# Circuit Playground: N is for Noise ## Video https://youtu.be/_zYT66uEMIQ You can't see it or hear it, but it sure can effect your electronics! Adabot and Minerva set out to solve the mystery of electrical noise … and maybe even watch a movie together. # Circuit Playground: N is for Noise ## Transcription ![](https://cdn-learn.adafruit.com/assets/assets/000/055/087/medium800/circuit_playground_N_is_for_Noise_1.jpg?1528257384) Adabot: Hello Minerva - do you read me? Over. Minerva: Hello Ada [static] It’s difficult to hear [static] ![](https://cdn-learn.adafruit.com/assets/assets/000/055/088/medium800/circuit_playground_N_is_for_Noise_2.jpg?1528257408) Adabot: Hello Minerva [static] - your signal is unclear please re-[static] , over. Minerva: I can’t quite hear you Adabot.  There’s too much noise! ![](https://cdn-learn.adafruit.com/assets/assets/000/055/089/medium800/circuit_playground_N_is_for_Noise_3.jpg?1528257451) Minerva: Sorry Adabot - there’s too much noise in the signal.  I couldn’t hear you :( Adabot: I know - I couldn’t hear you either. Adabot: Plus - I was going to watch a movie, but it won’t play. Any idea why? ![](https://cdn-learn.adafruit.com/assets/assets/000/055/090/medium800/circuit_playground_N_is_for_Noise_8.jpg?1528257485) Minerva: Something around here might be creating noise and interfering with the wifi signal. Adabot: Noise? I don’t hear any noise. ![](https://cdn-learn.adafruit.com/assets/assets/000/055/091/medium800/circuit_playground_N_is_for_Noise_5.jpg?1528257523) Minerva: Well, Adabot - sometimes there’s noise that we can’t hear. It’s not audio noise, it’s _electrical noise_ and it can cause problems for wireless circuits like your laptop’s wifi … Minerva: … or even our walkie talkies. ![](https://cdn-learn.adafruit.com/assets/assets/000/055/092/medium800/circuit_playground_N_is_for_Noise_6.jpg?1528257557) Adabot: Noise you can’t hear? Interesting. Where could it be coming from? Minerva: Lots of things can create electrical noise, but the most common are device with motors in them.. Minerva: like say … this fan! ![](https://cdn-learn.adafruit.com/assets/assets/000/055/093/medium800/circuit_playground_N_is_for_Noise_7.jpg?1528257575) Adabot: Hmm - but the video still isn’t loading. Minerva: Or … devices that use a lot of power and send out radio waves … or microwaves, did I just hear the microwave oven? Adabot: Oh good - my popcorn’s done! ![](https://cdn-learn.adafruit.com/assets/assets/000/055/094/medium800/circuit_playground_N_is_for_Noise_10.jpg?1528257637) Minerva: And look - now that the microwave stopped, the video is loading just fine :) Adabot: Excellent - we are now noise free! ![](https://cdn-learn.adafruit.com/assets/assets/000/055/095/medium800/circuit_playground_N_is_for_Noise_11.jpg?1528257667) Adabot: But why does electrical noise cause problems like that? Minerva: Too much electrical noise can confuse or overwhelm a circuit. Engineers often have to work on reducing electrical noise in their circuitry because less electrical noise makes a circuit work better. Adabot: Oh - just like how it’s hard for someone to do work when there’s lots of regular noise around. ![](https://cdn-learn.adafruit.com/assets/assets/000/055/096/medium800/circuit_playground_N_is_for_Noise_13.jpg?1528257692) Minerva: Exactly! OK - now that the wifi is working, let’s try the Walkie Talkies again. AdaBot: OK! ![](https://cdn-learn.adafruit.com/assets/assets/000/055/097/medium800/circuit_playground_N_is_for_Noise_14.jpg?1528257730) Adabot: Hello Minerva Can you read me? Over. Minerva: Loud and clear! So what was it you wanted to ask me? Adabot: Oh right! Would you like to come over here and watch a movie with me? Minerva: ... ![](https://cdn-learn.adafruit.com/assets/assets/000/055/098/medium800/circuit_playground_N_is_for_Noise_17.jpg?1528257853) # Circuit