[[:Category:Fachmodul|Fachmodul]]

'''Sound Source - Light Sink'''
''Instructor:'' [[Clemens Wegener]]
''Credits:'' 6 [[ECTS]], 3 [[SWS]]
''Capacity:'' max. 12 students
''Language:'' Deutsch/English by preference
''Location:'' Marienstr. 7, R104

''First Meeting:'' Tue, 17th Oct, 3:15pm - 5:30pm
==Description==
In the course 'Sound Source - Light Sink' we want to deal with the interaction of sound and light. Different possibilities of lighting as well as audio recording and playback will be brought into synchronization. For this purpose we want to control LEDs or DMX spotlights via Auduino synchronously to an audio recording. In a first step we will create a light and sound composition. Afterwards we will learn how sound and light can be translated and synchronized to each other in real time. For this we use the graphical programming language Pure Data.
==Admission requirements==
This course is directed towards beginners in graphical programming in Pure Data or Max/Msp. If possible, a laptop for programming should be brought to the course. In addition, a budget of 20 to 30€ should be planned for the purchase of an Arduino.

If you are interested, please send a letter of motivation and portfolio to clemens.wegener ( at ) uni-weimar (dot) de. Basic knowledge of arduino programming will be taught in the course.

==Evaluation==
Successful completion of the course is dependent on regular attendance, active participation, completion of assignments, delivery of a relevant semester prototype and documentation. Please refer to the [[IFD:IAC SoSe23/EvaluationPIESoSe23|Evaluation Rubric]] for more details.
==Eligible participants==
Qualified BFA/MFA Medienkunst/-gestaltung, MFA Media Art and Design
==Syllabus (tba)==
*Thu, 17.10.
**Meet & greet,
**Short intro
**Needed material

2023-06-14T17:09:09Z

Clemensw: /* Syllabus (updated 9th Jan.) */

[[:Category:Fachmodul|Fachmodul]] 
'''Paper, Ink and Electronics''' 
''Instructor:'' [[Clemens Wegener]] 
''Credits:'' 6 [[ECTS]], 3 [[SWS]] 
''Capacity:'' max. 12 students 
''Language:'' Deutsch/English by preference 
''Location:'' TBA 
''First Meeting:'' Thu, 20th Apr, 9:15 am

==Description==
Printed Electronics can turn everyday objects into interfaces for the digital world.
We will use screen printing with conductive ink to print our own designs on paper, leather, or glass and use them as buttons or slider with the help of microcontrollers such as Arduino. This way we we create objects which serve as input devices for digital functionalities.
We will first take a look at the basic qualities and possibilities of printed electronics, as well as the characteristics of the tools we are going to use. Here we focus on the screen printing methods and the concept of capacitive sensing with Arduino. Students will design their own objects which we will print on and connect to an Arduino.

==Admission requirements==
Knowledge in Hard- and Software would be appreciated, but is not a requirement. For buying electronic components, a little budget of 20€ to 30€ is neccessary. Of course you can keep your manufactured works. Please send a motivational letter to clemens.wegener (at) uni-weimar (dot)de.

==Evaluation==
Successful completion of the course is dependent on regular attendance, active participation, completion of assignments, delivery of a relevant semester prototype and documentation. Please refer to the [[/EvaluationPIEWS21 |Evaluation Rubric]] for more details.

==Eligible participants==
Qualified BFA/MFA Medienkunst/-gestaltung, MFA Media Art and Design 

==Syllabus (updated 14th Jun.)==
* Thu, 20.4.
** Meet & greet,
** Short intro
** Needed material
* Thu, 27.4.
** Introduction to electronics
** Manual circuits & Connections
* Thu, 4.5.
** Workshop 1: manual circuits
* Thu, 11.5. date cancelled
* Thu, 18.5. public holiday
* Thu, 25.5.
** Workshop 2: manual circuits
* Thu, 1.6.
** Arduino programming & libraries
* Thu, 8.6. date cancelled
* Thu, 15.6.
** '''Presentation of project ideas'''
** Project proposals & inspiration sessions
 
* '''22.6.- 13.7. Workshop Sessions & Screen Printing'''
 
* Mo, 20.7. '''Final Presentations'''
* Mo, 30.9. '''Hand in documentation'''

==Course Material==
===Slides===
*[[:File:0. Paper, Ink and Electronics - Intro.pdf |Introduction]]
*[[:File:1. Paper, Ink and Electronics - Intro Electronics.pdf |Electronic circuits]]
*[[:File:2. Paper, Ink and Electronics - Printing Techniques.pdf |Printing techniques]]
*[[:File:3. Paper, Ink and Electronics - Printing Speakers & Microphones.pdf |Printing Speakers & Microphones ]]
===Additional Material===

