Source: https://mokxi.com/teachers/plans/measurement-and-instruments Updated: 2026-11-11 Lesson plan # Measurement and instruments lesson plan How far to trust a reading: resolution and accuracy, meter loading, bandwidth and the x10 probe, triggering, counters, bus decoding, and an error budget for a real gauge. 4 chapters, 7 lessons, about 6 hours, on the Arduino Uno R3. Every lesson runs in the browser, with nothing to install. Start a class from this course The unit ## Objectives and materials ### By the end, students can - What the digits mean, and what the meter does to the circuit. - Bandwidth, the x10 probe and a trigger you write yourself. - Frequency, duty and the bytes on a bus. - An error budget for a battery gauge, then calibrate it. ### Materials for the whole unit - 74HC595 shift register - Arduino Uno R3 - Bench power supply - Capacitor x 3 - Frequency counter - Full-size breadboard - Function generator x 2 - I/O expander, PCF8574 - Logic analyzer, four channels - Multimeter x 2 - NE555 timer - Oscilloscope - Potentiometer - Resistor x 2 Every part is already on the simulator’s bench, so there is nothing to buy or hand out. The counts are the most any one lesson uses, if you build it on real breadboards too. Chapter 1. About 1 h 30 min ## The meter, honestly What the digits mean, and what the meter does to the circuit. Lesson | Time | What students do Accuracy and resolution A bench meter and an Uno read the same knob. Counts, digits and the 4.88 mV step a 10-bit converter cannot see inside, and why "how fine" and "how right" are different questions. | 45 min - Two voltmeters, one wire - The Uno's answer - Resolution: the smallest step you can see - Accuracy is a different question - Quiz: predict the count - Quick check Meter loading Two 1 megohm resistors should halve 5 V. The meter says otherwise, because the meter is a 10 megohm resistor in the circuit. Predict the error, prove it, and learn when to stop worrying about it. | 45 min - Predict, then measure - The meter is a resistor too - Low impedance hides it - Two meters load twice - Quiz: predict the 100 k divider - Quick check ### Materials - Arduino Uno R3 - Full-size breadboard - Multimeter x 2 - Potentiometer - Resistor x 2 ### Check for understanding Each student finishes "Meter loading" on their own, without opening the hints. The simulator checks 6 of its 6 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Quick check". Chapter 2. About 1 h 50 min ## The scope Bandwidth, the x10 probe and a trigger you write yourself. Lesson | Time | What students do Probes and bandwidth Every instrument input is a low-pass filter. Find the corner of one with two AC meters, then build a x10 probe by hand and compensate it the way you tune a real one on the bench. | 55 min - Every input is a low-pass - Find the corner - Past the corner - Why x10 probes exist - Over-compensate it - Compensate it - Quick check Triggering Why a scope trace stands still: a level and a slope. Set them on the scope, then write a trigger in code (slope, level and auto mode) and watch it behave exactly like the front panel. | 55 min - A trace that stands still - Trigger out - Level and slope on the scope - Code the slope - Move the level - Auto mode - Quick check ### Materials - Arduino Uno R3 - Capacitor x 3 - Full-size breadboard - Function generator x 2 - Multimeter x 2 - Oscilloscope - Resistor x 2 ### Check for understanding Each student finishes "Triggering" on their own, without opening the hints. The simulator checks 7 of its 7 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Quick check". Chapter 3. About 1 h 40 min ## Counting and decoding Frequency, duty and the bytes on a bus. Lesson | Time | What students do Frequency counters Count a 555 two ways, with a frequency counter and with a meter. Gate time and the last digit, duty cycle, and predicting a new frequency from the parts before you measure it. | 45 min - Clip on and count - Two instruments, one answer - Gate time and the last digit - Duty cycle - Change the timing, predict the count - Quiz: predict frequency and duty Logic analyzers One analyzer, two buses: decode SPI into a shift register, then move the probes and decode I2C into an expander, including the NACK of a chip that is not there. | 55 min - Ready on the wire - Decode SPI - Predict the outputs - Move the probes to I2C - An I2C write, decoded - A NACK - Quick check ### Materials - 74HC595 shift register - Arduino Uno R3 - Capacitor - Frequency counter - Full-size breadboard - I/O expander, PCF8574 - Logic analyzer, four channels - Multimeter - NE555 timer - Resistor x 2 ### Check for understanding Each student finishes "Logic analyzers" on their own, without opening the hints. The simulator checks 7 of its 7 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Quick check". Chapter 4. About 1 h ## Boss An error budget for a battery gauge, then calibrate it. Lesson | Time | What students do Boss: an error budget A battery gauge reads 11.961 V on a 12.000 V supply. Find every millivolt: meter loading, resolution, resistor tolerance and the reference, then calibrate it and write the budget. | 60 min - The job - Item 1: the meter - Take the meter off - Item 2: resolution, item 3: tolerance - Quiz: predict the charging voltage - Item 4: the reference - Calibrate it - Write the budget ### Materials - Arduino Uno R3 - Bench power supply - Full-size breadboard - Multimeter - Resistor x 2 ### Check for understanding Each student finishes "Boss: an error budget" on their own, without opening the hints. The simulator checks 8 of its 8 steps as they go. Then ask each one to explain, in a sentence or two, the last thing it asked of them: "Write the budget". Your class ## Teach this unit as a class Start a class from this course and its 7 lessons are assigned in one go, in order. Students join with a six-character code or printed login cards, and each one’s work comes back to you. The class tools are free for 30 days for one class of up to 20 students, with no card. The lessons themselves are free either way. Start a class from this course See the demo class More units ## Other lesson plans Electronics basics 20 lessons, about 10 h. Embedded on the Arduino Uno 16 lessons, about 12 h. Embedded on the ESP32-C3 13 lessons, about 11 h. Embedded on the Raspberry Pi Pico 7 lessons, about 6 h. Build your own fight stick 5 lessons, about 4 h. Embedded on the STM32F411 6 lessons, about 6 h. C++ on a board 13 lessons, about 10 h. Digital logic and memory 4 lessons, about 4 h. Interactive devices on the Uno 9 lessons, about 8 h. From gates to a computer 23 lessons, about 16 h. Build a claw machine 8 lessons, about 6 h. Every unit All the courses as ready-made units, on the teachers page.