Elenco Circuit Maker Sound Plus 200 - Manual (Page 47)

Project #95
Turn Off Timer - Lamp
Project #94 Turn Off Timer
When you press the press switch (S2), the lamp (L4) turns off and the
LED lights. When the voltage from the discharging capacitor drops low
enough, Q1, Q2, and the lamp turn on and the LED turns off.
LED & Bulb Timer
Turn on the slide switch (S1). Pressing the press switch (S2) down
increases the voltage at the base of Q1. This turns the Q1, Q2, and LED
(D1) off as the capacitor (C4) charges up. As you release the press
switch, the capacitor starts discharging through resistor R5.
When the voltage from the discharging capacitor drops low enough, Q1,
Q2, and the LED turn on after a few seconds.
Replace the LED (D1) with lamp (L4) and the 100W resistor (R1) with a
3-snap wire.
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Project #96
+
+
Project #97
LED & Bulb Short Timer
You can shorten the timer delay by replacing the 100mF capacitor (C4)
with the 10mF capacitor, or by replacing the 100KW resistor (R5) with the
5.1KW resistor (R3).
CM-200_Manual_031914.qxp_CM-200_Manual_031914 4/2/14 12:04 PM Page 47