ICS2O-E: DER PROJECTS

There are no quizzes, tests, or exams in our ACES program. Put another way, you are NEVER put into the position of having a dramatically limited amount of time to demonstrate the skills you have acquired. You can invest as much (or as little) time into your reports as you choose. In return for being granted complete control over the depth and quality of your submissions I can place a premium on detail, precision, and the pursuit of perfection. So, my advice to you if you want to become exceptional is to follow the written and oral instructions carefully and, beyond the required elements of each report, demonstrate tasteful and appropriate creativity and imagination to distinguish yourself from the mediocre. Good luck and, remember, the race is long but it's over quickly.


Reports. Required Elements

If you do not submit your report by the deadline specified, you receive a mark of 0. This is done as a favour to you to help you appreciate that the real world will dismiss you if you can not demonstrate responsibility and accountability. You are to archive ALL of your reports in the single Word document, DER.docx. The first page is your Title page, followed by a multi-page Table of Contents, after which your reports begin. EACH report will start at the top of the next new page and, unless otherwise specified, consist of the following sections, in the order listed,

Purpose

Reference

Procedure

Media

Reflection


The vast majority of us can tell the difference between quality and rubbish in an instant. As a young scholar you have to decide what your name will stand for. It should matter very little whether you enjoy a task or not; if you're going to attach your name to something it is a direct reflection of who you are.


 

Project 1.4 Counting Circuit

This culminating activity provides a simple introduction to fundamental capabilities of many digital devices: that of Oscillation, Counting and Display. There are a number of stages or subcircuits in this system and your DER will clearly present the role played by each.

Start your DER with a big picture Theory section, written in your own words that mentions, generally, the input to the system, the generation of a clock signal consisting of pulses having both a duration and a frequency, culminating in the presentation of the pulse count on the display device. This would also be an ideal place to present a detailed, margin-to-margin, (Fritzing or TinkerCAD) breadboard or (organized) schematic view, to introduce your readers to the full prototype you are about to describe and discuss in multiple pages that follow.

A Note on Graphics. Graphics should support the text they are illuminating. Poorly composed photos, sloppy and inconsistent choices for diagrams like pinouts and schematics work against you as they can confuse your readers and leave them with a sense that the author doesn't care about his presentation so why should they?

Follow the Theory Section with the eight subsections (A-H) described below. For the first section, Analog Input, include, as a graphic, that part of the schematic that it pertains to. The next five sections (B-F) subsections should include a Reference Section that includes the respective live hyperlink appearing below:

Following the Reference Subsection within each of the five areas, include a Purpose section (this one could go before the Reference Section) describing in detail, how each stage contributes to the sequence. Be sure to clearly present the input, processing, and output of each stage, supported by informative, attractive, and well-formatted graphics.

Following the final subsections include Media (captioned photos and video) and Reflection sections.

A. Analog Input

B. NAND Gate Oscillator (4011)

C. Decade Counter (4017)

D. Decimal Counting Binary Up/Down Counter (4510)

E. Binary Counting Decimal Decoder (4511)

F. Seven-Segment Display

G. A Counting Circuit PCB

Quantity Description
1 Custom PCB
1 0.1 μF Disk Capacitor
1 100 μF Electrolytic Capacitor
1 14-pin IC Socket
3 16-pin IC Sockets
2 1 kΩ (Isolated) Resistor Network
1 2-pos 2.54 mm Term Block
Once the breadboard prototype media has been obtained for your DER (photos and video), ACES are to convert their prototype to a more permanent device. A custom printed circuit board was designed and manufactured expressly for the use by Jr. ACES for this purpose. Interested ACES should present their working prototype to Mr. D'Arcy at least TWO days prior to the DER due date in order to receive their PCB and supplemental parts. Receipt of such a board comes with the expectation that components will be soldered, the circuit tested, and summarized in text, photos, and video as part of the DER summary for this Counting Circuit project.

