ECE 110/120 Honors Lab Section : Musical Tesla Coil with Microphone Input

Statement of Purpose

We will create a musical tesla coil that can act as a speaker. The tesla coil will take in two different inputs, audio input from an audio source such as a phone, and microphone playback from an Arduino.

Goals: Creating a working Musical Tesla Coil, Microcontroller that can output musical frequencies, Microphone input, ‘AND’ gate failsafe.

Background Research

We will heavily reference a video from Keystone Science video [2] to create our own tesla coil, however we will be creating our own program and circuitry to give the tesla coil audio input.

Our tesla coil will be different from everyone else’s by being able to take in analog audio format and also microphone input. It will be able to “sing” by reading off of a file or repeat after microphone input.

Block Diagram / Flow Chart

System Overview

Voltage dividers are used in the circuit to reduce the voltage going through the components so that they don’t get fried. The power supply will be a 18V power brick. There are two switches, and they must both be toggled on for electricity to flow. This ensures that the tesla coil does not accidentally turn on. The circuit is a transformer with a 1:400 conversion ratio, meaning that the output voltage will be around 400x18=7200V. The circuit accepts analog audio input, which can be from a phone, or the arduino with a microphone that we will build and code. 

Parts

Tesla Coil (All from ECE supply center eg. Digikey)

(x1) 1 uF Ceramic Capacitor $5.96 https://www.digikey.com/en/products/detail/vishay-beyschlag-draloric-bc-components/K105K20X7RF5UH5/2356882

(x1) 1 uF 50V Electrolytic Capacitor $1.45 https://www.digikey.com/en/products/detail/kemet/ESS105M050AB2EA/13930414

(x2) 2 kOhm Resistors $0.50 https://www.digikey.com/en/products/detail/stackpole-electronics-inc/CFM12JT2K00/1741918

(x2) 10 kOhm Resistors (put 5 2 kOhm Resistors in series)

(x1) BD243C Transistor <$1 

(x1) 80NF70 Transistor <$1 Digikey 497-10964-5-ND $2.21

(x2) Transistor Heatsinks $5 https://www.digikey.com/en/products/detail/assmann-wsw-components/V4330N/3511519

(40m) 32 AWG Magnet Wire $10 https://www.digikey.com/en/products/detail/remington-industries/32SNSP-125/11614523

(x2) LED <$1 

(x1) 50 kOhm Potentiometer Digikey 93R1A-R22-A18L-ND $6.99

(x1) Breadboard $5 

(x1) Breadboard Friendly 3.5mm Audio Jack 

Heat Shrink Tubing $5 Digikey Q53X316B-ND $1.84

(x2) Toggle Switches Digikey EG2350-ND $7.77

Arduino + DAC

(x9) 1/4 Watt 20kOhm Resistors Digikey 0KQBK-ND $0.67

(x7) 1/4 Watt 10kOhm Resistors Digikey CF14JT10K0CT-ND $0.36

(x2) TS1872IN Digikey 497-2239-5-ND 

(x1) 10kOhm potentiometer linear Digikey 987-1308-ND $0.85

(x1) 0.01uF capacitor Digikey 445-5252-ND $0.32

(x1) 220uF capacitor Digikey P5183-ND $0.52

(x1) 0.1uF capacitor Digikey 445-5303-ND $0.32

(x1) 1/4 Watt 3kOhm Resistor Digikey CF14JT3K00CT-ND $0.36

(x1) 1/4 Watt 10Ohm Resistor Digikey CF14JT10R0CT-ND $0.36

(x1) Arduino Uno Sparkfun DEV-09950 $22.95

(x1) Microphone $10

Total: <$85

Possible Challenges

High voltage may interfere with electronic devices that are very close, so we need to make sure to keep this in mind when operating the tesla coil.

We have to make a DAC to convert the digital output of the Arduino Uno into an analog signal, which requires coding. If this is too hard, we can buy a pre-made DAC.

We have to wind the secondary coil 400 times. The wire is extremely thin, so this might be difficult.

References

[1] Arduino Projects with DIY Instructions, Codes, Diagram. 2021. Audio Output using an Arduino -. [online] Available at: <https://duino-projects.com/audio-output-using-an-arduino/> [Accessed 20 September 2021].

[2] Youtube.com. 2021. [online] Available at: <https://www.youtube.com/watch?v=mur3dIDo0lI> [Accessed 20 September 2021].

[3] En.wikipedia.org. 2021. Singing Tesla coil - Wikipedia. [online] Available at: <https://en.wikipedia.org/wiki/Singing_Tesla_coil> [Accessed 20 September 2021].