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Project #455
OBJECTIVE: Use the whistle chip and relay to make sound.
Turn on the switch (S1) and the relay (S3) opens and closes
continuously. This creates an AC voltage across the whistle chip
(WC), causing it to vibrate and sound.
Relay & Buzzer
Project #456 Project #457
OBJECTIVE: Use the speaker and relay to make sound.
Relay and Speaker
OBJECTIVE: Light the LED and Bulb using the relay.
Relay, LED, & Bulb
Use the circuit from project 455. Replace the whistle chip (WC) with the
speaker (SP). Turn on the switch (S1) and now you generate a louder
sound using the speaker.
Use the circuit from project 455. Replace the whistle chip (WC) with the
red LED (D1). Turn on the switch (S1) and the LED lights. Replace the
LED with the 6V bulb (L2), turn on the switch (S1) and the bulb lights.