H. A Counting Circuit PCB Case

Congratulations on reaching the final stage (8) of our marathon Counting Circuit project! Students that have successfully soldered their PCBs that demonstrate forward (and backwards) counting on the seven-segment display are invited to present their circuit to Mr. D. to receive a custom case designed and printed in the DES by J. Dolgin (ACES '20) into which their device can be mounted. A similar two-colour case was printed on the Ultimaker 3 in 2018 by K. Fiset-Algarvio (ACES '19). Click the image below to view a short time-lapse video of the case being printed,

Power for the device is sourced from a 9V battery inside a compartment within the interior of the case. The leads of a battery snap can be soldered to the correct pads in lieu of an external DC Jack. Be sure to place electrical tape across the battery to insulate it from the bottom of your PCB to prevent the possibility of shorting. Finally, screw the assembly together and fully test, prior to capturing the final frames of your project video.

Finally, be sure to address ALL issues from previous submissions and update your Table of Contents before attaching DER.docx to an email to handin under the Subject Line: A Counting Circuit


Project 1.? ACES Christmas Tree for Fall 2023!

In addition to recently-introduced digital logic gates, the CMOS family offers a wide range of specialized ICs. One such terrific chip in the counter category is the 4060, that takes a clock signal as input and offers a variety of frequency divisions on its many output pins. The suggestion on the Electronics' Club's site that this could be put to good use in creating a Christmas decoration was too compelling to resist! So, here we are...

4060 14-bit (÷16,384) ripple counter with internal oscillator 4060 RC Oscillator

Good References:

Schematic

Task (Prototype)

  1. Develop a breadbord prototype of the circuit above.
  2. When completed be sure to take planty of photos and video for your Report.
  3. Finally, sho Mr. D. your working version to receive your ACES Christmas Tree PCB.

 

Task (Device)

It's time to solder up the final device that you could include in your holiday celebrations. This task comes in three (qualifying) stages because the cost of the parts are free to you, but expensive for me. You provide the 16 pin chip seat and the 4060, I provide the first round of supplemental components that includes,

At this stage you must confirm the functioning of your tree by applying 9V to the positive and negative power pads. Any soldering issues must be resolved prior to demnstrating it to Mr. D. to receive the second round of supplemental parts.

The second round of parts include,

Seat the tree on a 9V battery to confirm functionality. Next, remove the battery and plug in 9V to the power jack to confirm. Demonstrate to Mr. D.

The final part is the star diffuser and aluminum stand, designed by S. Appleyard (ACES '23) and milled by M. Elia (ACES '15) of Argon Prototypes.


Project 1.3 2-Bit Adder

Recently-completed class sessions have introduced you to digital logic gates. These are the computer's primary operators in much the same way as addition and multiplication are humans' primary arithmetic operators. One of many useful circuits involving logic gates are circuits that allow computers to perform addition of binary (base 2) numbers.

Background: Half- and Full-Adder Circuits

The graphic to the right is meant to reveal how the computer 'sees' the addition of 74 and 7, organized as 8-bit binary numbers. Similar to humans, the computer proceeds from right-to-left, adding pairs of binary numbers (0 and 1). For the first addition (green) there is no 'carry in' number from a previous addition. This requires a circuit known as the Half-Adder. For each of the remaining seven additions (red), the computer must add the two binary operands (A and B) but must also add in the binary number carried from the previous addition (C). A circuit that performs this is referred to as a Full-Adder.

Jr. ACES are not expected to have come up with the circuit designs for the Half- and Full-Adder circuits (although many of you likely could), but a strong grasp of why they work, and the correct outcomes they produce, provide deep mental satisfaction. To this end, you are encouraged to spend time interacting with the relevant combinational circuit examples provided as Falstad simulations in the table below.

Half-Adder Full-Adder
Falstad Simulation: https://tinyurl.com/yehzn8gc Falstad Simulation: https://tinyurl.com/ydomt5mp

