Manual

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multivibrator – are you able guess what astable
m
eans? Generate a guess, and complete this
project to see if you were right.
To turn the circuit on, connect terminals 13 and 14.
LED 1 begins to flash. Astable means the
multivibrator’s output keeps switching back and
forth between 0 and 1. So far most of the
multivibrators that you have built do the same
things.
You shouldn’t trouble figuring out how this particular
circuit works. The 100mF capacitor is the key. In
place of the 100mF capacitor, try using other
electrolytic capacitors and see what result they
have on LED 1 (Be sure to apply the correct
polarity.)
By now can see why NAND gate ICs are so useful.
Quad two-input NAND ICs, like the one in this set,
are among the most widely used electronic
components in the world, because there are so
many different types of circuits that they can be
used in.
Notes:
EXPERIMENT #50: ASTABLE MULTIVIBRATOR USING TTL
Schematic
Wiring Sequence:
o 13-49-31
o 14-119
o 33-58
o 50-51-77-115
o 54-53-52-75-78
o 55-56-57-76-116
o 59-60-62-121
o 13-14 (POWER)
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