# Paperclip Circuits - Papercliptronics

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## Step 1: LED Light Circuit - Papercliptronics

LED Light Circuit on our Paperclip Breadboard.

• (1) 150 Ohm Resistor
• (1) Green LED
• (2) D Batteries

We could use a 100 Ohm Resistor instead, but would be slightly overpowering the LED by 10 mA.

## Step 2: LED Circuit - 6 LED

LED Light Circuit

• (1) 100 Ohm Resistor
• (6) White LED
• (2) D Batteries

## Step 3: Light Detector Circuit - Papercliptronics

Light Detector Circuit

• 150 Ohm Resistor- for the LED
• 120 Ohm Resistor OR 8.2 kOhm Resistor - Base of Transistor
• pnp 3906 Transistor
• LDR (Light Dependent Resistor)
• LED
• 2 D Batteries

## Step 4: Dark Detector Circuit - Papercliptronics

Dark Detector Circuit

• 100 Ohm Resistor
• 8.2 kOhm Resistor
• npn 3904 Transistor
• LDR (Light Dependent Resistor)
• LED
• 2 D Batteries

## Step 5: Water Detector Circuit - Papercliptronics

Water Detector Circuit

• 270 Ohm Resistor
• 1 kOhm Resistor
• npn 3904 Transistor
• LED
• 2 D Batteries

## Step 6: Dual LED Blinking Circuit - Papercliptronics

• (2) pnp 3906 Transistors
• (2) 180 Ohm Resistors
• (2) 100 kOhm Resistors
• (2) 470 uF Capacitors
• (2) LED's
• (2) D Batteries

## Step 7: Resistors in SERIES

What if we don't have a 150 Ohm Resistor?
That's okay.

We can use multiple smaller Resistors together instead, to achieve the correct value.

We can place two 75 Ohm Resistors in Series and they will Add Together to become 150 Ohms.

The Series Formula for Resistors is very simple:

Resistor Total = Resistor1 + Resistor2 + ... ResistorN

(ResistorN means, however many Resistors you have, you add them all together with simple addition)

## Step 8: Resistors in PARALLEL - When Only 2 Are Used

What if we don't have two smaller value Resistors either, but instead, we have two larger size Resistors?
That's okay.

We can use multiple bigger Resistors together instead, to achieve the correct value.

We can place two 300 Ohm Resistors in Parallel and they will Decrease the Total Resistance Value to become 150 Ohms.

The Parallel Formula for when ONLY 2 Resistors are used:

Resistor Total = (Resistor1 x Resistor2) / (Resistor1 + Resistor2)

## Step 9: Resistors in PARALLEL - When 3 or More Are Used

What if we only have 3 larger sized Resistors and we want the value to equal less, such as 100 Ohms?
The Parallel Formula for 3 or more Resistors:

1 / ResistorTotal = 1 / Resistor1 + 1 / Resistor 2 + 1 / Resistor3

## Step 10: Capacitor & LED Circuit

When we REMOVE power from the Circuit, the LED will Turn Off Slowly.
The reason for this is simple: The Capacitor is Discharging (LED Turns Off Slowly).

We USE a 470 micro Farad Capacitor.

If we used a bigger capacitor, the FADE OUT time would INCREASE. (longer discharge time)

If we used a smaller capacitor, the FADE OUT time would DECREASE. (shorter discharge time)

## Recommendations

• ### Large Motors Class

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