Task. The 2-Bit Adder Circuit

  1. With the Half- and Full-Adder circuits above as a foundation, a breadboard prototype capable of the addition of a pair of 2-bit operands can be achieved.
  2. The graphic to the right is the goal of this circuit. A Half-Adder circuit is required to produce the sum of A0 and B0 (green), together with a carry bit to merge into a Full-Adder circuit to achieve the sum of A1 and B1 (red) with a carry bit, C2.
  3. The schematic for this circuit appears below.
  4. An RSGC ACES' Falstad simulation can be explored by following this link: https://tinyurl.com/2ymqmqzj.
  5. Breadboard prototype parts will include 4 push buttons (or slide switches) for inputs A and B input pairs, three LEDs for outputs, and the required CMOS ICs as the processor that integrates both a Half- and Full-Adder as the circuit below suggests.
  6. On Wednesday November 30 ALL students will be supplied with the components required to assemble a permanent 2-Bit Adder device. This includes the 2-Bit Adder PCB Version 1, a 3D printed case, and power jack. NOTE: Since the Version 1 PCB is not fully-functional you will simply dry-fit three 14-pin IC sockets into the PCB before you take your photo in the case. Instructions will be provided in class on how to prepare your power jack and case.
  7. Enhanced Procedure and Media Sections. Within both sections, include a subsection that describes the process and photos of the Device assembly outlined in Step 6. Within the Procedure's subsection adapt a supplementary parts table as I've provided in this Word document that is consistent with your previous preferred column organization and shading theme.
  8. Superior photos and video footage of your breadboard prototype (and encased PCB) are essential. When Version 2 of the PCB arrives in December you will be given the supplemental parts to solder the device and replace DER photos with the functioning ones.
  9. Using the DER returned to you that has since been edited and corrected, and taking into account the personal and general feedback comments you have been provided with, start this report on first new page, after your Project 1.1 The Capacitor Visualizer report. Add the new Project name in Heading 1 Style and complete sections under the subheadings: Purpose, Reference, Procedure, Media, and Reflection. Text is developed in accordance with the recommendations for Technical Writing and reflective of your much-improved formatting abilities. Graphic manipulation is undertaken according to the specifications laid out in the Design Engineering Report General Guidelines.
  10. Students should note that the mark you receive for this submission will be based on the clarity of your circuit presentations and quality of your DER based on your response to the expectations, feedback, and support previously provided you.
  11. Attach your DER to an email to handin with the Subject: The 2-Bit Adder by Saturday December 3 at midnight.


Project 1.? 1-Bit Magnitude Comparator

The vitality of our DES courses can be attributed to the achievemennts of the ACES that have preceded you. It is through their curiosity and commitment to their futures that we all benefit. It was J. Goodwin's (ACES' 22) 8-bit computer Medium ISP that inspired me to present this combinational logic circuit project to prepare you for what lies ahead.

Modern digital technology is built on the foundation of Logic. On the back of a small set of logical operators (AND, OR, NOT, etc.) extraordinarily complex systems are constructed that enable all the devices we depend on. To begin your familiarity with these fundamental blocks you are asked to provide a circuit demonstration of a concept familiar to you: the relative magnitude (order) of (the two binary) digits: 0 and 1.

References

Task (Have your phone's camera available throughout the entire week to capture meaningful media for your Report)

  1. Develop a breadboard prototype of the combinational circuit above right. Here's a general layout you are encouraged to follow (simply because I have to figure our 24 builds)

  2. Two correctly conditioned slide switches are to be used for the inputs A and B.
  3. Since the three outcomes are mutually exclusive, your are to employ your COMMON CATHODE RGB LED as the sole indicator. Show RED for A<B, GREEN for A=B, and BLUE for A>B. Note: I recommend using no less than a 1 kΩ resistor (even going as high as 10 kΩ) as these can be blindingly bright!
  4. On the custom PCB you will eventually be provided with, I have used only red and green surface mount LEDs as indicators in pace of the RGB LED.
  5. For your Report, in addition to all the standard sections (Purpose, Reference, Theory, Procedure, Media, Reflection), you will include the following,
  6. Examine the circuit closely. It would not be obvious to many at first glance why is works but, if you push yourself to think about it, it becomes obvious and you should explain it (clearly), in your Procedure Section.
  7. In your Report, observe and comment on the behaviour of your circuit if the slide switches are simply removed from a functional circuit.
  8. Your final device will be powered with (approximately) 5 V. For the final assembly stage of the project you will be provided with 3 AA batteries and the supporting components that appear to the right. Once this is complete, four M3 screws and hex standoffs will be provided to serve as legs to elevate the comparator off the surface of your table. Note. For those that are contiuning on to our Grade 11 course, you are encouraged to imagine and the manuy optins there re for mounting PCBs if both a functional and esthetic case or stand. This is why I provide you with these simple additional fasteners; to get you thinking about the elegant finish and polish of your projects.
  9. MS Excel offers the basic logic function (AND, OR, and NOT). See if you an duplicate the table below using these Excel logic functions that summarizes the 1-Bit Magnitude Comparator combinational circuit in this project. Remember, CTRL+` can be used to toggle the Excel views from Normal to Function and back again. A discussion of this would provide an enriched enhancement to your Report.

