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Project #604, Mega pulser & flasher, Project #605 – Elenco Upgrade Kit SC300 to SC750 User Manual

Page 111: E” & “s” blinker

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Project #604

OBJECTIVE: To power other devices using the alarm IC.

Mega Pulser &

Flasher

In this circuit, you will power many devices using the alarm IC (U2).
Set the meter (M2) to LOW (or 10mA) and turn on the slide switch
(S1). The LED’s (D1 & D2) and bulbs (L1 & L2) flash, the meter
deflects, the whistle chip (WC) sounds, and the motor (M1) spins.

Project #605

OBJECTIVE: To use the alarm IC to flash between “E” & “S”.

“E” & “S” Blinker

This circuit alternately displays letters “E” and “S” by switching
segments “E” and “C” on and off. Segments A, D, F, and G are
connected to ground so they are always lit. Segment “C” is connected
to the base of Q2 and output of U2. The segment “E” is connected to
the collector of Q2. When the output of U2 is low, segment “C” is on
and “E” is off. When the U2’s output is high, the transistor (Q2) turns
on and segment “C” turns off. When the transistor connects the “E”
segment to ground the segment lights, displaying the letter “S”.

!

WARNING:

Moving parts. Do not touch the fan or

motor during operation. Do not lean over the motor.