• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar

Homemade Circuit Projects

Get free circuit help 24/7

  • +1000 Circuits
  • Hobby Circuits
  • Basic Circuits
  • Learn Arduino
  • Logic IC Pinouts
  • Disclaimer
You are here: Home / Mini Projects / Simple Kitchen Timer Circuit – Egg Timer

Simple Kitchen Timer Circuit – Egg Timer

Last Updated on February 23, 2020 by Swagatam 4 Comments

A kitchen timer is a useful gadget which produces an alarm sound after a predetermined delay, as set by the user for specific time based food recipes that must be cooked only for a certain amount of time for best results.

Written By: Suneeta Dixit

One example is boiled eggs which may be either hard boiled, medium boiled or soft boiled depending upon how long it is allowed to boil.

For such applications, a kitchen timer can be quite handy, and will provide the user with a warning alarm after the stipulated time is elapsed, so that the user can shut off the flame and avoid the food from getting overcooked or for getting the right desired texture and taste on the food.

How it Works

The kitchen timer circuit with alarm or an egg timer explained in this article could be built very cheaply, and it features an adjustable delay time setting between 1 minute and 17 minutes.

Other time ranges may be possible through little alterations. Initially while the circuit is not powered, capacitor C1 and C2 are uncharged.

As soon as the unit is turned on with switch S (position 1), input A of the flipflop N1 /N2 stays temporarily at '0V', to ensure that output Q of N2 turns into 0 and multivibrator N3/N4 is disabled. Next, capacitor C1 begins charging through potentiometer P1 and P2.

Once the voltage at point B becomes lower than the flipflop's switching threshold, the flipflop toggles and this initiates the multivibrator action.

This initializes the square wave frequency from the multivibrator which is amplified by the transistors T1 and T2 and the resulting tone output is reproduced through loudspeaker L.

When the kitchen timer is switched OFF (S moved to position 2), capacitor C1 begins discharging swiftly via resistor R1 to ensure that, once the timer switched on again for the next cycle, no left over charge remains in the capacitor which may otherwise cause reducing the timing length.

How to Calibrate

1. Adjust P1 at the center of its journey and adjust P2 to its minimum setting range. After that readjust P1 to allow a period of 1 minute.

2. Next, set up P2 to its maximum possible range and determine the time interval generated from the circuit.

3. Lastly calibrate the scale of P2 with a linearly increasing scale from a range of 1 minute minimum, and the maximum which was determined practically earlier.

PCB Design and Component overlay

SHARING IS CARING!



Previous: Car Warning Tone Generator for Ignition, Headlight, Turn Lights
Next: Gadgets to Protect Women from Assaults and Harassment

About Swagatam

I am an electronic engineer (dipIETE ), hobbyist, inventor, schematic/PCB designer, manufacturer. I am also the founder of the website: https://www.homemade-circuits.com/, where I love sharing my innovative circuit ideas and tutorials.
If you have any circuit related query, you may interact through comments, I'll be most happy to help!

You'll also like:

  • 1.  PIR Solar Home Lighting Circuit
  • 2.  2 Simple Induction Heater Circuits – Hot Plate Cookers
  • 3.  Simple Peltier Refrigerator Circuit
  • 4.  Input Trigger Synchronized Monostable Timer Using IC 555
  • 5.  Simple Faraday Flashlight – Circuit Diagram and Working
  • 6.  Simple 1.5 V Inductance Meter Circuit

Please Subscribe (Only if you are Genuinely Interested in our Newsletters)


 

Reader Interactions

Comments

    Your Comments are too Valuable! But please see that they are related to the above article, and are not off-topic! Cancel reply

    Your email address will not be published. Required fields are marked *

  1. Search Related Posts for Commenting

  2. Marvin Manuel says

    Swagatam… I request you ckto to reverse the 3 / 4hp single-phase motor turn… start right for 5 mints, stop 1/2 sec and start opposite turn for 5 mins…
    and so on for a while … washing machine type, maybe digital analog … thanks

    Reply
    • Swagatam says

      Thank you Marvin, I’ll try to update the washing machine motor design soon in the washing machine article

      Reply
  3. Marvin Manuel says

    Man, the subject is excellent and very necessary…. At the output you could put a relay … the combination of the flip flop and the multivibrator is very good and the times can be lengthened or shortened … the magic is the digital-analog hybrid, I am fond of electronics …. I’m looking for a timed reversal turn for 10min, stop 1sec, reverse turn 10 min, stop 1sec and continue… like the washing machine… maybe there is something in the rest of the timers…. I congratulate you very well on your website … greetings

    Reply
    • Swagatam says

      Thanks friend for liking and appreciating my work! I am glad you found the article useful! Please keep up the good work!

      Reply



Primary Sidebar

Electronic Projects Categories

  • 3-Phase Power (15)
  • 324 IC Circuits (19)
  • 4017 IC Circuits (51)
  • 4060 IC Circuits (25)
  • 555 IC Circuits (93)
  • 741 IC Circuits (18)
  • Amplifiers (49)
  • Arduino Engineering Projects (82)
  • Audio Projects (84)
  • Battery Chargers (76)
  • Car and Motorcycle (88)
  • Datasheets (45)
  • Decorative Lighting (Diwali, Christmas) (32)
  • DIY LED Projects (82)
  • Electronic Components (97)
  • Electronic Devices and Circuit Theory (35)
  • Electronics Tutorial (99)
  • Fish Aquarium (5)
  • Free Energy (34)
  • Games (2)
  • GSM Projects (9)
  • Health Related (17)
  • Heater Controllers (24)
  • Home Electrical Circuits (98)
  • Incubator Related (6)
  • Industrial Electronics (27)
  • Infrared (IR) (39)
  • Inverter Circuits (94)
  • Laser Projects (10)
  • LM317/LM338 (21)
  • LM3915 IC (24)
  • Meters and Testers (55)
  • Mini Projects (153)
  • Motor Controller (65)
  • MPPT (7)
  • Oscillator Circuits (15)
  • PIR (Passive Infrared) (8)
  • Power Electronics (33)
  • Power Supply Circuits (65)
  • Radio Circuits (9)
  • Remote Control (46)
  • Security and Alarm (56)
  • Sensors and Detectors (116)
  • SG3525 IC (5)
  • Simple Circuits (72)
  • SMPS (29)
  • Solar Controllers (60)
  • Timer and Delay Relay (51)
  • TL494 IC (5)
  • Transformerless Power Supply (8)
  • Transmitter Circuits (39)
  • Ultrasonic Projects (12)
  • Water Level Controller (46)

Follow Homemade Circuits

Facebook
Twitter
YouTube
Instagram
My Facebook-Page
Quora

Feeds

Post RSS
Comment RSS

Circuit Calculators

  • AWG to Millimeter Converter
  • Battery Back up Time Calculator
  • Capacitance Reactance Calculator
  • IC 555 Astable Calculator
  • IC 555 Monostable Calculator
  • Inductance Calculator
  • LC Resonance Calculator
  • LM317, LM338, LM396 Calculator
  • Ohm’s Law Calculator
  • Phase Angle Phase Shift Calculator
  • Power Factor (PF) Calculator
  • Reactance Calculator
  • Small Signal Transistor(BJT) and Diode Quick Datasheet
  • Transistor Astable Calculator
  • Transistor base Resistor Calculator
  • Voltage Divider Calculator
  • Wire Current Calculator
  • Zener Diode Calculator
  • Privacy Policy
  • About Us
  • Contact
  • Disclaimer
  • Videos – Circuit Test Results

© 2021 · Swagatam Innovations