Elenco Electronics EP-130 - Initials on LED Display

-
102
-
The di
g
ital LED can’t display all 26 letters o
f
th
e
alphabet, but it’s possible to exhibit many of them
.
L
et
’
s ma
k
e an
LED
di
sp
l
ay t
h
at
i
ntersperse s
h
ows
the initials E and P of our ELE
C
TR
O
NI
C
PLAY
G
R
O
UND. You can show other initials too.
Slide the switch to position B and construct th
e
circuit. Once you have completed the wiring, slide th
e
switch to position A to turn on the power, and you’ll
observe the letters E and P li
g
htin
g
alternately on th
e
LED display
.
I
C
1 works as an astable multivibrator and exhibit
s
the letter E. IC 2 is used as an inverter, with an out
p
u
t
that is opposite to that of I
C
1; it displays the letter P
.
Now that you’ve success
f
ully displayed the letters
E
and P, why not try showin
g
other letters? It should be
eas
y
i
f
y
ou take a close look at the schematic.
N
otes:
EXPERIMENT #83: INITIALS ON LED DISPLA
Y
S
chematic
W
iring
S
equence:

22-17-1
8
-1
9
-
63
-1
3
1-
8
1

20-65-67-90-94

21-
6
4

83
-114-7
0
-2
5
-121

66
-
69
-
82
-
84
-
89

93
-
68
-11
3

1
1
9
-124

122
-
132