Elenco 130-in-1 Electronics Playground - Manual (Page 102)

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The digital LED can’t display all 26 letters of the
alphabet, but it’s possible to exhibit many of them.
Let’s make an LED display that intersperse shows
the initials E and P of our ELECTRONIC
PLAYGROUND. You can show other initials too.
Slide the switch to position B and construct the
circuit. Once you have completed the wiring, slide the
switch to position A to turn on the power, and you’ll
observe the letters E and P lighting alternately on the
LED display.
IC 1 works as an astable multivibrator and exhibits
the letter E. IC 2 is used as an inverter, with an output
that is opposite to that of IC 1; it displays the letter P.
Now that you’ve successfully displayed the letters E
and P, why not try showing other letters? It should be
easy if you take a close look at the schematic.
Notes:
EXPERIMENT #83: INITIALS ON LED DISPLAY
Schematic
Wiring Sequence:
22-17-18-19-63-131-81
20-65-67-90-94
21-64
83-114-70-25-121
66-69-82-84-89
93-68-113
119-124
122-132