# Freq Show: Raspberry Pi RTL-SDR Scanner ## Overview ![](https://cdn-learn.adafruit.com/assets/assets/000/112/555/medium800/wireless_freqshow-banner.jpg?1655924868) Have you ever wondered what's in the radio waves zipping invisibly around you every day?  [Software-defined radio (SDR)](http://en.wikipedia.org/wiki/Software-defined_radio) is a great tool to explore radio signals using a computer and inexpensive radio tuner. With SDR you can examine many radio signals such as [FM radio](http://en.wikipedia.org/wiki/FM_broadcasting), [television](http://en.wikipedia.org/wiki/Digital_television), [emergency & weather radio](http://en.wikipedia.org/wiki/Weather_radio), [citizen band (CB)](http://en.wikipedia.org/wiki/Citizens_band_radio), wireless protocols and [much more](http://en.wikipedia.org/wiki/Radio_spectrum). Although dedicated SDR hardware like the [HackRF](https://greatscottgadgets.com/hackrf/) allow you to tune an immense range of the radio spectrum, you can easily get started with SDR using a Raspberry Pi and [inexpensive RTL-SDR tuner](https://www.adafruit.com/product/1497).  Inspired by the [HackRF PortaPack](http://hackaday.com/2014/08/17/defcon-22-the-hackrf-portapack/), this project will show you how to build a small portable SDR scanner using a Raspberry Pi, [PiTFT](https://www.adafruit.com/product/2097), and [RTL-SDR](https://www.adafruit.com/product/1497) radio dongle.  With the Raspberry Pi Freq Show RTL-SDR scanner you can visualize the invisible world of radio! **UNDERSTAND: FREQSHOW _DOES NOT PLAY AUDIO._ ** It graphs the _frequency_ and _amplitude_ of RF signals, which can be useful for troubleshooting and developing a basic understanding of radio and wireless protocols, but it does not _decode_ nor _demodulate_ them. Before you get started it will help to familiarize yourself with a few other guides for more background information: - [Circuit Playground: F Is For Frequency](../../../../circuit-playground-f-is-for-frequency/) - [Getting Started With RTL-SDR and SDR#](../../../../getting-started-with-rtl-sdr-and-sdr-sharp/overview) - [FFT: Fun with Fourier Transforms](../../../../fft-fun-with-fourier-transforms) - [PiTFT 3.5" Touch Screen For Raspberry Pi](../../../../adafruit-pitft-3-dot-5-touch-screen-for-raspberry-pi/overview) - [Raspberry Pi: Using SSH](../../../../adafruits-raspberry-pi-lesson-6-using-ssh/overview) Also for some inspiration on what you can do with SDR, check out these excellent presentations from previous [DEF CON conferences](https://www.defcon.org/): - [All Your RFz Are Belong To Me: Hacking The Wireless World With Software-Defined Radio](https://www.youtube.com/watch?v=ZuNOD3XWp4A) - [Noise Floor: Exploring Unintentional Radio Emissions](https://www.youtube.com/watch?v=5N1C3WB8c0o) - [Hacker + Airplane = No Good Can Come Of This](https://www.youtube.com/watch?v=mY2uiLfXmaI) Info: - [Next Page](https://learn.adafruit.com/freq-show-raspberry-pi-rtl-sdr-scanner/hardware.md) ## Featured Products ### Software Defined Radio Receiver USB Stick - RTL2832 w/FC0013 [Software Defined Radio Receiver USB Stick - RTL2832 w/FC0013](https://www.adafruit.com/product/1497) If you've ever been curious about software defined radio (SDR), this USB stick is the easiest way possible to have fun with a powerful, configurable receiver. Packed with the powerful RTL2832U and FC0013 tuner, it can tune into signals from 48.25 - 863.25MHz. That means you can use a... In Stock [Buy Now](https://www.adafruit.com/product/1497) [Related Guides to the Product](https://learn.adafruit.com/products/1497/guides) ### PiTFT - Assembled 480x320 3.5" TFT+Touchscreen for Raspberry Pi [PiTFT - Assembled 480x320 3.5" TFT+Touchscreen for Raspberry Pi](https://www.adafruit.com/product/2097) Is this not the cutest, little display for the Raspberry Pi? It features a **3.5" display with 480x320** 16-bit color pixels and a resistive touch overlay so is slightly larger than [our popular original](https://www.adafruit.com/product/1601). The plate uses the... Out of Stock [Buy Now](https://www.adafruit.com/product/2097) [Related Guides to the Product](https://learn.adafruit.com/products/2097/guides) ### Raspberry Pi Model B+ 512MB RAM [Raspberry Pi Model B+ 512MB RAM](https://www.adafruit.com/product/1914) OMG OMG OMG, did you hear? There's a Raspberry