[http://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAUgpABZsKBTAWjDACgA3cDQkJvKmB58UePFAk0qxCVRgI2Ad269+VbIXFqobbDRCKAFgEsALswDOAWwAmTADYMb4EMWjYUzVlFg0UFWBQwMUIwIIwaYgQ-CXYwQn8UKRExEFx9JlFxfyMzS1sHJxcICBhIFDYAJzTNFPENLQFYuDYAB3Awuo7-bVKdZVYerJUuyCVuviahVSax+P9prqSqTNSck3MmaztHZxKXMor5tMgM4Yalgw38naL90sC2AA9wZKZsDTSEVQ-6fSSQKZDJUGAwADoWAAyAFEACIWCHGAB2EIsDEqxgYFmeFDIfA+MjwhHo70+-30pgA9pSIVYAIZIgCeEJh8MRKIsaIxWIAhGxjhg0F0MHgzmsrnktgVdsUDo9jghiENUoRvpdcpttoU9rLDuMEKJJlRFT1ZvrDatxCbRm0KBbhgbGoJZFVXJ1LW7TXJkHMEiBVaphoKVsN1pKtTL7j5yvqlUbPfGxlxrdoU8NvckZN75Py-SKxeJRVpQxLNdK7rr5X6i11iO6SxqbtrZQ8Yy8PDJQhQEBBCPpySAAGaUgCulRZcIRFmRENadMqdPsjnsfOOHmkvHXJ3+pabkcrMYGnXSIxPYyP-mIvEWV507UGrmvx9OBx0XEWJ5vvAz0lkPgUa6io+aRASeYZlrcOr7Hqyhbre2BAbe55pEKJ4IfoZ7jDQND1C+Pb+JhCqdLe+HbiA4F7hW0FVv42HiLedFkRRUqQS20YVLBoEvoxmGcfoDE4cByGMSRxHfq6X4oRuEgfHMETkckKBqssXwLD6cDRpASAABIjlYxg2GYjIgAAygwSIWJS1TsAMwhgfgZHIWguH-A5Snicoznkcpilqk5apoahL5jC8wTqHgEAeEg6G0K8ICGHpBlGai5mWeOFhzqY5iVEiOJgDQvB9uRxD6IQ5D6PlIAAEStJSijolshjzsiADmVUQiC04WFSlQ4pkGAlPE+L0KwMgVfoACSg4Qoyo4QvO4IWDYGIcK1tIMsyFi7FOM4ZfOi7LgANH1mALJEtALAasWVXSqKtY4HVYsY3VWRCAAUr0WAl+mGaYm1ohZVkAJS0sYLWGKYEItQwkNfZSpjHS8-UjXgSAsOAqTjSAABGDAAMZ0iOaLzRC9jwxClLTRYeNjiCSKw89HUjkiSJrd1hijuDiKmNAJ3ySgqH-CgfxxQAKjSnJNSCEJAotNOVHTCMQvVqKtPYZgy4Yi2dc9PXslSMuKJSvNI5g9BKeQ2DkEQVBY6LJhTliAOmMYB2bU19gcFimuLVrdKw0C-s+5trSVJSNgjnjDAmyIxBUMSvCdtgY1xRNDNThYdKDotBsvZHhiHRC2MjgHWuznSrToqD4Ow9DsOKPOVh8qbeCdpAEDRP63FxbLs51VX7Oc4YPsQt9SV-SlgPpYzFhoJAVgAOrvfSTxA4jXTfEgW+1FjlkjxY0NIui-tOKPDBB5yofnzYU6Ul76UHRTVOy1YMerOQCAeHwQ2f0gWNp4iDOWcB65xasYL2EIGD302qybmt9FAch1i9So694j6BFJFSAMh8zXX0GPX6-1UqfUytlXKnlkgYBfCeSh+hkJgDjAGciAJGF0LjDQ8ADC-LjHiFQdh9D-DsLkkLUqykAQYCuiUeAchYBaRALpWwZhjDGTMlPciuZ-AJH7LeTRXdsi7hYs2KMMEKCEF4S+HRgjxg6MiLwb4tskL6lMbQBiLiPLON4OwuxIBLEKicTYkx8c3L6IjFROUh5aBf38VEhxsEd4MUiTEmo4h2F0AEcFdRETaLxI0UExsBj9zURjMcaJvB-GmL0XkkJUEwkcUyd47it5LGwRfOwi4TSyL+IuP430BE4mblqOU8iwTyzVNbBUd8Ti+F+KQpIX82ZoAKHaK44CfCXTKGWTw9x-QVkvk2T4v0J5OnmNydcfJoSxk4mwGqAqH9CClMobFAE04ngTjZNODkc4FxLgYCubh0zNwNPEtUC4gy2nBTSLgV0J5QUtPBbJV0qTdF1MERCsY1QykOX8Si+F1QvGDK8diyF1QdGDIsXCyFpsHksDAGjO539OhYwAJpzWpgyCmSJ7CbWWuAnOwJQRPx9k3PmEAWBXRkCwc6WNdqjnSgTNEhcLBhxHODTlEJsAADVoAQhMhLQcYcrAkwsMQdVRd-bZUZOvfqKxgjW3ICwICWMoHohgXCCEAByCwI5samAXHjUwFg3WGo4JSewpg6TQwhHqykBrLJjlNVlZ1lqiDioFiSPQIghRY1miOea0svpmBdkiFqM0ZWk2MPpf1EJoEQgAI4jmMHjAA1pygAXCdWomQ1TvDtUpEWlUpolpzZnPN3LVpFvWkyUmTgdoci5JiCwx0gA Series and parallel LEDs ]

==Inspriation==
* [https://www.uni-weimar.de/kunst-und-gestaltung/wiki/IFD:Printed_Electronics_project_documentation Florian Wittig's Course Results in Printed Electronics]

*[https://medium.com/@LiangRR/lessons-in-using-bare-conductive-c1f79cb45b7b Puhe Liang - Interactive wall painting]
*[https://www.instagram.com/p/B5h6LMaFAnB/ Victoria Shen - Speaker portrait]
*[https://www.instagram.com/p/B3kB6kpFYGj/ Victoria Shen - VU-meter earrings]
*[https://vimeo.com/68096627 Jess Rowland - Sound Tapestry]
*[https://vimeo.com/67969655 Jess Rowland - Circuit Print]
*[https://www.instructables.com/Paper-Speakers-1/ Jess Rowland - Paper Speaker Instructable]
*[https://www.kickstarter.com/projects/551648271/papier-machine-vol0-the-interactive-electronic-pap Papier Machine (Kickstarter)]
*[https://vimeo.com/47656204 Waldek Węgrzyn - Elektrobiblioteka]
*[https://newatlas.com/piano-box-paper-synth/22666/ Catarina Mota - Paper Piano Box]
*[https://www.manokel.com/blink Manolis Kelaidis - Blink]
*[https://www.bitbook.ink/ Manolis Kelaidis - Bitbook (to be released in 2022)]

===Papercraft===
* Jackson, Paul: Vom Faltobjekt zum Werbeträger : Schneide- und Falttechniken im Papierdesign. Bern: Haupt Verlag, 2013. ISBN 978-3-258-60070-3 (more releases by Paul Jackson available in the University Library)
* Klanten, Robert (ed.): Papercraft : design and art with paper. Berlin: Die Gestalten Verlag, 2009. ISBN 978-3-89955-251-5 (check out part 2 as well)
* Avella, Natalie: Paper Engineering : Papier als 3D-Werkstoff. München: Stiebner, 2004. ISBN 978-3-8307-1292-3

==Further Reading==
* Yoshihiro Kawahara, Steve Hodges, Benjamin S. Cook, Cheng Zhang, and Gregory D. Abowd. 2013. Instant inkjet circuits: lab-based inkjet printing to support rapid prototyping of UbiComp devices. In Proceedings of the 2013 ACM international joint conference on Pervasive and ubiquitous computing (UbiComp '13). Association for Computing Machinery, New York, NY, USA, 363–372. [https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/ubi1415-instant20inkjet.pdf (link to pdf)]
* Suganuma, Katsuaki: Introduction to Printed Electronics. New York: Springer Science+Business Media, 2014.

* Y. Kawahara, S. Hodges, N. Gong, S. Olberding and J. Steimle, "Building Functional Prototypes Using Conductive Inkjet Printing," in IEEE Pervasive Computing, vol. 13, no. 3, pp. 30-38, July-Sept. 2014.

* Murray-Smith, Roderick & Williamson, John & Hughes, Stephen & Quaade, Torben. (2008). Stane: Synthesized surfaces for tactile input. Conference on Human Factors in Computing Systems - Proceedings. 1299-1302. 10.1145/1357054.1357257.

* Simon Olberding, Nan-Wei Gong, John Tiab, Joseph A. Paradiso, Jürgen Steimle. A Cuttable Multi-touch Sensor. Proceedings of UIST'13.

* Lengwiler, Guido: Die Geschichte des Siebdrucks: Zur Entstehung des vierten Druckverfahrens. Sulgen: Niggli, 2013. ISBN 978-3-7212-0876-4

2023-01-19T15:29:20Z

Clemensw:

Here you find learning material in the form of circuit simulations, that lead you to the understanding of amplifiers and other signal conditioning circuits that we use throughout the course. Feel free to experiment with them, they are editable and saved via the encoded URL. You cannot destroy them and it is easy to share edited versions. [http://bait-consulting.com/publications/circuit_simulator_manual.pdf Here] is an introduction to the circuit simulator.

