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 transmitter lies a classic two-transistor oscillator-amplifier configuration. The first transistor serves as a crystal-controlled oscillator, providing stable frequency generation, while the second transistor functions as a power amplifier to boost the signal to useful output levels. The circuit’s simplicity is deceptive – every component serves a specific purpose in creating clean, efficient RF output suitable for CW operation.
What makes the Pippin particularly attractive is its low power consumption and compact footprint. Drawing minimal current from a modest power supply, this transmitter can operate for extended periods on battery power, making it perfect for field operations, emergency communications, or quiet portable adventures. The crystal-controlled frequency stability ensures your signal stays precisely where it belongs, while the straightforward construction makes troubleshooting and modifications relatively simple.
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