     


Project 1.2 Joule Thief (aka Blocking Oscillator)

Wireless (inductive) phone chargers are common these days. Advertisements for many new cars squeeze in an image of a deck onto which you place your phone for charging while cable-free. This project begins to look at the concept behind this technology by bringing the application closer to home in a fundamental circuit.

Commercial Phone Charger Field of Magnetic Lines of Flux from a Current Through a Coil

It's maddening (not to mention environmentally unfriendly) that 1.5V AA or AAA batteries are as good as useless in your TV remote even when when they still read 1.1V. It's time to get even with those stubborn cells by mining every bit of potential they've got left in them before they head to Home Depot or Home Hardware for a proper recycling. Other names for this circuit can be found under Blocking Oscillator, Vampire Torch, Vampire Flashlight, and DC Boost Converter. Researching any of these phrases could give some of you some great ideas for your ISP.

Task 1. Look around your home for your stash of, so-called, 'spent' (0.5V-1.1V) AA batteries. Recall that fresh out of their package, they delivered about 1.6V. Mark them as USED and put one or two in your toolkit as you'll use them in this project.

By now you are aware that voltage requirements for LEDs correspond closely with their relative position on the visible spectrum with RED requiring roughly 1.7V to BLUE and BRIGHT WHITE pushing 2.8V-3.1V.

Task 2. Although it's a bit of a lost cause, see if you can light up any LED in your kit with one of those 'spent' AA batteries directly.

A review of the datasheet for the clear white LTW-2S3D8 LED pictured you have been provided with indicates, on page 4, that an average forward voltage of 2.8V is required for this lamp to function normally. The purpose of the project is to take a minimal voltage source like a used, 1.5V, AA battery and boost its voltage high enough to light the 2.8V lamp. This is essentially the principle behind the ubiquitous solar garden light! (see links below)

Joule Thief Schematic ACES' Joule Thief PCB (for Keystone #2461)

Research (be sure to undertake these steps prior to completing the required task)

  1. Review a few principles relating electricity and magnetism: ACES' Frame Player: Field Forms
  2. Using a DMM test a fixed resistor for continuity. Explain this result.
  3. Using a DMM test an inductor for continuity, Explain this result.
  4. You should be aware that a Capacitor uses VOLTAGE to store energy whereas an inductor uses CURRENT!
  5. An inductor can also be called a choke? Why is this term appropriate?
  6. A boost converter is a device designed to increase voltage. What similar name is given to a device used to decrease voltage?
  7. Review the four scope traces obtained in the DES of the device you are about to prototype at the 0.6V, 0.7V, 0.8V and 0.9V levels through the Frame Player: Joule Thief. Offer a possible explanation of these wave forms.

Task 3 (Optional, for the Physics-Minded ACE).

Inductor coils are employed throughout the electronics industry to increase and decrease voltage levels and are aptly referred to, generically, as transformers. Unlike the pair of 100 μH axial coils with built-in windings used the PCB version of our Joule Thief above, intrepid ACES that find fundamental physics concepts appealing are encouraged to wind their own coil around a toroid-shpaed ferrite ring to generate the same effect on their breadbaord protytype.

  1. Drop by after school and ask Mr. D. for an enameled ferrite ring.
  2. Go to the wire rack at the back of the DES and cut off 50 cm of two different wire colours of your choice. Use the ruler undernesth to measure them out prior to cutting.
  3. NOTE. The wire is sheathed and the toroid ring is enameled to prevent the bare metals shorting the electromagentic signals.
  4. Watch this video (or any one of hundreds) of the winding technique. Ten to twelve tight, non-overlapping windings should do it. For the really keen ACE, check out this Toroid ring inductance calculator site. Yikes!
  5. TBC...
Toroid Rings from Amazon ACES' Wound Toroid Ferrite Ring

