Manual

This circuit produces short pulses. After you close
t
he key, the LED display shows 1 for a second and
t
hen turns off, even when you keep pressing the key.
You could create a game with this circuit. Display a
number or a letter on the LED display and then have
the players tell you what number it is. You change
numbers or letters on the display by just changing
the wiring to the display. Connect the terminals to
form the letters or numbers to terminal 71 (in the
place of the 21 and 23 terminals). Connections for
the number 3 would be 17-21-22-23-20-71.
You can try different values of capacitors to see their
effects. Don’t use a capacitor with a value higher
than 10mF or the excessive current can damage the
transistor.
Notes:
EXPERIMENT #13: VISION TEST
Wiring Sequence:
o 21-23-71
o 25-124-137
o 40-73
o 41-72
o 82-83-42-119
o 74-81-111
o 84-112-138
o 121-122
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Schematic
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