DIY Antennas, QRP, SDR & Ham Radio Projects from VU3DXR
When you need accurate, stable frequency generation for digital circuits, few solutions are as elegant and cost-effective as a crystal-controlled CMOS oscillator. This classic circuit design demonstrates how a simple TV color crystal can be transformed into a versatile frequency source for various applications. At the heart of this circuit lies an inexpensive 3.58 MHz […]
This simple sine wave oscillator uses a transistor-based phase-shift network to generate a clean periodic signal, then amplifies it with an LM386 for usable output. It runs on a 9V supply and suits audio testing, tone generation, and learning oscillator fundamentals
LM386 Audio oscillator This one is excellent application of widely used audio amplifier IC LM386.Its output is square wave at no load condition. Its frequency is governed by supply voltage. It can be used as code practice oscillator, even as side tone for your qrp radio. The LM386 is an widely abused integrated circuit containing […]
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 […]