Elenco Electronics EP-130 - Single Flash Light

-1
00
-
You’ve built many circuits usin
g
the operationa
l
amplifier, but there are lots of other ways to use this
handy IC. One of them is the single flas
h
multivibrator. With this multivibrator, you can make
the LED stay on for a preset amount of time when
the key is pressed - a single flash light
.
S
lide the switch to
p
osition B and construct the
circuit. Turn the power on by sliding the switch t
o
position A. The LED li
g
hts, but quickly turns o
ff
. Now,
press the key and observe what happens. The LE
D
li
g
hts and stays on
f
or 2 to 3 seconds and then turn
s
o
ff.
By usin
g
different values for C You can chan
g
e the
amount of time the LED is on. Change the value o
f
C
from 1
0
μ
F to 100
μ
F and see what occurs to th
e
LED. It stays on longer
.
N
otes
:
EXPERIMENT #
8
1:
S
IN
G
LE FLA
S
H LI
G
H
T
Schematic
Wirin
g
Sequence
:

31
-
63
-
94
-
131
-
138

33
-
6
7-114

85
-
68
-11
0

69
-
82
-
89
-
93

70-134

8
1-
86
-1
30
-124-11
9

90
-11
5

109
-
13
7-
129

11
3
-11
6

121-135

122
-
132