Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
Analog to Digital
Data Bus Circuits
Voltage to Pulse
Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
Voltage to Current
voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
Use a PC`s parallel port to program a clock source
This Design Idea shows how you can use Linear Technology`s LTC6903 programmable oscillator as a clock source for direct-digital synthesis, data conversion, switched-capacitor filtering, clock, and voltage-controlled oscillator circuits.
Use a system`s real-time clock to "hide" a code sequence
Although the concept of a totally accessible system represents an ideal situation for users, designers now must limit access toand conceal code sequences forsoftware routines for calibration, diagnostics, memory erasure, system reset, and more. In a system that includes a computer-compatible interface, such as an RS-232, a GPIB, or an...
VCXO makes inexpensive dual-clock reference
This Design Idea describes an inexpensive circuit to generate two extremely high-quality, crystal-clock-reference-signals, one of which is a PWM-controlled VCXO (voltage-controlled crystal oscillator) clock signal (Figure 1).
Video Clock Superimposer
As a followup to my VCR Pong project, here is a gadget that is actually useful in the Real World! It superimposes the time of day, in "HH MM SS" format, in the bottom right-hand corner of an existing video signal. My friend Scott uses it with his home security system.
AVR Microcontroller Digital Clock with ATtiny2313
Usually we see Digital clock on LCD or 7 segmen. But, this AVR Digital Clock which is designed by Ficara Emilio displayed on Oscilloscope. The project use ATtiny 2313 as the main controller. What an interesting microcontroller project. Source code and schematic available for download..
Digital Clock circuit with CMOS 4047
This circuit provides a digital square wave that can be viewed directly or used to drive other circuits. It used the CMOS 4047 Low-Power Monostable/Astable Multivibrator. As used in Tom Duncan's Adventures with Digital Electronic's Book, to drive CMOS Decade of 4-bit binary counters.
Clock circuit using SX 28 internal oscillator
The SX 28 internal oscillator Is not that fast so an external oscillator can be hooked up to the processor as shown in the diagram to increase the operation cycles per second.
MSF Radio Time Clock
The National Physics Laboratory broadcasts a time signal, previously known as the Rugby clock but now called "Time from NPL." Its most commonly known as the MSF signal due to it originally being identified in Morse code those letters. It is broadcast from Anthorn on 60kHz. Many commercial clocks use it to automatically set themselves. I decided...
Morse Code Alarm Clock
(Almost) Trivial application of an AT90S2313 or ATtiny2313 in an alarm clock to change the alarm from "BEEP BEEP BEEP BEEP BEEP BEEP BEEP BEEP..." to "WAKE UP" in Morse code. This was designed in response to a request and is in daily use. An inexpensive alarm clock was modified by installing a small circuit board inside the clock body and...
Clock using a Hard Drive
Have an old hard drive that no longer works? As long as it still spins up chances are you could build a clock out of your old hard drive! You will need some electronic knowledge, some common electronic components and a bit of patience. The clock that is produced isn’t exactly practical since most hard drives (especially older ones) are too loud...
Digital Clock with 6 nixies
The clock will have 6 digits and time setting will be done by means of a few buttons. I will try to use the most common types from widely used microcontroller families of miscellaneous producers. I will write the program in C language. Nixies need high voltage for operation. I wanted to avoid dangerous mains line voltage. The supply voltage for...
Greenhouse irrigation controller ( PIC16F84 )
This is a simple one-valve irrigation controller made for our greenhouse. The code contains a software real-time clock (RTC) and a multiplexed 8-digit LED display and keyboard you can use in other projects. The operating software is simple, it contains a real-time clock and a day counter. The valve is turned on in regular intervals in the same...
Led Clock using PIC16F84
Using only 2 capacitors, 3 resistors, 4 seven-segment Display, 1 xtal, 2 switches n.o. and 1 Microcontroller PIC, you can build this Digital Led Clock. you can use common anode or common cathode display, just select the display type. Here is the pinout information: Pin 3 defines the display type. If you will use common cathode display, connect...
