Electric Current Flow Indicator

Electric Current Flow Indicator

This Electric Current Flow Indicator gives a visual indication that there is a current flow. Possible applications for this small circuit may be: a battery charger, a voltage power source, etc.

In order to achieve our objective we place 3 rectifier diodes in series, which in turn are in series with the load / battery.

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Temperature gauge circuit using the LM324 IC

Temperature gauge circuit using the LM324 IC

Temperature gauge circuit using the LM324 IC

The temperature level is displayed using 4 LEDs: A green LED indicates that the temperature is OK.
Two yellow LEDs indicate that the temperature is higher than normal.
A red LED indicates that the temperature is very high

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Twilight switch circuit with operational amplifier and LDR

Twilight switch circuit with operational amplifier and LDR

This Twilight switch circuit activates a light, a lamp, a motor, etc., at the time of sunset and performs the reverse process at dawn.

This is an ideal circuit for activating a security light that must be on all night.

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8 LED VU meter made of IC-LM324

8 LED VU meter made of IC-LM324

8 LED VU meter made of IC-LM324.

This circuit can be used to display the variation of an audio signal in a group of 8 LEDs, behaving like a VU meter. We could use an specific integrated circuit used for VU meters, but we decided to use a readily available integrated circuit: The LM324 op amp.

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