* The foundation of understanding electric circuits is Ohm's law.
[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+10.20027730826997+50+5+43%0Ar+-240+-48+-64+-48+0+1000%0Av+-240+32+-240+-48+0+0+40+5+0+0+0.5%0A370+-64+-48+-64+32+1+0%0Ax+1+34+255+37+4+18+I%5Cs%5Cq%5CsU%5Cs/%5CsR%5Cs%5Cq%5Cs5%5CsV%5Cs/%5Cs1%5CskOhm%5Cs%5Cq%5Cs5%5CsmA%0Ax+-311+-88+330+-85+4+18+This%5Csshows%5Cshow%5Csto%5Cscalculate%5Csthe%5Cscurrent%5Csrunning%5Csthrough%5Csa%5Csresistor%5Csby%5CsOhm's%5Cslaw.%0Ax+-315+101+243+104+4+12+The%5Csvoltage%5Cssource%5Cson%5Csthe%5Csleft%5Cshas%5Cs5V,%5Cswhich%5Csforce%5Csa%5Cscurrent%5Csto%5Csrun%5Csthrough%5Csthe%5Csresistor%5Cswith%5Cs1000%5CsOhms.%0Ax+-317+127+114+130+4+12+%5CsThe%5Csresistor%5Cslimits%5Csthe%5Cscurrent%5Csto%5Cs5%5CsmA%5Cs(milli-Ampleres)%5Csaccording%5Csto%5CsOhm's%5Cslaw.%0Ax+-1+-6+67+-3+4+18+U%5Cs%5Cq%5CsR%5Cs*%5CsI%0Aw+-240+32+-240+48+0%0Aw+-240+48+-64+48+0%0Aw+-64+48+-64+32+0%0Ap+-304+-48+-304+48+1+0%0Aw+-304+48+-240+48+0%0Aw+-304+-48+-240+-48+0%0Ax+-310+-138+-227+-135+4+18+Ohm's%5Cslaw%0Ao+2+64+0+4099+0.0000762939453125+0.00625+0+2+2+3%0A Ohm's Law]
* We can calculate series and parallel resistances with Ohm's law:
[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+45.7144713268909+50+5+43%0Ax+-483+108+-368+111+4+16+R_tot%5Cs%5Cq%5CsR1%5Cs%5Cp%5CsR2%0Ax+-469+-262+-224+-259+4+18+Series%5Csand%5CsParallel%5CsResistance%0Ax+-483+57+-330+60+4+12+Series%5CsResistances%5Csadd%5Csup!%0Ax+-501+-140+-485+-137+4+12+R1%0Ax+-500+-53+-484+-50+4+12+R2%0Ar+-464+-96+-464+16+0+1000%0Ar+-464+-192+-464+-96+0+1000%0A216+-400+16+-400+-192+0+0.01%0Aw+-400+-192+-464+-192+0%0Aw+-464+16+-400+16+0%0Aw+-96+16+-16+16+0%0Aw+-16+-192+-96+-192+0%0A216+64+16+64+-192+0+0.01%0Ar+-176+-192+-176+16+0+1000%0Ar+-96+-192+-96+16+0+1000%0Ax+-134+-84+-118+-81+4+12+R2%0Ax+-216+-86+-200+-83+4+12+R1%0Ax+-181+55+48+58+4+12+Parallel%5CsResistances%5Cshave%5Csan%5Csinverse%5Cslaw:%0Ax+-177+104+132+107+4+16+1%5Cs/%5CsR_tot%5Cs%5Cq%5Cs1/R1%5Cs%5Cp%5Cs1/R2%5Cs%5Cp%5Cs1/R3%5Cs%5Cp%5Cs...%5Cs%5Cp%5Cs1/R_n%0Aw+-176+-192+-96+-192+0%0Aw+-176+16+-96+16+0%0Ar+-16+-192+-16+16+0+1000%0Aw+-16+-192+64+-192+0%0Aw+-16+16+64+16+0%0Ax+-50+-84+-34+-81+4+12+R2%0A series and parallel resistances]

* A very powerful concept is the voltage divider, it allows us to attenuate (but not amplify!) any voltage in any circuit
[http://tinyurl.com/yxhsk8sc voltage divider with even resistors]

== Amplifiers (and Attenuators) ==

* We will use the OpAmp (=operational amplifier) to amplify the small signals from our microphones to usable and less noisy signals before we digitize them in the computer. The opamp (= operational amplifier) is a three port device and its circuit diagram is a triangle. It has a positive and a negative input terminal and an output terminal. The most basic opamp circuit is the "comparator".
[http://tinyurl.com/yxrdh8gx opamp as a comparator]

* the opamp's output can also directly follow one of its input voltages, but providing more current. This is the basis building block of opamp based amplifiers and is called "voltage follower" or "buffer".

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+10.20027730826997+50+5+43%0Ag+-384+-48+-384+-32+0%0Av+-384+-48+-384+-128+0+1+100+5+0+0+0.5%0Ag+-272+-48+-272+-32+0%0Ax+-496+-235+-330+-232+4+18+The%5CsSource%5CsFollower%0Ax+-506+33+181+36+4+12+Once%5Csyou%5Csapply%5Csa%5Csfeedback%5Cspath%5Csfrom%5Csthe%5Csopamp's%5Csoutput%5Csto%5Csthe%5Csnegative%5Csinput,%5Csthe%5Csoutput%5Csvoltage%5Csdirectly%5Csfollws%5Csthe%5Csinput%5Csvoltage.%0Ax+-506+57+-440+60+4+12+Why%5Csis%5Csthat?%0Ax+-506+82+-3+85+4+12+When%5Csthe%5Cssinwave%5Csof%5Csthe%5Cspositive%5Csinput%5Csgoes%5Csup,%5Csthe%5Csoutput%5Cswill%5Csalso%5Csgo%5Csup%5Cs(with%5Csvery%5Cshigh%5Csgain).%0Ax+-509+109+299+112+4+12+%5CsBut%5Cssince%5Csthis%5Cshigh%5Csgain%5Cssignal%5Csis%5Csreflected%5Csback%5Csto%5Csthe%5Csnegative%5Csinput%5Csit%5Cswill%5Cscounteract%5Cson%5Csthe%5Csoutput,%5Csforcing%5Csthe%5Csoutput%5Cseven%5Csmore%5Csto%5Csthe%5Csminus%5Csdirection.%5Cs%0Aa+-384+-144+-272+-144+8+15+-15+1000000+2.8621324318134485+2.8621610531377666+100000%0Ap+-272+-144+-272+-48+1+0%0Aw+-272+-144+-240+-144+0%0A207+-240+-144+-192+-144+0+output%0A207+-384+-128+-416+-128+0+input%0Aw+-272+-144+-272+-208+0%0Aw+-272+-208+-384+-208+0%0Aw+-384+-208+-384+-160+0%0Ax+-508+134+367+137+4+12+However,%5Csfeedback%5Csis%5Csan%5Csendless%5Csprocess%5Csand%5Csas%5Cssuch%5Csthe%5Csforce%5Csto%5Csthe%5Csminus%5Csdirection%5Cswill%5Csbe%5Csreflected%5Csback%5Csto%5Csthe%5Csinput%5Csagain,%5Csforcing%5Csthe%5Csoutput%5Csto%5Csbe%5Cspositive%5Csagain.%0Ax+-510+164+175+167+4+12+All%5Csthose%5Cspositive%5Csand%5Csnegative%5Csforces%5Cswill%5Csmagically%5Cssum%5Csup%5Csin%5Csevery%5Csmoment%5Csin%5Cstime,%5Csforcing%5Csthe%5Csoutput%5Csto%5Csexactly%5Csfollow%5Csthe%5Csinput!%0Ax+-510+195+87+198+4+12+This%5Cscircuit%5Csis%5Csalso%5Cscalled%5Csa%5Cs%22buffer%22%5Cssince%5Csit%5Cscan%5Csbe%5Csused%5Csto%5Csrepeat%5Csa%5Csweak%5Cssignal.%5CsMeaning%5Csamplifiying%5Csthe%5Cscurrent,%5Cs%0Ax+-511+222+-63+225+4+12+since%5Csthe%5Csopamp%5Cscan%5Csprovide%5Csmore%5Cscurrent%5Csat%5Csthe%5Csouput%5Csthen%5Csis%5Csavailable%5Csat%5Csits%5Csinputs.%0Ao+9+64+0+4098+20+0.1+0+3+1+0+1+3%0A stabilized opamp as a source follower]

* once you provide a voltage divider circuit in the feedback loop of an voltage follower, you are able to control the gain of the output port. This means the voltage of the output can be a scaled version of the input, either attenuating or amplifying the input voltage. Depending on whether the voltage divider is applied on the positive or negative input, the output is an inverted or non-inverted version of the input voltage. The two basic building blocks are shown below.

