Build a Remote Control Antenna Switch - Remote Control Antenna Switch made with two circuits board

A fool-proof VOX - A circuit which had been used in many other application before. The configuration described here is optimized for IPHONE/radio operation.

N7KSB Milliwatt transmitter - N7KSB used this 1/2 watt CW transmitter, with a roof-mounted ground-plane antenna to work all continents and over 30 countries.

Lightning Protection : Protecting each I/O line - KB22UT Article on how protecting ham radio station and in particular I/O Lines such as AC power, coax cable, control circuits, telephone line.

HV power supplies - WV0NNI 2,800 VDC @ 2 Amps Continuous Variac adjusts filament voltage. A voltage doubler circuit, well suited for smaller, compact linear amplifiers.

80m CW QRP transmitter - 80 metre ceramic resonator VXO CW Transmitter by VK1PK

Sound Card interface - Interface to insulate the radio circuits from the computer by VK2GWK