Task 4.
  1. Here is a good explanation for the operating principle of the Joule Thief taken form a comment by C. Mitchell on a YouTube Video, "In the beginning the voltage of the battery is high enough to turn the transistor ON. This allows current to flow through the collector-emitter junction and the magnetic field in the transformer increases and creates a voltage in the base winding that turns the transistor ON more. This continues until the transistor is fully saturated OR the magnetic flux in the core creates SATURATION. At this point the magnetic flux is no longer EXPANDING and the extra voltage and current being passed to the base of the transistor suddenly STOPS and only the originating current into the base is present. This is not enough to keep the transistor turned on FULLY and the magnetic field starts to COLLAPSE. The collapsing magnetic field cuts all the turns on the transformer and produces a voltage in the base that has an opposite polarity to the originating voltage. This turns the transistor FULLY OFF. The transistor effectively COMES OUT OF CIRCUIT and the lead connected to the collector produces a voltage that is opposite in polarity to previously and this means the voltage is HIGHER than the voltage of the battery by a value that can 10v to 20v. This voltage is high enough to illuminate the LED and even 2 or 3 LEDs can be connected to the circuit. But a LED has a characteristic voltage depending on its colour and for a white LED this is 3.2v. The voltage across the LED can never rise higher than this and the output voltage of the transformer is limited to this value and all the energy from the collapsing magnetic field is converted to light by the LED. At the same time the magnetism is cutting the turns of the base winding and producing an output voltage that is negative and keeping the transistor fully turned OFF. When the magnetic field has fully collapsed, the negative base voltage reduces and the battery voltage starts to take over, via the resistor and when it is above 0.6v, the cycle starts again. This process occurs at the rate of about 100,000 cycles per second. Persistence of Vision of your eye means you cannot see the flashing of the LED and it appears to be ON all the time."
  2. Breadboard the schematic of the Joule Thief provided above, left. Be sure to capture media for your DER and video in the process.

Task 4 (Only for the Highly Committed).

This final stage requires an added investment of parts and demands patience, accuracy and commitment. If you are that person, speak to me after school.

  1. Plan out, transfer, and solder your supplemental parts to the Stripboard provided (coils, terminal block)
  2. Connect a 1.5V alkaline battery to the circuit for testing.
  3. If it functions as expected, demonstrate it to Mr. D. to receive the 2-position Terminal Block to solder in, facing outwards.
  4. If it still works, present it to Mr. D. to receive your Keystone #2461 AA battery holder.
  5. Add a supplemntal section to your DER and take a bow.
Fritzing View of Joule Thief (Stripbaord Version) BPS ST1 Stripboard

 

MakeZine: Joule Thief

Good Inductor videos: Still looking

Falstad Simulation: http://tinyurl.com/y3a8pspu

Evil Mad Scientist: Solar Garden Light Talking Electronics: Solar Garden Light

ISP?: Assembling a Joule Thief after winding a Ferrite Core

White LED Drive Circuit


Project 1.? Astable Multivibrator (aka Analog Oscillator)

The Square Wave, a highly orchestrated sequence of alternating high and low durations, is the backbone of modern, digital, communication. The purpose of this project is to introduce you to the transistor and to demonstrate how it can be combined with other familiar analog components to produce an oscillating signal with properties similar to the digital square wave.

Task.

  1. Clean the lens of your phone's camera, as you will be gathering media (photos and videos) throughout this project, from start to finish, in support of your DER project summary due Saturday November 16.
  2. This project will test your organizational abilities as much as your nascent electronics' knowledge and skills. Part of the task includes thinking deeply about what you're doing.
  3. After studying the schematic of the Analog Oscillator below left undertake your prototype (aka, blinker, Astable Multivibrator) on your breadboard. When you are confident the circuit has a chance of functioning, apply 9V power. Debug as necessary and document the results with your phone's camera. You may wish to experiment with the rate at which the LEDs are flashing by adjusting the sizes of the resistors.