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+10.20027730826997+50+5+43%0Ag+-448+0+-448+16+0%0Av+-448+0+-448+-64+0+1+100+1+0+0+0.5%0Ax+-408+-151+-228+-148+4+18+The%5CsInverting%5CsAmplifier%0Aa+-304+0+-192+0+8+15+-15+1000000+-0.00008339866952988274+0+100000%0A207+-192+0+-144+0+4+output%0Aw+-192+0+-192+-64+0%0Aw+-304+-64+-304+-16+0%0Ar+-288+-64+-208+-64+0+10000%0Aw+-288+-64+-304+-64+0%0Aw+-208+-64+-192+-64+0%0Ar+-448+-64+-304+-64+0+1000%0Ag+-304+16+-304+48+0%0Ax+-319+82+-162+85+4+12+Gain%5Cs%5Cq%5CsR2%5Cs/%5CsR1%5Cs%5Cq%5Cs10k/1K%5Cs%5Cq%5Cs10%0Ax+-253+-41+-238+-38+4+12+R2%0Ax+-383+-42+-368+-39+4+12+R1%0Ax+-467+-73+-437+-70+4+14+input%0Ao+1+64+0+4098+5+0.1+0+2+1+3%0Ao+4+64+0+4098+20+0.00009765625+1+2+4+3%0A Inverting Opamp]

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+10.20027730826997+50+5+43%0Ag+-448+80+-448+96+0%0Av+-448+80+-448+16+0+1+100+1+0+0+0.5%0Ax+-411+-158+-192+-155+4+18+The%5CsNon-Inverting%5CsAmplifier%0Aa+-304+0+-192+0+8+15+-15+1000000+0.6913109108869245+0.691386955087122+100000%0A207+-192+0+-144+0+4+output%0Aw+-192+0+-192+-64+0%0Aw+-304+-64+-304+-16+0%0Ar+-288+-64+-208+-64+0+10000%0Aw+-288+-64+-304+-64+0%0Aw+-208+-64+-192+-64+0%0Ar+-448+-64+-304+-64+0+1000%0Aw+-448+16+-304+16+0%0Ag+-448+-64+-448+-32+0%0Ax+-344+68+-147+71+4+12+Gain%5Cs%5Cq%5Cs1%5Cs%5Cp%5CsR2%5Cs/%5CsR1%5Cs%5Cq%5Cs1%5Cs%5Cp%5Cs10k/1K%5Cs%5Cq%5Cs11%0Ax+-253+-41+-238+-38+4+12+R2%0Ax+-383+-42+-368+-39+4+12+R1%0Ax+-469+11+-439+14+4+14+input%0Ao+1+64+0+4098+5+0.1+0+2+1+3%0Ao+4+64+0+4098+20+0.00009765625+1+2+4+3%0A Non-Inverting Opamp]

== Oscillators ==

* We can use a special configuration of the Opamp together with a capacitor as a simple oscillator. The following simulation is a square wave oscillator. At the positive input terminal, there is a voltage divider, that divides down the output of the opamp in half. Since it is positive feedback, the opamp will drive to the maximum point, which in our case is +-15V. The voltage divider divides this voltage down to half. Depending on whether the output drives high or low, the voltag at the positive input is thus +-7.5V. The capacitor gets constantly charged and discharged from the output of the opamp through the resistor. The voltage at the capacitor on the negative input compares to this threshold voltage and inverts the signal when it exceeds the respective treshold. Since this process is endlessly repeating, the output oscillates. The frequency is dependend on the size of the capacitor and the resistance of the negative feedback resistor.

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ag+-240+96+-240+112+0%0Ax+-134+-188+297+-185+4+18+Self-Oscillating%5CsComparator%5Cs(Square%5CsWave%5CsGenerator)%0Aa+-240+0+-128+0+8+15+-15+1000000+6.090293760309295+7.500070481327725+100000%0Aw+-128+0+-96+0+0%0Ag+-304+-16+-304+0+0%0A207+-96+0+-48+0+4+output%0Ac+-304+-16+-240+-16+0+1.0000000000000001e-7+-6.090293760309295%0Ar+-240+48+-240+96+0+100000%0Ar+-240+48+-128+48+0+100000%0Aw+-240+16+-240+48+2%0Aw+-128+0+-128+48+0%0Ar+-240+-64+-128+-64+0+100000%0Aw+-128+-64+-128+0+0%0Aw+-240+-64+-240+-16+2%0Ao+9+64+0+4098+10+0.00009765625+0+2+9+3%0Ao+13+64+0+4098+10+0.00078125+1+2+13+3%0A Square Wave Generator]

[[file: square_wave_oscillator.png]] This is the breadboard version of the square wave oscillator. The output frequency should be around 50-100Hz. You can connect this to a small speaker or headphone directly. To connect it to a Hifi amplifier input, you need to convert the output voltage from around +-4V to +-1V by using a voltage divider, as shown in the second version with the potentiometer. In this circuit I use the 4-band resistor color marking.

[[file: square_wave_oscillator_potentiometer.png]] This is the breadboard version of the square wave oscillator with potentiometer and output to +-1V (suitable for a hifi input (aux)). The output frequency varies with the potentometer. In this circuit you will find the 5-band resistor color marking. Beware: the output voltage divider before the cinch (RCA) connector is a 10kOhm and a 2kOhm resistor. Anything approximate in a 5:1 Ratio should do the trick and attenuate the output voltage below +-1V.

== Filters ==

* To shape the spectrum of our oscillators we will use a lowpass filter. The simplest form of a lowpass filter is the passive lowpass filter. You can view this lowpass filter as an elaborated voltage divider: the capacitor has a frequency dependent resistance (which we call an impedance). This impedance is very high for static voltages (DC) and low frequencies. The impedance goes down the higher the frequency is at its input. The higher the frequency, the lower the impedance at the capacitor and the lower will be the voltage at the capacitor. This will effectively filter out high frequencies and leave lower frequencies in the signal.

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ag+-192+-64+-192+-48+0%0Ax+-196+-216+-12+-213+4+18+Passive%5CsLowpass%5CsFilter%0Aw+-192+-128+-160+-128+0%0A207+-160+-128+-112+-128+4+output%0Ac+-192+-128+-192+-64+0+1.0000000000000001e-7+0.6852026285128602%0Ar+-192+-128+-288+-128+0+1000%0AR+-288+-128+-336+-128+0+1+1591.5+1+0+0+0.5%0Ax+-13+-92+91+-89+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*R*C)%0Ax+-14+-67+180+-64+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*10%5E3%5CsOhm*10%5E-7%5CsF)%0Ax+-14+-40+156+-37+4+14+f%5Cs%5Cq%5Cs10%5E4%5Cs/%5Cs(2*pi)%5Cq10000/%5Cs2pi%0Ax+-14+-12+69+-9+4+14+f%5Cs%5Cq%5Cs1591,5%5CsHz%0Ax+-13+-130+293+-127+4+14+Calculation%5Csof%5Csfilter%5Cscutoff%5Cspoint%5Cs(-3dB%5CsFrequency)%0Ao+3+4+0+4106+1.25+0.00009765625+0+2+3+3%0A Passive Lowpass Filter]

* The passive low pass filter has the same disadvantage as the voltage divider: the output cannot be loaded without changing its characteristics. To prevent this, we can just put a buffer at the output of the low pass filter.

