This circuit shows you how to build a fun electronic coin flipper.
Press a button and a tiny computer chip silicon chip will instantly tell you “heads” or “tails” just like flipping a coin!
What is a Heads or Tails Decision Maker Circuit:
An electrical gadget called a “heads or tails” decision maker circuit is made to randomly select one of two alternatives, usually denoted by the letters “heads” or “tails.”
It is comparable to the idea of making a binary decision by tossing a coin.
This circuit solves basic decisions in a fun and engaging way by using logic gates and electronic components to provide a random result.
Circuit Working:
Parts List:
| Category | Component | Value/Type | Quantity |
|---|---|---|---|
| Resistors | 100k | 1/4 watt | 1 |
| 470Ω | 1/4 watt | 1 | |
| 150k | 1/4 watt | 2 | |
| Capacitors | Ceramic | ||
| 4.7nF | 1 | ||
| 100pF | 2 | ||
| Electrolytic | 1µF 25V | 1 | |
| Semiconductors | Transistors | BC557 | 2 |
| Integrated Circuit | IC4093 (N1 to N4) | 1 | |
| LEDs | Red / Green | 2 | |
| Switches | ON / OFF Switch | 1 | |
| Push to OFF Switch | 1 | ||
| Other | Battery | 9V | 1 |
The combination of gate N1, R1 and C1 operates as a square wave generator controlling the flip flop involving N3 and N4 through N2.
The flip flops outputs activate LEDs D1 and D2 alternately via transistors T1 and T2.
Pressing the button causes the LEDs to rapidly blink.
When the button is released one specific LED remains illuminated while the other goes completely dark.
These LEDs can be designated as ‘heads or tails’ yielding a truly random decision.
Although initially considering a third LED for not sure it, was discarded recognizing that professionals today possess the capability to independently make numerous decisions.
On a serious note the circuit is remarkably sensitive ensuring that the ‘heads and tails’ output is genuinely accurate and 100% random.
While there may be numerous hobby electronic circuits available, these are the ones currently presented.
Formulas:
Simple formula for NAND gate oscillators that yields an approximate frequency (f) with the following assumptions:
Time constants for charging and draining that are equal:
This indicates that for both the charging and discharging routes, the resistor and capacitor values are the same (R1 = R2 and C1 = C2).
Optimal NAND gate performance: This disregards the gates internal propagation delay.
Based on these presumptions, the formula is as follows:
f = 1.44 / (R * C)
where,
- f: Frequency of the oscillation in hertz (Hz).
- R: Resistance value in ohms (Ω).
- C: Capacitance value in farads (F).
Note:
The real frequency may differ significantly from this estimate owing to non ideal component behavior, gate propagation delay, and power supply fluctuations.
A more precise estimation of the oscillation frequency can be obtained using oscilloscope readings or circuit modeling software.
How to Build:
Building an electronic heads or tails device requires some basic electronic components and circuit assembly skills.
Prepare the Silicon Chips:
- Set up the digital logic gates using silicon chips on the breadboard.
- Connect inputs and outputs as needed.
Square Wave Generator:
- Create the square wave generator using Gate N1, R1 and C1.
- This will control the flip flop.
Flip Flop Setup:
- Connect the flip flop using NAND gates N3 and N4.
- Ensure that the output alternates between two states.
LED Control:
- Use transistors T1 and T2 to control the LEDs D1 and D2.
- Connect them so that they alternate between ON and OFF states.
Push Button Integration:
- Connect the push button to the circuit.
- Ensure that pressing the button initiates the decision making process.
Power Supply:
- Connect the circuit to a suitable power supply.
- This can be batteries or another appropriate power source.
- Test the circuit by pressing the button and observing the LED alternation.
- Ensure that the decision output appears random.
Notes:
Remember to use the appropriate resistor values, capacitor values and other component specifications based on the requirements of the chips and components you are using.
Double check your connections and, if possible simulate the circuit before building it physically.
Conclusion:
This type of electronic decision maker can be used for various purposes such as settling disputes, making simple choices, or adding an element of randomness to games or activities.
It is a creative application of electronic components to mimic the randomness associated with flipping a coin.
If any have been overlooked your valuable comments are welcome for updates.