  4. Analog Oscillator Schematic PCB: Dry Fit

  5. Once you have obtained your media, you can request the additional parts that include a printed circuit board (PCB) and three terminal blocks. Disassemble your prototype and 'dry fit' the parts on your PCB (above right) in a manner similar to the image to the right (click to enlarge). This is an important step to appreciate the full scope of the task that lies ahead and to avoid the risk of soldering parts incorrectly that can be difficult, or near impossible, to repair.
  6. With your soldering area fully equipped with easy access to the required tools and conscious of the soldering techniques and strategies discussed in class and in this soldering video, you may begin the soldering stage. Remember,
  7. If you have invested care and thought into your efforts, plugging your 9V adapter into a temporary DC Power Jack should yield the desired outcome: a pair of blinking LEDS. If it doesn't function as expected, prepare yourself for the best part: debugging. Seriously, few activities are as satisfying as analyzing and repairing a faulty system. Use the large illuminated magnifying glass to check all your solder joints. Confirm your polarized parts are in the correct way. Use the DMM to to perform continuity, voltage, and integrity inspections. You WILL find the problem without the need to ask for my intervention.
  8. Once everything is as it should, present a working circuit to Mr. D. to get your Power Jack. Assemble it as you did for your Capacitor Visualizer.
  9. Finally, present both for your Analog Oscillator case and screws for final assembly.
  10. DER. Starting on a new page, add the Project name and complete sections under the subheading: Purpose, Reference, Theory, Procedure, Media, and Reflection. Text is developed in accordance with the recommendations for Technical Writing and reflective of your much-improved formatting abilities. Graphic manipulation is undertaken according to the specifications laid out in the Engineering Report General Guidelines.
  11. Attach your DER to an email to handin with the Subject: The Analog Oscillator (aka Astable Multivibrator) by the deadline.

Project 1.? ACES Knight Light (Deluxe)

Below is the objective you're aiming for, in your first formal Design Engineering Report (DER) project. Ambitious? Certainly. RSGC's ACES program combines careful engineering and design elements to emulate a more complete prototype development experience. So, if you listen attentively to class instruction, employ strong organization and time-management skills this week and THNK, THINK, THINK, you will accomplish a goal you will be justifiably proud of. The project description appears below.

  1. Class time has been devoted to the introduction of a number of analog components and provided you with an opportunity to develop a breadboard prototype of the ACES Knight Light circuit outline in the schematic to the right (click to enlarge). Heeding the advice and techniques described, develop a high-quality breadboard of the ACES Knight Light. Be sure to document your build using photos and video captured on your phone for later use in your Report.
  2. Following the detailed instructions and parts provided by Mr. D, prepare your 10 KΩ (panel mount) potentiometer for eventual use in your acrylic stand. Test the integrity of your soldering skills by replacing your blue breadboard trim pot with your panel mount version to confirm the circuit still functions as before.
  3. Having listened and observed attentively to Mr. D's soldering demonstration, and reviewed the excellent soldering video prepared for you by a former ACE (N. Vassos), begin to transfer both YOUR parts and the SUPPLEMNTAL parts provided to you, to your custom ACES Automatic Knight Light PCB. Be sure to examine each solder joint carefully as you go, using the magnifying glass on Mr. D's desk if you need to. Have a DMM handy to confirm continuity and identify unintended shorts between leads every step of the way. Again, the best DERs are from authors who had their phone out capturing photos and video footage of the oldering process.
  4. Finally, solder your panel mount potentiometer to the PCB, making sure the three wires are an approriate length. Attach your 9V battery. Test thoroughly.
  5. When Step 4 is complete, present your assembly to Mr. D. for his review. If everything appears to be in good working order he will provide you with the additional parts required to mount your PCB on the acrylic stand.