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ag+-256+32+-256+48+0%0Ax+-164+-202+66+-199+4+18+Simple%5CsActive%5CsLowpass%5CsFilter%0Aw+-256+-32+-224+-32+0%0A207+-112+-48+-64+-48+4+output%0Ac+-256+-32+-256+32+0+1.0000000000000001e-7+0.41109475569201465%0Ar+-256+-32+-352+-32+0+1000%0AR+-352+-32+-400+-32+0+1+1591.5+1+0+0+0.5%0Ax+-13+-92+91+-89+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*R*C)%0Ax+-14+-67+180+-64+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*10%5E3%5CsOhm*10%5E-7%5CsF)%0Ax+-14+-40+156+-37+4+14+f%5Cs%5Cq%5Cs10%5E4%5Cs/%5Cs(2*pi)%5Cq10000/%5Cs2pi%0Ax+-14+-12+69+-9+4+14+f%5Cs%5Cq%5Cs1591,5%5CsHz%0Ax+-13+-130+293+-127+4+14+Calculation%5Csof%5Csfilter%5Cscutoff%5Cspoint%5Cs(-3dB%5CsFrequency)%0Aw+-224+-112+-224+-64+0%0Aw+-112+-112+-224+-112+0%0Aw+-112+-48+-112+-112+0%0Aa+-224+-48+-112+-48+8+15+-15+1000000+0.4110906447855668+0.41109475569201465+100000%0Ao+3+4+0+4106+1.25+0.00009765625+0+2+3+3%0A Simple Active Lowpass Filter]

* We can use this simple topologie to connect it to our breadboarded oscillator as you can see on the following fritzing breadboard drawing:

[[file:oscillator_potentiometer_filter.png]]

* Still, since the resistance of our source adds to our first resistor, the cutoff point will change, when the resistance of the source changes. To mitigate this we can change the topologie of our filter like so:

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ax+-164+-202+6+-199+4+18+Active%5CsLowpass%5CsFilter%0A207+-128+0+-80+0+4+output%0Ac+-128+-112+-240+-112+0+1.0000000000000001e-7+-0.06865131933234453%0Ar+-128+-64+-240+-64+0+1000%0AR+-336+-64+-384+-64+0+1+1591.5+1+0+0+0.5%0Ax+-13+-92+99+-89+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*R2*C)%0Ax+-14+-67+180+-64+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*10%5E3%5CsOhm*10%5E-7%5CsF)%0Ax+-14+-40+156+-37+4+14+f%5Cs%5Cq%5Cs10%5E4%5Cs/%5Cs(2*pi)%5Cq10000/%5Cs2pi%0Ax+-14+-12+69+-9+4+14+f%5Cs%5Cq%5Cs1591,5%5CsHz%0Ax+-13+-130+293+-127+4+14+Calculation%5Csof%5Csfilter%5Cscutoff%5Cspoint%5Cs(-3dB%5CsFrequency)%0Aw+-240+-64+-240+-16+0%0Aw+-128+0+-128+-64+0%0Aa+-240+0+-128+0+8+15+-15+1000000+6.865063282601628e-7+0+100000%0Aw+-240+-112+-240+-64+0%0Ar+-240+-64+-336+-64+0+1000%0Ag+-240+16+-240+32+0%0Aw+-128+-112+-128+-64+0%0Ax+-298+-40+-280+-37+4+14+R1%0Ax+-194+-40+-176+-37+4+14+R2%0Ax+-14+42+81+45+4+14+-R2/R1%5Cs...%5CsGain%0Ax+-14+95+226+98+4+14+R2%5Cs...%5CsSets%5Cscutoff%5Csfrequency%5Cs(and%5Csgain)%0Ax+-14+69+83+72+4+14+R1%5Cs...%5CsSets%5Csgain%0Ao+1+4+0+4106+1.25+0.00009765625+0+2+1+3%0A Active Low Pass Filter]

* Unfortunately we can't set the cutoff frequency independently of the gain of our filter with just one resistor (e.g. a potentiometer). With another filter topology, the "bridged T low pass filter", we can tune the filter without changing its gain. To get a bridged T filter, we exchange the capacitor in the feedback loop with two capacitors in series and add a resistor.

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ax+-167+-245+39+-242+4+18+Bridged%5CsT%5CsLow%5CsPass%5CsFilter%0A207+-112+0+-80+0+4+output%0Ac+-176+-192+-240+-192+0+1.0000000000000001e-7+0.07208828582967249%0Ar+-112+-64+-240+-64+0+1000%0AR+-320+-64+-368+-64+0+6+1591+1+0+0+0.5%0Ax+-20+-133+185+-130+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*sqrt(R1*R2*C1*C2)))%0Ax+-21+-108+173+-105+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*10%5E3%5CsOhm*10%5E-7%5CsF)%0Ax+-21+-81+149+-78+4+14+f%5Cs%5Cq%5Cs10%5E4%5Cs/%5Cs(2*pi)%5Cq10000/%5Cs2pi%0Ax+-21+-53+62+-50+4+14+f%5Cs%5Cq%5Cs1591,5%5CsHz%0Ax+-20+-171+170+-168+4+14+Calculation%5Csof%5Csfilter%5Cscutoff%5Cspoint%0Aw+-240+-64+-240+-16+0%0Aw+-112+0+-112+-64+0%0Aa+-240+0+-112+0+8+15+-15+1000000+8.53353504561735e-8+0+100000%0Aw+-240+-192+-240+-64+0%0Aw+-112+-192+-112+-64+0%0Ax+-181+-37+-163+-34+4+14+R1%0Ax+-210+-152+-192+-149+4+14+R2%0Ax+-14+42+81+45+4+14+-R2/R1%5Cs...%5CsGain%0Ax+-14+95+157+98+4+14+R2%5Cs...%5CsSets%5Cscutoff%5Csfrequency%0Ax+-14+69+83+72+4+14+R3%5Cs...%5CsSets%5Csgain%0Ac+-112+-192+-176+-192+0+1.0000000000000001e-7+-0.08062190621064029%0Ar+-320+-64+-240+-64+0+1000%0Ag+-240+16+-240+48+0%0Ar+-176+-192+-176+-128+0+1000%0Ag+-176+-128+-176+-112+0%0Ax+-291+-36+-273+-33+4+14+R3%0Ax+-13+123+276+126+4+14+R1%5Cs...%5CsThe%5Csbigger%5CsR1,%5Csthe%5Csmore%5CsQ%5Cs(resonance)%0Ao+1+4+0+5128+2.5+0.00009765625+0+2+1+3%0A Bridged T Low Pass Filter]

* modifiying the capacitor and resistor values, we can use a 100k potentiometer to have a variable cutoff frequency filter

