Raspberry Pi as an SDR

The Raspberry Pi can be used as a Software Defined Radio (SDR) transmitter with a range of 5 kHz to 1500 MHz, with rpitx software developed by Evariste Courjaud F5OEO.

The antenna is connected directly to a GPIO pin via a suitable filter, and output will be few mW, unless a PA is used. The GPIO output impedance is a lot more than 50 ohms so it will be very inefficient with, say, a dipole antenna, unless the filter is designed to match the GPIO output. Cheapest way to get on the air with it is to use a Pi Zero or Zero 2.

Here is a GitHub page with all the details:

https://github.com/F5OEO/rpitx

Here is an earlier account of how to generate SSB on 40 m and 20 m using an RPi:

https://www.icqpodcast.com/news/2013/5/19/ssb-using-a-raspberry-pi


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