WSPR,SSTV and Rf signal generator for Raspberry, a Raspbery Pi Breakout board (KIT)
This kit provides a breakout board to use the Raspberry Pi clock generator as an RF source or simple amateur radio transmitter.
The Raspberry Pi has a built-in clock generator, a powerful frequency synthesiser which can generate frequencies up to 250MHz. This is enough to provide a useful RF signal source for experimentation, or given suitable filtering and antennas to allow the Pi to be used as a low-power amateur radio transmitter.
On the board you'll find the clock generator and some of the the SPI/GPIO lines brought out to headers, with a BNC socket for RF output and a small prototyping space with three ground rails. A DC blocking capacitor is supplied allowing the construction of a basic square wave source, while the prototyping area may be used for the construction of low pass filters, transmitter control logic, or other circuitry.
For best results I would recommend adding a Low pass filter to help with reduction of the second harmonic and making the Square wave a sine wave.