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+12.050203812241895+54+5+43%0Ax+-167+-245+39+-242+4+18+Bridged%5CsT%5CsLow%5CsPass%5CsFilter%0A207+-112+0+-80+0+4+output%0Ac+-176+-192+-240+-192+0+2e-9+0.09900202645250962%0Ar+-112+-64+-240+-64+0+100000%0AR+-320+-64+-368+-64+0+6+1591+1+0+0+0.5%0Ax+-20+-133+183+-130+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*sqrt(R1*R2*C1*C2)))%0Ax+-21+-108+173+-105+4+14+f%5Cs%5Cq%5Cs1%5Cs/%5Cs(2*pi*10%5E3%5CsOhm*10%5E-7%5CsF)%0Ax+-21+-81+147+-78+4+14+f%5Cs%5Cq%5Cs10%5E4%5Cs/%5Cs(2*pi)%5Cq10000/%5Cs2pi%0Ax+-21+-53+62+-50+4+14+f%5Cs%5Cq%5Cs1591,5%5CsHz%0Ax+-20+-171+167+-168+4+14+Calculation%5Csof%5Csfilter%5Cscutoff%5Cspoint%0Aw+-240+-64+-240+-16+0%0Aw+-112+0+-112+-64+0%0Aa+-240+0+-112+0+8+15+-15+1000000+-0.000002138187387850065+0+100000%0Aw+-240+-192+-240+-64+0%0Aw+-112+-192+-112+-64+0%0Ax+-181+-37+-164+-34+4+14+R1%0Ax+-210+-152+-193+-149+4+14+R2%0Ax+-14+42+79+45+4+14+-R3/R1%5Cs...%5CsGain%0Ax+-14+95+154+98+4+14+R2%5Cs...%5CsSets%5Cscutoff%5Csfrequency%0Ax+-14+69+81+72+4+14+R3%5Cs...%5CsSets%5Csgain%0Ac+-112+-192+-176+-192+0+2e-9+0.11481885051988475%0Ar+-320+-64+-240+-64+0+100000%0Ag+-240+16+-240+48+0%0Ag+-176+-128+-176+-112+0%0Ax+-291+-36+-274+-33+4+14+R3%0Ax+-13+123+269+126+4+14+R1%5Cs...%5CsThe%5Csbigger%5CsR1,%5Csthe%5Csmore%5CsQ%5Cs(resonance)%0A174+-176+-192+-176+-128+1+100000+0.33170000000000005+Cutoff%0Aw+-160+-160+-128+-160+0%0Aw+-128+-160+-128+-128+0%0Aw+-128+-128+-176+-128+0%0Ao+1+4+0+5128+2.5+0.00009765625+0+2+1+3%0A Variable Cutoff Active Filter]

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000005+9.001713130052181+54+5+43%0Ax+-132+-156+68+-153+4+18+Triangle%5Cs/%5CsSaw%5CsGenerator%0Aa+-240+0+-128+0+8+15+-15+1000000+0+3.6818713027031436+100000%0Ag+16+32+16+64+0%0A207+128+16+176+16+4+output%0Ac+16+-64+128+-64+0+1e-8+0.5101696765160468%0Ar+-240+48+-240+128+0+100000%0Ar+-240+48+-128+48+0+270000%0Aw+-240+16+-240+48+2%0Aw+-128+0+-128+48+0%0Ar+-64+0+16+0+0+100000%0Ad+-80+-64+-128+-64+2+default%0Aa+16+16+128+16+8+15+-15+1000000+0.000005101645748702981+0+100000%0Aw+16+-64+16+0+0%0Aw+128+-64+128+16+0%0Aw+128+16+128+128+0%0Aw+128+128+-240+128+0%0Ag+-240+-16+-288+-16+0%0Ag+-64+64+-64+80+0%0Ar+-64+0+-64+64+0+50000%0Ar+-128+0+-64+0+0+50000%0Aw+-128+-64+-128+0+0%0Ar+-80+-64+-32+-64+0+1000%0As+-32+-64+16+-64+0+1+false%0Ax+-21+-87+5+-84+4+8+triangle%0Ax+-16+-44+-3+-41+4+8+saw%0Ao+7+8+0+4098+20+0.00009765625+0+2+7+3%0Ao+8+8+0+4106+20+0.1+1+2+8+3%0Ao+3+8+0+4106+20+0.1+2+2+3+3%0A Trianlge / Saw Generator]

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000002834467120181406+135.0639324902207+46+5+43%0Ax+-120+-147+80+-144+4+18+Triangle%5Cs/%5CsSaw%5CsGenerator%0Aa+-240+0+-128+0+8+15+-15+1000000+0+4.806568600947969+100000%0Ag+16+32+16+64+0%0A207+128+16+176+16+4+output%0Ac+16+-64+128+-64+0+1e-8+-1.0310559332974805%0Ar+-240+48+-240+128+0+100000%0Ar+-240+48+-128+48+0+270000%0Aw+-240+16+-240+48+2%0Aw+-128+0+-128+48+0%0Ar+-48+0+16+0+0+100000%0Ad+-80+-64+-128+-64+2+default%0Aa+16+16+128+16+8+15+-15+1000000+-0.000010310456228412521+0+100000%0Aw+16+-64+16+0+0%0Aw+128+-64+128+16+0%0Aw+128+16+128+128+0%0Aw+128+128+-240+128+0%0Ag+-240+-16+-288+-16+0%0Ag+-48+48+-48+80+0%0Ar+-128+0+-48+0+0+1000%0Aw+-128+-64+-128+0+0%0Ar+-80+-64+-32+-64+0+1000%0As+-32+-64+16+-64+0+0+false%0Ax+-21+-87+5+-84+4+8+triangle%0Ax+-16+-44+-3+-41+4+8+saw%0At+-96+32+-48+32+0+1+-13.041485811299184+0.6007456124791911+100%0Aw+-48+0+-48+16+0%0AR+-96+96+-96+176+0+3+1+0.1+0.7000000000000001+0+0.5%0Ar+-96+96+-96+32+0+1000%0A211+128+128+240+128+0+10+44100+1%0A210+128+128+288+80+0+10240%0Ax+-53+181+48+184+4+12+linear%5Csfrequency%5Cscv%0Ao+3+8+0+5130+20+0.1+0+2+3+3%0Ao+26+8+0+4098+1.25+0.1+1+2+26+3%0A Trianlge / Saw Generator Lin Freq CV]

[http://www.falstad.com/circuit/circuitjs.html?cct=$+1+0.000002834467120181406+382.76258214399064+46+5+43%0Ax+-120+-147+80+-144+4+18+Triangle%5Cs/%5CsSaw%5CsGenerator%0Aa+-240+0+-128+0+8+15+-15+1000000+0+1.4845784322226052+100000%0Ag+16+32+16+64+0%0A207+128+16+176+16+4+output%0Ac+16+-64+128+-64+0+1e-8+3.521223450236402%0Ar+-240+48+-240+128+0+100000%0Ar+-240+48+-128+48+0+270000%0Aw+-240+16+-240+48+2%0Aw+-128+0+-128+48+0%0Aa+16+16+128+16+8+15+-15+1000000+0.00003521188238354018+0+100000%0Aw+16+-64+16+0+0%0Aw+128+-64+128+16+0%0Aw+128+16+128+128+0%0Aw+128+128+-240+128+0%0Ag+-240+-16+-288+-16+0%0Ax+-21+-87+5+-84+4+8+triangle%0Ax+-16+-44+-3+-41+4+8+saw%0AR+-64+80+-64+176+0+3+1+0.013000000000000001+-0.516+0+0.5%0Ar+-64+80+-64+32+0+10000%0A211+128+128+240+128+0+2+44100+1%0Ax+-27+183+106+186+4+12+exponential%5Csfrequency%5Cscv%0At+288+-32+288+-64+0+1+0+0+100%0Aw+-80+0+-128+0+0%0Aw+-48+0+16+0+0%0At+-64+32+-64+0+0+-1+-0.6058865273185745+14.394226703642264+100%0Ao+3+8+0+5130+10+0.1+0+2+3+3%0Ao+17+8+0+4098+1.25+0.1+1+2+17+3%0Ao+8+8+0+4098+20+0.1+2+2+8+3%0A Trianlge / Saw Generator Exp Freq CV]

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Oscillators, Filter and Gate]

IFD:IAC WiSe22/sensors and interface schematics

2023-01-19T15:26:40Z

Clemensw:

IFD:IAC WiSe22/sensors and interface schematics

2023-01-19T15:24:55Z

Clemensw: Created page with "This page shows a few ways to sense touch or force and convert it to an analog voltages. [http://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCAMB0l3BWEAWB0DsZnMwZgEwBsAHA..."