DER Task. Your writeup for this first project will include,

  1. Create the Word document, DER.docx that includes a Title page, Table of Contents (ToC) and headers and footers as discussed and developed in class.
  2. Each Project writeup in your ACES career starts on a new page.
  3. For this first project, start a new page after your ToC, be sure the page numbering starts at page (Arabic) 1, and place Project 1.1 ACES Knight Light in Heading 1 Style at the top of the page. Subsections, styled as Heading 2, must include,
    1. Purpose one or two short, well-constructed sentences that underscore the precise concept(s) being highlighted in his project
    2. Reference Include a hyperlink pointing to the URL of this project description and any other online resource(s) you explored with advantage
    3. Theory. Discuss the concept of a voltage divider in general, how it is employed in this circuit, what purpose it serves, and how the entire circuit works.
    4. Procedure You may use the schematic above right as long as it is properly sized or create your own. There are many options for this incldsing:.Digikey's Scheme-It, Fritzing, Falstad, CircuitIO, etc. With specific reference to the Test Point (TP), marked on the schematic with a red dot, explain, using your new vocabulary, how the voltage at the TP influences the function of the 2N3904 NPN transistor. Include a complete, 2-column (asymmteric column widths), 3" wide, background-shaded, right aligned, Parts Table.
    5. Again, your Procedure discussion must be supported with a schematicthat is, 3" wide, right-aligned on the page, and top-aligned with a paragraph.
    6. Media. Insert insanely clear, close range photos (can I distinctly see the colour bands of your resistors?) of your breadboard prototype, the front and back of your soldered PCB and the final masterpiece. Listen to my verbal comments of the best places and techniques for inserting photos into your report. Create a 2-minute video of your circuit with accompanying explanations and annotations of the components. Upload to YouTube within your own personal channel (not RSGC's) and include a full URL link in the Media section. Some of our best videos appear on our ACES' home page carousel. You can't afford to lose this video work.
    7. Reflection this is the only segment written in the first person and includes any comments you have about the concepts, the build process, any challenges you overcame and personal time-management issues you were pleased with or need to address in the future.
  4. Technical writing is done on the present, active voice, NOT presented in the first, second or third person. See these do and don't examples.
  5. Update your Table of Contents.
  6. Submit your DER.docx as an attachment to an email to ACESHandin with the Subject Line: ACES Knight Light

Remember, your text should be developed in accordance with the recommendations for Technical Writing. Good luck.


Project 1.? Capacitor Visualizer

Along with resistors, capacitors belong to a family of components known as passives in that they do not introduce a new source of energy into a circuit. Capacitors serve a number of useful functions in both DC and AC circuits. In completing this project you will strengthen your understanding that the capacitor (in series with a resistor), plays in the timing aspects of analog DC circuitry.

This project takes time to undertake properly, so be patient, and start early.

The schematic, below left, is of a straightforward test circuit that, in my view, best illustrates of the functional behaviour of an electrolytic capacitor in a DC circuit. You are familiar with the concept of a voltage divider from your first project. Looking at the junction (node) between S1, R1 and R2, we introduce the notion of a current divider as the current splits into two branches due to their parallel configuration.

We have discussed the charging of an empty capacitor and the effect this has on the capacitor in terms of its resistance (in AC circuits this property is referred to as reactance). In a DC circuit, a single RC Time Constant, denoted τ, can be expressed simply as,

`τ=R×C`

where τ is measured in seconds, R is measured in Ω, and C is measured in F. Also discussed in class (p. 33) is the expectation that after 5 RC time constants the capacitor is virtually fully charged (5τ~99%). One of the objectives of this project is to observe and confirm the expected results.

Schematic Printed Circuit Board

Task.

  1. To achieve the best results for each of the numerous trials, the capacitor should be fully drained. In the Procedure section of your report, explain how this is achieved in the circuit to the right.
  2. On a breadboard, prototype the circuit above left as neatly as you can using the first pair of resistor-capacitor values in the table below. Connect the longer lead of the bicolor LED to the capacitor and the shorter lead to ground. This ensures the orientation that agrees with the schematic. Note: Be sure to drain the capacitor and measure the voltage with your DMM to be sure. Explain this step in your Procedure and explain any related issues you have in achieving this.
  3. Once connected, hold the momentary button down (for as is required) before releasing it. Note the behaviour of the LEDs in particular, and try to explain what electrical behaviour at work, throughout. Do this a number of times until you feel you understand the principles.
  4. Now, more formally, using the timer on your phone, and through observation, record the approximate charging time for a fully discharged state until your eyes can no longer detect a visible state change in the red LED. A DMM can be used for more accurate results. Perform at least three trials with the first Resistor-Capacitor pair and record the average.
  5. For your DER, you are asked to duplicate the table that appears below. In the third column determine and enter the theoretical (expected) time to fill. In the fourth column, enter your observed result.


