Duration: 23:35

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8

One thing I didn't say in the video is that the output of most 74HCxx logic gates can only source or sink small amounts of current. In the case of the SN74HC7001 used in this circuit, the guaranteed amount is 4mA. Fortunately, bipolar transistors can be used to control large currents with much smaller ones.

Futurelec NE558 - https://www.futurlec.com/Linear/NE558Npr.shtml

AdaFruit LED light & beeper tower - https://www.adafruit.com/product/2994

Falstad Circuit Sim import code -

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