This page shows a few ways to sense touch or force and convert it to an analog voltages.

[http://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCAMB0l3BWEAWB0DsZnMwZgEwBsAHAJySkgKRUq5UCmAtGGAFABOITyhy3YdIW7IwwlkKjg4nEWIGSmuEguE0wMrkvw0J4-OnyqpGyLKUq93ArsFrpZrXeMt8xY+s0C3L4rcmejtz4+PxW4c6B5gZG4SFhkQ7mfi4EHklaaVbyVlFcfMassYmmsjnOBblJAObcCGDFivXFPjRmAM7WjeJZBeogAC4cAK4MbJ3lkjl94IMjY52VFWEzEEOj4+ANhdtMq3MbAEpb3SfBCPY0yP1tUNAIbADucuKVyu57-GbPFh9vOtw+k8urpKjFAV9gUxwZ9gqEIVAofEEeEgT9nLDXH9IeifJiUrDvtwCf8EUTtAjpjjwK9+JU0SB6fwimS2ABDcDYYk0UK6FLuMBIFhIUzwWxgaCkKXEPxwVhS0hkbwOeDArBhUjCdXedxE7VYkC8nWI55Gg1mlJ6rmwlmEzZMAkYklfWbrBbGiJ4-Zu+0Yv2Kb3ze3IuLwwmuoOdaGGFwwwMbKM2VIA8NrSPWSwY95kiMJl4uUS0kwHMYAeUN125IFwCFiKQg7CjvASimbObTGx+bcxhdZXaWTV2kTYxx4BRybctUkrrikbXu5jbE6ZJjFMgAHhXxKJDUqlO5mUYAF7DAA67QAkgAZADKAFE2JuQsVKARxPJD+AAGoAelLAGMBnPABBAA7dp-wACwAG2Gdp2kfRlYlwSAkBQ9BrEgIxPwAWwASyA9obwABzZUDQOGUDqgGBg8OghgOHPSiABNz1LUicOI88OAYNloLw9o8IYgZEMICBtAFBAPgIJBPxIsiKKogBHUZoPo0TYjcdR8EoaMMM-ao8IAI0IsAv3PNk4LYIA 1V/Oct analog keyboard interface]

This is a vintage style analog keyboard interface that is used e.g. on the stylophone to convert touches to pitches in 1V/Oct. More sophisticated version with note priority and touch/release detection can be found on [http://musicfromouterspace.com/analogsynth_new/SINGLEBUSSKEYBOARD2007/SINGLEBUSSKEYBOARD2007.php music from outer space].

[http://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCAMB0l3BWcMBMcUHYMGZIA4UA2ATmIxAUgpABZsKBTAWjDACgAnEJ4wqb3iEFUw8SGzAYaAvixrSmeKkxp5wyMVFiQkAMQCWAOwDmDLgAUODAM7WArlbYB3GfxZ8qKNgCUQKFAqC-gqSHvw0Iij8VDAIEoRRwa5J7n4gACYMAGYAhnYANgAuTPkM6eoxWpDsXElgfEnCfvBsxn4BQg0d9ZXiLin1fhhRqV6F4MRRnh2VEDzQCCgIYAQIZLxgNKxaCAh4xAhYNGtgaIR0GhnZeUWcE1Od0Rpwzo-KgzGvPHxBHcKvKUEimU-wAHtxsLJTkhsGoWP5aOAojl8vl9MYcoUAPYcAA61gAxmiAA5scEsPBzC4sSDkFRUaSnEAotEY7F4wkksl+bDEcDYaTYMD0YXkRnI1HozE4-FE-Sk8EBEbC+hCqG4RFMllS9myrnkyRw+pGyB89xIRl8YlWWwOBhfIGqVyfA2EOmnEKbbinCCWkDWBiGaw47lLOa7PwEbiLTV8AAyAFEACLcphoZU0d2ib3yWMgGXWAC2WP01kKdrYQA Velostat Pressure Sensor / Moisture-to-Voltage converter]

This circuit can be used to detect finger pressure or any force on a surface with the help of a pressure sensitive sheet material called 'velotstat'. You can find a tutorial how to build the physical sensor [https://learn.bela.io/tutorials/pure-data/sensors/diy-pressure-sensor/ here].

The same circuit can be used with a different type of physical interfaces as well. Instead of the velostat material as a variable resistor we can use a layout of wires known as a 'moisture sensor'.
We can hookup our moisture sensor to the circuit above instead of the velostat sandwiched between two electrodes.
[https://www.youtube.com/watch?v=DT6nZsixP0M Here] is a video showing how to build a moisture sensor. [https://ciat-lonbarde.net/tocante/index.html Ciat Lonbarde's Tocante] instrument might use this simple technique to sense touch.

[http://www.falstad.com/circuit/circuitjs.html?ctz=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-dAwN6mN7hN6wNBgf74z6fbCkxVHZx8NmJLK0I5PSBML7k0GQz7wzAozG4wmM96S2nYBmHZBaHgZm7hJh6kWo9MyxgqZWI1jMARkuHa-Hk1Hm5FQfjlzFkP72HSCdhnAwEDZQWr6pAANY6AD8LGoEhsADEILQxrzFRAb7JFCoNCwgA Frequency Detector]

To convert the frequency of a musical signal to a voltage, we can use this relative simple frequency detector circuit. Note that the output is linear in frequency, so it won't match the 1V/oct input of an analog synthesizer. That means pitches will be out of tune. Their might be ways to remedy this by using a logarithmic amplifier instead of the linear amplifier in the schematic. This is shown by the next schematic.