  6. Repeat Steps 3 and 4 for each of the remaining 2 RC pairs in the table. Again, perform a number of trials with each pair and record the average.
  7. For your DER summary of this Project, you MUST remember to obtain media of your prototype (both still images and video), before you dismantle it to solder together your completed device on the PCB provided. Be sure to watch the Instructional video, prior to soldering. Finally, demonstrate a WORKING version of your soldered PCB to me by Thursday October 31 to obtain a custom case for your device.
  8. In your DER, be sure to include the required sections listed above. You are to provide your own Fritzing schematic It is up to you to decide the supporting images and graphics that engage your readers and leave them with a solid understanding of the concepts. The table above is large enough to be center-aligned on your page.
  9. Attach your (corrected) DER to an email to handin under the Subject Line: The Capacitor Visualizer by the deadline.

Project 1.1 Voltage H-Bridge (K)night Light

One of the most important skills an Engineer must possess is the ability to communicate, both in spoken word and in written form, in a highly structured format. Developing this skill takes much practice and this is precisely why the Design Engineering Report plays such a crucial role in our program, your mark, and your future.

With the skills gained over the past few classes, you are ready to prepare your first Design Engineering Report (DER) submission. Furthermore, you are required to be familiar with the Guide for Technical Writing and, through practice and regular editing, your sentence structure will improve. Poor grammar and spelling skills detract from your presentation.

The Voltage H-Bridge circuit provides a vivid reflection of the fundamental voltage, current and resistance concepts we explored and analyzed over the first dozen classes. A schematic of the circuit appears to the right. The letter H is clearly visible in the depiction as the crossbar spans two voltage dividers (one variable and the other, fixed).

Task (Basic).
  1. Create the Word document, DER.docx that includes a Title page, Table of Contents and headers and footers as discussed and developed in class.
  2. Each Project writeup in your ACES career starts on a new page.
  3. For this project, start a new page, be sure the page numbering starts at page (Arabic) 1, and place Project 1.? H-Bridge (K)night Light in Heading 1 Style at the top of the page. Subsections, styled as Heading 2, must include,
    1. Purpose one or two short, well-constructed sentences that underscore the precise concept(s) being highlighted in his project
    2. Reference include a hyperlink pointing to the URL of this project description and any other online resource(s) you explored with advantage
    3. Procedure discuss the concept of a voltage divider in general, how it is employed in this circuit, what purpose it serves, and how the entire circuit works. Finally, include a complete, 3" wide, background-shaded, Parts Table, and YOUR unique duplication of the schematic above right, created in Fritzing, 3" wide and right-aligned.
    4. Media formatted and captioned photos and (no more than) 2 minute video uploaded from your personal YouTube channel. By personal, I mean you do NOT use your RSGC email or other credentials to create this channel as your material will disappear after graduation. You can't afford to lose this work.
    5. Reflection this is the only segment written in the first person and includes any comments you have about the concepts, the build process, any challenges you overcame and personal time-management issues you were pleased with or need to address in the future.
  4. Technical writing is done on the present, active voice, NOT presented in the first, second or third person. See these do and don't examples.
  5. Develop your own Fritzing breadboard and schematic images for inclusion in your submission and store them in your images folder. Include them in the Media subsection together with high resolution, well-composed, and formatted photos.
  6. Create a short (1-2 minute) video of your circuit with accompanying explanations and annotations of the components. Upload to YouTube within your own personal channel (not RSGC's) and include a full URL link in the Media section. Some of our best videos appear on our ACES' home page carousel.
  7. Update your Table of Contents.
  8. Attach your Design Engineering Report (DER.docx) to an email to handin with the Subject: Voltage H-Bridge by the required deadline.

Remember, your text should be developed in accordance with the recommendations for Technical Writing.

Additional Task for the Inspired.

Highly-motivated students are encouraged to explore this related circuit based on the concepts of the Voltage H-Bridge.

  1. Examine the schematic to the right. Click to enlarge.
  2. The H-Bridge consists of two voltage dividers spanned by a standard LED.
  3. The voltage divider on the right presents a fixed voltage reference for the cathode lead of the LED.
  4. The voltage divider on the left is variable, through mechanical meads (pot) and optical influence (LDR)
  5. After thinking about why this can apltly be called a (K)night Light, breadboard the circuit and run a few tests. The cap of a Sharpie over the LDR does a good job of blocking the incident light.
  6. Add a summary of this extra circuit to your DE Report.

 


Last Update: 2023 01 03