Contenido

1. Introduction
2. History: how sound learned to measure distance
3. Lesson 0. Gates from transistors: for those who start from scratch
   1. 0.1. The idea: a transistor is a switch
   2. 0.2. Building
   3. 0.3. Check
   4. Lesson 0 paste (Cmd+I)
4. Lesson 1. The CD4013 D flip-flop
   1. 1.1. Idea: remember at a moment
   2. 1.2. Idea: master and slave
   3. 1.3. Idea: weak feedback
   4. 1.4. Idea: divide by 2
   5. 1.5. Build
   6. 1.6. Check
   7. Lesson 1 paste (Cmd+I)
5. Lesson 2. The sweep: CD4017
   1. 2.1. Idea: poll in turn
   2. 2.2. Idea: the Johnson counter
   3. 2.3. Idea: self-correction
   4. 2.4. Idea: clock, inhibit and carry
   5. 2.5. Build
   6. 2.6. Check
   7. Lesson 2 paste (Cmd+I)
6. Lesson 3. Ultrasound and echo: CD4072
   1. 3.1. Idea: an echo is time
   2. 3.2. Idea: in turn and through OR
   3. 3.3. Idea: a 4-input OR at TI
   4. 3.4. Build
   5. 3.5. Check
   6. Lesson 3 paste (Cmd+I)
7. Lesson 4. Centimetres: CD4029
   1. 4.1. Idea: centimetres are clocks
   2. 4.2. Idea: clear before the ping
   3. 4.3. Idea: stop at 99
   4. 4.4. Idea: the synchronizer
   5. 4.5. Idea: ±1 clock
   6. 4.6. Build
   7. 4.7. Check
   8. Lesson 4 paste (Cmd+I)
8. Lesson 5. Zones and bars: CD4585
   1. 5.1. Idea: a zone is the tens
   2. 5.2. Idea: a comparator, most significant first
   3. 5.3. Idea: remember the zone of a sensor
   4. 5.4. Build
   5. 5.5. Check
   6. Lesson 5 paste (Cmd+I)
9. Lesson 6. The nearest and the digits. Calibration
   1. 6.1. Idea: the minimum of a round
   2. 6.2. Idea: a cascade of comparators
   3. 6.3. Idea: the digit latch
   4. 6.4. Idea: calibration
   5. 6.5. Build
   6. 6.6. Check
   7. Lesson 6 paste (Cmd+I)
10. Lesson 7. The buzzer
    1. 7.1. Idea: the most dangerous zone
    2. 7.2. Idea: a beep is an AND with a generator
    3. 7.3. Build
    4. 7.4. Check
    5. Lesson 7 paste (Cmd+I)
11. Summary
12. All the parts
13. Instructions in pictures