[http://www.falstad.com/circuit/circuitjs.html?ctz=CQAgjCAMB0l3BWEBmAHAJmgdgGzoRmACzICcpkORIC1SJNApgLRhgBQAHiM8glj3SpIPMoKwDq6amABqAegDyAYwAuAHQDOAMwBOjAI4BXRgDtlATy0ATRqsZqA9rvYBDceh7CeYHCObeqOBIrEhg8PBQ0KSoWDFYyFioCMiQRHA4UfHkWPio6URgqDgQ4RHsAO4ePkTUzOi5PKSZkJU+fjV1vv7erVX1jay17f7E1K1gpHW1QcxUPOn+8yLargA2moxR8AjsAEo8CGCec3UIpCfL4CCLIJhI91BRu8oLRLPzzEeX49sREMwsNAqJBcmA0KgLul0GAWMc-hxXvVUB86kJZr4njAIpByHj8QTyFlYjk8gUiiUEewAOaCFHtOlBETM9i6UQIH6MnhXMpwNrI1HVU5Qfl8Tm8DlNFpcBaNeG8NDBG7gTwAW0cpkcmlUrgARmtGFp5FoNYbNJoABaOVTsdLIN5Bd6idAiNieV3oAD6qE9kE9nFQqXBnoQvugYE9rE9XrA0Hwvs9x09yDDkHjrTt3OkN1mRGa4HhIhw3oTAaDKdDMAjUZjccrnuLKex6Zl9VIAgCJ3QOBCcWV8PCAGstAB+NqYoYyTLCvpSzpzgIs9zMfPCifzIJgEJb8A45mwCK1OJEBA4OIEdKkcFPXl8l0CdDZ5hOhonJ3URxGVQABy-NIXTortOyDuiKbJAV4owdIuN7wOw1gLmM4DTkhni2KsRhrDamYQU6IEFqBYBYA2RAJpepBhnglYHluVGRhGMbEcgtqQPaAyeIBSFuk8KZUGRuIUfcqbwO2PZ0TWybJm4BELEEj7TEEm7bmEe48Ni8DhDCBCkHwWAkO2aaweUtLcbwnimZiLJsuuMjyjycFVKZ8wWcMrTWfKqFPkhIjdqks7yfOAXPkyLH2scjpyaeMk+X6fF+uR0bQNRESiae8YSS6UnuScSGfN5dwunyBx5cMnGuU86QgKQWLPK2fgdkU-j8A1Ej9p4ACWpi-ja3DPsMrCoACyD9URjoqiAyifqY9i6PItj2E4Li9fgAJFDlFw+H2MgddNjDUroriqM4rZsKM+TgF0g1tSAayONSri6O1qgWqq7XKForiqt+aztdo7WMEtICtQNnjoMNm3VdtICaMo6xmp932-f9uhaAAFEdWhyEoagAJTsIqmQAGIQPaMiRKwICE-oxhmJY7BAA 1V/Oct frequency detector]

IFD:IAC WiSe22

2023-01-19T15:24:44Z

Clemensw: /* Course Material */

[[:Category:Fachmodul|Fachmodul]] 
'''Introduction to Analog Circuits''' 
''Instructor:'' [[Clemens Wegener]] 
''Credits:'' 6 [[ECTS]], 4 [[SWS]] 
''Capacity:'' max. 12 students 
''Language:'' Deutsch/English by preference 
''Location:'' Marienstr. 5, Electronics Lab R102 
''First Meeting:'' '''Thursday, 2022/10/20, 9:15 am - 12:30 pm'''

==Description==
We will find out about technical foundations of electronics with examples of circuits for analog synthesizers. Starting from discussing simple components, working through some theoretical background, we will start to understand more complex circuits like voltage controlled filters and oscillators. In the final part of the course we think of controling analog circuits with analog sensors. Each student should think of an experimental interface concept and build it.

[https://vimeo.com/461740643 intro video of 2020]

==Admission requirements==
No knowledge in electronics is required. You should, however, bring quite an amount of curiosity to follow the course. Please send a motivational letter to clemens.wegener (at) uni-weimar (dot)de. For buying components, we need a little budget of 20-40€. Of course you can keep your manufactured works.
Up to now, additional private soldering tools are needed, because Covid-19 obligations prevent the use of our workshops. However, these obligations might change over time. For up-to-date information please write to clemens.wegener (at) uni-weimar (dot)de.

==Evaluation==
Successful completion of the course is dependent on regular attendance, active participation, completion of assignments, delivery of a relevant semester prototype and documentation. Please refer to the [[/EvaluationIACWS22 |Evaluation Rubric]] for more details.

==Eligible participants==
Qualified BA Medienkunst/-gestaltung, BA Media Art and Design 

==Syllabus (subject to change)==
* Coming soon

==Course Material==
* [[/sound synthesis/]]
* [[/introduction to electronics/]]
* [[/tasks/]]
* [[/sensors and interface schematics/]]

==Further Reading==
* Otto's DIY Cookbook:
https://github.com/intechstudio/ottosdiy/blob/master/Cookbook/Vol.%201/Otto's%20DIY%20-%20Cookbook%20(Vol.%201).pdf
* DIY Synth Series
https://www.allaboutcircuits.com/projects/diy-synth-series-vco/

== links ==
[https://vcvrack.com/ VCVRack Modular Software Synthesizer]
==Students Project Documentation==
For this semester's project please look
[[/results/ | at the results page!]]

[[Category:WS22]] [[Category:Clemens Wegener]] [[Category:Fachmodul]]

IFD:IAC WiSe22

2023-01-19T15:24:14Z

Clemensw: /* Course Material */

[[:Category:Fachmodul|Fachmodul]] 
'''Introduction to Analog Circuits''' 
''Instructor:'' [[Clemens Wegener]] 
''Credits:'' 6 [[ECTS]], 4 [[SWS]] 
''Capacity:'' max. 12 students 
''Language:'' Deutsch/English by preference 
''Location:'' Marienstr. 5, Electronics Lab R102 
''First Meeting:'' '''Thursday, 2022/10/20, 9:15 am - 12:30 pm'''

==Description==
We will find out about technical foundations of electronics with examples of circuits for analog synthesizers. Starting from discussing simple components, working through some theoretical background, we will start to understand more complex circuits like voltage controlled filters and oscillators. In the final part of the course we think of controling analog circuits with analog sensors. Each student should think of an experimental interface concept and build it.

[https://vimeo.com/461740643 intro video of 2020]

==Admission requirements==
No knowledge in electronics is required. You should, however, bring quite an amount of curiosity to follow the course. Please send a motivational letter to clemens.wegener (at) uni-weimar (dot)de. For buying components, we need a little budget of 20-40€. Of course you can keep your manufactured works.
Up to now, additional private soldering tools are needed, because Covid-19 obligations prevent the use of our workshops. However, these obligations might change over time. For up-to-date information please write to clemens.wegener (at) uni-weimar (dot)de.

==Evaluation==
Successful completion of the course is dependent on regular attendance, active participation, completion of assignments, delivery of a relevant semester prototype and documentation. Please refer to the [[/EvaluationIACWS22 |Evaluation Rubric]] for more details.

==Eligible participants==
Qualified BA Medienkunst/-gestaltung, BA Media Art and Design 

==Syllabus (subject to change)==
* Coming soon

==Course Material==
* [[/sound synthesis/]]
* [[/introduction to electronics/]]
* [[/tasks/]]
* [[/sensors/interface schematics/]]

==Further Reading==
* Otto's DIY Cookbook:
https://github.com/intechstudio/ottosdiy/blob/master/Cookbook/Vol.%201/Otto's%20DIY%20-%20Cookbook%20(Vol.%201).pdf
* DIY Synth Series
https://www.allaboutcircuits.com/projects/diy-synth-series-vco/

== links ==
[https://vcvrack.com/ VCVRack Modular Software Synthesizer]
==Students Project Documentation==
For this semester's project please look
[[/results/ | at the results page!]]

[[Category:WS22]] [[Category:Clemens Wegener]] [[Category:Fachmodul]]

IFD:Analog Circuits and Interfaces/interface schematics

2023-01-19T15:22:58Z

2023-01-19T13:29:56Z

Clemensw:

IFD:Analog Circuits and Interfaces/interface schematics

2023-01-19T13:29:41Z

Clemensw: