DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
QRP amateur radio projects and low-power HF transmitters including CW and AM rigs, crystal oscillators, and portable antennas for efficient communication with ≤5 W power
This pippin QRP transmitter is basically a conventional colpitts type crystal oscillator with output taken from a low value collector load resistor and direct coupling is made into the base of PNP transistor used as an amplifier. This simple circuit develops around one watt output with 12V as power supply. At the heart of this […]
The above 7 Mhz 5 Watts CW Transmitter circuit was found in one of back issues of sprat. Still i am wondering how 5 watts juiced out from this tiny crystal oscillator circuit. This classic 7 MHz CW Transmitter circuit demonstrates how effective amateur radio equipment can be built with minimal components and straightforward design […]
Build a versatile 7MHz QRP Transmitter capable of both CW and AM modulation. This DIY guide features a stable 40-meter crystal oscillator, a class-C power amplifier, and simple switching for dual-mode amateur radio operation.