Manual

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Project #640
OBJECTIVE: To construct an LED strobe light.
Strobe Light
This is an example of how a large strobe light works. Turn the slide
switch (S1) on and the LED (D2) flashes at a certain frequency. Adjust
the frequency by adjusting the adjustable resistor (RV). Now add
sound by replacing the 100Ω resistor (R1) with the speaker (SP). Each
time the LED lights, the speaker sounds.
Project #641
OBJECTIVE: To demonstrate the operations of the AND gate.
AND Gate
In digital electronics, there are two states, 0 & 1. The AND gate performs
a logical “and” operation on two inputs, A & B. If A AND B are both 1, then
Q should be 1. The logic table below shows the state of “Q” with different
inputs and the symbol for it in circuit diagrams.
In the circuit, the S1 & S2 switches represent inputs A & B, and the D7
display represents output Q.
A B Q D7
0 0 0 “L”
1 0 0 “L”
0 1 0 “L”
1 1 1 “H”
A
B
Q
AND Gate