Zener diode rated 3.3V maintains the required 3.3V for UM66 IC. The output from Vo of UM66 is amplified by BC547 transistor.
Click on the video to see the output

Learn how to use UM66 or BT66

Zener diode rated 3.3V maintains the required 3.3V for UM66 IC. The output from Vo of UM66 is amplified by BC547 transistor.
Click on the video to see the output

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