Practical making of prototypesof electronic circuits

University teachers: Vidmar Matjaž
Number of credits: 4

Description of the subject

Conditions for work or study:

Completion of all the requirements for the first year of a bachelor's degree in any science or engineering subject involving mathematics. Exceptionally, current first-year students may be allowed to join if they already have a grade of 9 or 10 in Mathematics 1 (or equivalent).

Content:

A rough breakdown of the content:

• Overview of elements, labelling, properties,
• An overview of how printed circuit boards are made,
• The process of making a printed circuit board by toner transfer,
• Overview of soldering processes for printed circuit board components,
• The process of soldering a printed material using a hand soldering iron,
• Electromagnetic interference,
• Enclosures and encapsulations,
• Practical work: making an IR remote (putting theory into practice)
• Individual work: making a device of your choice independently in a form of a seminar

Detailed breakdown of content:

The theoretical part:

1. Basic circuit building blocks, overview of manufacturing technologies, performance characteristics, labelling, pitfalls in ordering components
2. PCB design software
3. Printed circuit board design processes.
4. Drawing a scheme, designing a circuit.
5. Drawing printed circuit boards, selecting eyelets for manual/machine soldering and drilling.
6. File formats and film preparation for different production processes.
7. Positive photographic process, exposure and development.
8. Direct toner transfer with laminator, temperature and other parameters.
9. Printed circuit board etching chemistry: Fe2O3, HCl+H2O2, (NH4)2S2O8 and Na2S2O8.
10. Practical toner transfer on a single-sided printed circuit board.
11. Retouching of defects on the photo varnish or toner, or direct hand-drawing.
12. Practical etching of single-sided printed circuit boards with HCl+H2O2 and with Na2S2O8.
13. Microscopic inspection of an eroded circuit, effect of undercutting.
14. Removal of photo varnish/toner, trimming and drilling of printed circuit boards.
15. Solder alloys, tin and lead, eutectic, additives.
16. Different fluxes for soldering: stearic, rosin.
17. Hydrochloric acid, cinol paste, water-soluble fluxes.
18. Soldering process, melting point and wetting of workpieces.
19. Soldering iron designs, tip types and temperature control.
20. A demonstration of how to tin a printed circuit board.
21. Practical circuit board tinning of an IR remote.
22. Assembling devices by soldering, correct soldering of SMD components.
23. Removing excess solder with a braid and a pump.
24. Amplification and frequency limit of modern building blocks, unwanted couplings.
25. Low-frequency electric field harnessing, electrostatics.
26. Low-frequency magnetic field coupling, example cathode ray tube in an oscilloscope.
27. Radiated electromagnetic field occultation, penetration depth.
28. High-frequency shielded inductors, MF transformers.
29. Soldered brass housings for internal cladding.
30. Using ferrite beads to damp unwanted resonances.
31. Use of ferrite rings to attenuate co-phase disturbances.
32. Capacitors for soldering and screwing, types of ceramics.
33. Microwave circuit enclosure resonances, absorber and surface waves.
34. Electromagnetic compatibility with other devices.
35. Aluminium outer housings, sheet metal selection, sheet metal drawing.

Practical part:

1. Practical soldering of the IR remote control components.
2. Testing the IR remote's circuits, setting the transmitter frequency.
3. Correcting soldering errors.
4. Replacement of incorrectly installed and damaged building blocks.
5. Practical cutting of aluminium sheet for the IR remote transmitter.
6. Transferring a drawing of the IR remote control housing onto a sheet of metal using a laminator.
7. Practical drilling of the various holes and openings of the IR remote housing.
8. Practical trimming of sheet metal to the marks of the drawing of the remote control housing.
9. Practical bending of the aluminium sheet of the rangefinder housing.
10. Assembling the housing and installing the IR remote transmitter.
11. Practical work with a hot air soldering station.

Seminar:

1. Choosing a topic
2. Design of the device
3. Making a printed circuit board
4. Assembling an SMD printed circuit board
5. Installation in the housing
6. Presentation of the work to the other participants.

Objectives:

Ability to independently prototype electronic circuits with SMD building blocks on a printed circuit board, learning how to use the appropriate tools for the job (soldering iron, laminator, paus paper, flux). Learning how to properly handle (own) tools for the job. Testing the finished product, detecting and correcting errors.

Competences (vocationally specific):

• Knowledge of different ways of prototyping printed circuit boards
• Know how to efficiently hand solder SMD components
• Rapid prototyping of electronic circuits as a design step

Knowledge and understanding of:

• Prototyping printed circuit boards
• Reliable manual soldering
• Assembling SMD circuits
• Printed circuit board fault finding and construction
• Housing and cladding

Resources

Exercise manual in digital format, freely available to participants 2

The literature is available to participants via an online classroom or website.

http://antena.fe.uni-lj.si/literatura/VajeOK/Spajkanje/Spajkanje.pdf

http://antena.fe.uni-lj.si/literatura/VajeOK/IRRTX/prirocnik/IRdaljinec.pdf

Studies on which the course is based

• 0 year - cycle - Extracurricular activities