Pi called the Model B+ and check it out...more USB ports, more GPIO, better power supply, four mounting holes, less sticky-out SD card! Yep, that's right, the fantastic engineers at Raspberry Pi HQ have blessed us with a new design.... In Stock [Buy Now](https://www.adafruit.com/product/1914) [Related Guides to the Product](https://learn.adafruit.com/products/1914/guides) ### Raspberry Pi Model B 512MB RAM [Raspberry Pi Model B 512MB RAM](https://www.adafruit.com/product/998) Adafruit ships the **Raspberry Pi Model B 512MB RAM** as of 10/18/2012. The Raspberry Pi® is a single-board computer developed in the UK by the Raspberry Pi Foundation with the intention of stimulating the teaching of basic computer science in schools. The Raspberry... No Longer Stocked [Buy Now](https://www.adafruit.com/product/998) [Related Guides to the Product](https://learn.adafruit.com/products/998/guides) ### MCX Jack to BNC RF Cable Adapter [MCX Jack to BNC RF Cable Adapter](https://www.adafruit.com/product/1531) This RF adapter bit is great for anyone doing RF work. If your receiver/transmitter/transceiver has an MCX connector but you really want to tie it to a BNC antenna, this dongle will do the trick! In Stock [Buy Now](https://www.adafruit.com/product/1531) [Related Guides to the Product](https://learn.adafruit.com/products/1531/guides) ### MCX Jack to SMA RF Cable Adapter [MCX Jack to SMA RF Cable Adapter](https://www.adafruit.com/product/1532) This RF adapter bit is great for anyone doing RF work. If your receiver/transmitter/transceiver has an MCX connector but you really want to tie it to an SMA antenna, this dongle will do the trick! In Stock [Buy Now](https://www.adafruit.com/product/1532) [Related Guides to the Product](https://learn.adafruit.com/products/1532/guides) ### PowerBoost 500 Charger - Rechargeable 5V Lipo USB Boost @ 500mA+ [PowerBoost 500 Charger - Rechargeable 5V Lipo USB Boost @ 500mA+](https://www.adafruit.com/product/1944) PowerBoost 500C is the perfect power supply for your portable project! With a built-in battery charger circuit, you'll be able to keep your project running even while recharging the battery! This little DC/DC boost converter module can be powered by any 3.7V LiIon/LiPoly battery, and... Out of Stock [Buy Now](https://www.adafruit.com/product/1944) [Related Guides to the Product](https://learn.adafruit.com/products/1944/guides) ### Lithium Ion Polymer Battery - 3.7v 2500mAh [Lithium Ion Polymer Battery - 3.7v 2500mAh](https://www.adafruit.com/product/328) Lithium-ion polymer (also known as 'lipo' or 'lipoly') batteries are thin, light, and powerful. The output ranges from 4.2V when completely charged to 3.7V. This battery has a capacity of **2500mAh** for a total of about 10 Wh. If you need a smaller battery, In Stock [Buy Now](https://www.adafruit.com/product/328) [Related Guides to the Product](https://learn.adafruit.com/products/328/guides) ## Related Guides - [AstroPrint 3D Printing](https://learn.adafruit.com/astroprint-3d-printing.md) - [Touch Pi: Portable Raspberry Pi](https://learn.adafruit.com/touch-pi-portable-raspberry-pi.md) - [Portable Apple Watch Charger](https://learn.adafruit.com/portable-apple-watch-charger.md) - [Printy Boost: Reimagining a Classic Adafruit Kit](https://learn.adafruit.com/printy-boost-reimagining-a-classic-adafruit-kit.md) - [CYBERDECK Expansion Plate](https://learn.adafruit.com/cyberdeck-plate.md) - [RasPipe: A Raspberry Pi Pipeline Viewer, Part 2](https://learn.adafruit.com/raspipe-a-raspberry-pi-pipeline-viewer-part-2.md) - [apt.adafruit.com](https://learn.adafruit.com/apt-adafruit-com.md) - [Energy Budgets](https://learn.adafruit.com/energy-budgets.md) - [Collin's Lab: Solar](https://learn.adafruit.com/collins-lab-solar.md) - [Super Game Pi](https://learn.adafruit.com/super-game-pi.md) - [Trinket NeoPixel LED Longboard](https://learn.adafruit.com/trinket-neopixel-led-longboard.md) - [Kali Linux on the Raspberry Pi with the PiTFT](https://learn.adafruit.com/kali-linux-on-the-raspberry-pi-with-the-pitft.md) - [DIY Pocket LED Gamer - Tiny Tetris!](https://learn.adafruit.com/diy-3d-printed-handheld-pocket-game-tiny-tetris-snake.md) - [Mystery Box: NeoMatrix Mk I](https://learn.adafruit.com/mystery-box-neomatrix-mk-i.md) - [Booster Cable](https://learn.adafruit.com/booster-cable.md)