|
|
|
The circuit below can be used to test a person’s reaction time to a precision of ±0·01 seconds.
The time is indicated by a series of seven leds showing the output of a binary counter (4060). The two D type flip-flops are in a 4013.
The led shown on the circuit diagram is the "stimulus". Switch S1 starts the timer and illuminates the
stimulus led. Switch S2 stops the timer.
|
|
 |
|
To calibrate the timer |
|
1. |
Remove the 4013 from its holder; this allows the oscillator in the 4060 to run continuously. |
|
2. |
Connect the battery and then connect an oscilloscope across the first led
(that is, the led which is connected to pin 7 of the 4060). |
|
3. |
Adjust the variable resistor to produce an oscillation of time period 10ms. |
|
|
Vero diagram
|
|
 |
|
 |
Top of the Page
|
|
The Open Door Web Site