An electronics lab report template, with a worked example
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This page is a template for an electronics lab report. It works for a circuits lab, a digital logic lab or a microcontroller lab. Each section below says what to write and what to leave out.
The circuit above is the worked example: a 555 timer blinking at a few hundred hertz, with a scope and a multimeter on it. We use it to fill in every section of the report, so you can see what a good one looks like.
Your course may have its own format. If it does, follow it. Most formats ask for the same things in a slightly different order.
Aim
One or two sentences. Say what you will build and what you will measure. Example: "To build a 555 astable multivibrator and measure its frequency and duty cycle, and to compare them with the values from the formula."
Apparatus or components
List every part with its value. Example: one NE555 timer, R1 = 10 k, R2 = 10 k, C = 100 nF, a 5 V supply, a breadboard, an oscilloscope and a multimeter.
If you did the lab in a simulator, say so, and name it. It is honest, and it tells the reader why your parts have exact values.
Theory
Give the formula you use, and say where each symbol comes from. Keep it short. The reader wants the idea you are testing, not a copy of the textbook.
Example: the capacitor charges through R1 and R2 and discharges through R2 alone. So the high time is 0.693 times (R1 + R2) times C, and the low time is 0.693 times R2 times C.
Circuit diagram
Draw it neatly and label every part and every value. Mark where each instrument is connected.
In Mokxi, open Export and press PNG or SVG. You get a clean drawing of the circuit you built, not a screenshot. On the free plan, the file has a small badge in the corner. Ask your teacher if a drawing from a simulator is allowed in your report.
Procedure
Number the steps. Write them in the past tense, and say what you did, not what the handout said. Example: "1. The circuit was built on the breadboard. 2. Channel 1 of the scope was connected to pin 3, and channel 2 to the timing capacitor. 3. The frequency and duty cycle were read from the scope."
Observations and calculations
Put the numbers in a table. Give each column a unit. Show one full calculation and then give the rest as results.
Example: high time = 0.693 x 20 k x 100 nF = 1.386 ms. Low time = 0.693 x 10 k x 100 nF = 0.693 ms. The period is 2.079 ms, so the frequency is about 481 Hz. The duty cycle is 1.386 divided by 2.079, about 67 percent.
Then write what you measured next to each predicted value. The scope strip in Mokxi reads the frequency and the duty cycle, and the meter reads the average voltage of the output.
For a microcontroller lab, print your readings with Serial.println and open the Plot tab. Its CSV button downloads every point it drew, one row at a time, so you can make the graph in a spreadsheet.
Result
One or two sentences with the final numbers. Example: "The measured frequency was close to the 481 Hz from the formula, and the duty cycle was about 67 percent." Use the number you actually read.
Discussion and sources of error
This is the section that shows you understood the lab. Explain why the measured value is not exactly the predicted one.
Good reasons: the part values have a tolerance, the meter has an input resistance that loads the circuit, the scope reading is rounded, and a capacitor takes time to settle. Name the one that fits your numbers.
A weak reason: "human error." Say which human error, and how it would change the number.
Then answer one "what if" question. What happens to the frequency if C doubles? Change it in the simulator and check your answer.
References
List the datasheet, the textbook and any web page you used. Give the title, the author or company, and the date you read it. For the 555, the manufacturer’s datasheet is the best source for the timing formula.
If you used code or a circuit from a tutorial, say so and give the link. Changing a copied sketch is fine. Hiding where it came from is not.
Common mistakes
Numbers with no units. 481 means nothing, 481 Hz means something.
Copying the theory from a website. Your teacher has read that website.
A result that only says "the experiment was successful." Give the numbers.
A graph with no axis labels. Label both axes and give the units.
Questions
Can I use a simulator for my lab report?
That is your teacher’s choice. Many teachers accept it for practice or remote labs. Some ask for real hardware. If you use Mokxi, say so in the apparatus list.
How do I get my data out of Mokxi?
Print the values to the serial monitor, open the Plot tab and press CSV. The file has every point that was plotted. You can also read values off the scope and the meter.
Can my teacher see the circuit I built?
Yes, if you share it. Save the project, open Share and copy the link. If your teacher runs a class on Mokxi, you can submit it there instead.
How long should a lab report be?
As long as it needs to be, and no longer. Many reports for one experiment fit in a few pages. Your course rules come first.
Does this work for a digital logic lab?
Yes. Replace the scope readings with a truth table: one row for each input combination, with the output you observed.
Keep going
Build this for real
Open the editor, change a value and watch the number move with it. Nothing to install, and no account needed.