Playground: N is for Noise ## Learn More # What is Electrical Noise? ![](https://cdn-learn.adafruit.com/assets/assets/000/055/101/medium800/circuit_playground_noise-waveform.jpg?1528258855) > In electronics, noise is an unwanted disturbance in an electrical signal. Noise generated by electronic devices varies greatly as it is produced by several different effects. > > In communication systems, noise is an error or undesired random disturbance of a useful information signal. The noise is a summation of unwanted or disturbing energy from natural and sometimes man-made sources. > > - via [wikipedia](https://en.wikipedia.org/wiki/Noise_(electronics)) # What creates electrical noise? ![](https://cdn-learn.adafruit.com/assets/assets/000/055/102/medium800/circuit_playground_lightning.jpg?1528259554) Lots of things can generate electrical noise.  Some common sources are: - DC Motors - Fluorescent Lighting - Radio Equipment (including WiFi & Bluetooth) - Lightning - Microwaves - Power Lines - Welding Equipment # How can you stop electrical noise? ![](https://cdn-learn.adafruit.com/assets/assets/000/055/103/medium800/circuit_playground_shielding.jpg?1528260644) Electrical noise can be kept out of a circuit by using conductive shielding which is connected to ground. This electromagnetic shielding can absorb electrical noise and prevent it from escaping or entering a circuit. When a digital or audio cable breaks or wears out, you can usually see the shielding show through the cable's outer layer. ![](https://cdn-learn.adafruit.com/assets/assets/000/055/105/medium800/circuit_playground_cages.jpg?1528261337) Electromagnetic shielding can also take the form of metal enclosures or 'cages' mounted directly on a device's circuit board as seen above. [Learn more about Electromagnetic Shielding.](https://en.wikipedia.org/wiki/Electromagnetic_shielding) # More info Learn more about electrical noise by checking out these links: - [Common sources of interference](https://www.rfvenue.com/blog/2014/12/14/common-sources-of-interference) - [Electrical noise and mitigation](https://www.eetimes.com/document.asp?doc_id=1274125) - [Noise (electronics)](https://en.wikipedia.org/wiki/Noise_(electronics)) - [Electrical noise can come from anywhere](https://www.analogictips.com/electrical-noise-can-come-from-anywhere/) photo by Pavel.skrbek, CC-BY-SA-3.0 ## Related Guides - [Introducing Adafruit Crickit #MakeRobotFriend](https://learn.adafruit.com/adafruit-crickit-creative-robotic-interactive-construction-kit.md) - [Circuit Playground - O is for Ohm](https://learn.adafruit.com/circuit-playground-o-is-for-ohm.md) - [Pearl's Gem Weapon – Steven Universe](https://learn.adafruit.com/pearl-s-spear-steven-universe.md) - [Getting Started With Steven Universe](https://learn.adafruit.com/getting-started-with-steven-universe.md) - [Spinning Logo](https://learn.adafruit.com/spinning-logo.md) - [Micro USB Dock for Circuit Playground](https://learn.adafruit.com/micro-usb-dock-for-circuit-playground.md) - [Makey Paper Craft ](https://learn.adafruit.com/makey-paper-craft.md) - [BOSEbuild Reactive Sound ](https://learn.adafruit.com/bosebuild-reactive-sound.md) - [3D Printed Adabot Figurine](https://learn.adafruit.com/3d-printed-adabot-figurine.md) - [DIY Circuit Playground Shields](https://learn.adafruit.com/circuit-playground-shields.md) - [Circuit Playground Bluefruit Automatic Bike Brake Light](https://learn.adafruit.com/circuit-playground-bluefruit-brake-light.md) - [Circuit Playground TFT Gizmo Snow Globe](https://learn.adafruit.com/circuit-playground-tft-gizmo-snow-globe.md) - [Adafruit Circuit Playground Tri-Color E-Ink Gizmo](https://learn.adafruit.com/adafruit-circuit-playground-tri-color-e-ink-gizmo.md) - [Capacitive Touch Pulsing Heart](https://learn.adafruit.com/3d-printed-heart-capacitive-touch.md)