LCD digital Clock using PIC16F628
The reason why I'm using a LCD display is because it allow me to display many characters and it doesn't need to be "refreshed" as 7-segment Led displays. Also, the interface requieres less I/O pins. For this project I used a 16x1 LCD Display with 4-bits interface.
The digital clock of circuit, has as base one IC, the MM5314N, in which are contained all the circuits that need. The IC1 collaborates with six Display of common anode, that are not critically as materials. You can select what dimension, you want it is enough you adapt pins their in the circuit. The display are drive by a system of polyplexis...
Gear clock using PIC 16f628A
The heart of the clock is a PIC 16f628A microcontroller (PDF). This microcontroller has an internal oscillator however an external 20MHz crystal oscillator is being used since it will have to accurately keep track of time for weeks and months. The microcontroller is interfaced to two buttons and one motor. The interface is very simple, it...
Clock using analogue multimeters ( PIC16F628A )
The Multimeter Clock consists of three multimeters, the first meter displays hours, the second displays minutes and the last displays seconds. A 16F628A PIC microcontroller keeps track of time and outputs a calculated current to each meter to display the current time. The user enters the time by pressing three time adjust buttons. The first...
19 LED Clock circuit
The clock circuit above uses seven ICs and 19 LEDs to indicate binary coded decimal time. The LEDs can be arranged (as shown in example above) so that each horizontal group of 3 or 4 LEDs represents a decimal digit between 0 and 9 and each individual LED represents a single bit or (binary digit) of the value. Binary digits have only two values...
Digital Clock with Solar Regulator
The basic clock circuit (top schematic below) is similar to the binary clock (on another page) and uses 7 ICs to produce the 20 digital bits for 12 hour time, plus AM and PM. A standard watch crystal oscillator (32,768) is used as the time base and is divided down to 1/2 half second by the 4020 binary counter. One half of a 4013 data latch is...
Quartz Crystal Windup Wall Clock
Last year, I found a 31 day pendulum wall clock (dissambled) in a box of parts at a swap meet and decided to try and put it together and regulate it with a quartz crystal oscillator. The escapement part that rocks back and forth and drives the pendulum was missing and had to be made from a couple razor blade pieces and heavy copper wire. The...
Digital Clock Timer schematic
This clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit time and control an external load. The clock includes a calendar with leap year and optional daylight savings adjustments. The timer output can be set from 1 to 59 minutes and manually switched on and off. The clock also has a correction feature that allows an...
Radio alarm clock
The program makes use of the built-in AD converter of the PIC16F874 for sensing the touch buttons. The PIC has 8 AD ports, seven are used for the 7 touch-buttons, 1 is used for the light measurement. In order to receive DCF signals, you have to add a DCF module (e. g. Conrad nr. 641138 - 89) which will provide a digital TTL level DCF signal which i
Car clock temp voltmeter
This device was designed to replace the original digital clock in a Fiat Ducato 1992-1994, mounted just above the inside rearview mirror. The original clock is not very accurate, only displays time and is sensitive to interference (e. g. from Xenon headlights). The replacement device described here does not have these disadvantages, and on top of t
The 7490 counter is a negative edge triggered decade counter that counts from 0 to 9. Pins CLKB & QA must be connected for this counter in order that it would operate in the decade mode. The inputs R0(1, 2) & R9(1, 2) are asynchronous reset pins, one of each must be low for counting, if both the R9(1, 2) inputs were high, then the counter will...
PIC16F628 Digital Clock Timer circuit and explanation
This clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit time and control an external load. It can be programmed to time from 1 to 59 minutes. The clock includes a calendar with leap year and optional daylight savings adjustments. The timer output can be set from 1 to 59 minutes and manually switched on and off. The clock also
Digital Clock Using Microcontroller 89C52/89S52
Are you a beginner in micro controller projects and are you stuck where to start from if yes, then this is one of the simplest mini projects that you can start from. This mini project will give you a clear understanding of programming your micro controller. we sometimes look at our watch and wonder " how does this thing work". Well, in this digita
0 to 24 hour clock
Analog Clock And Temperature sensor On An Oscilloscope using Arduino
Scopeclock is an easy to use hardware to make your X-Y capable analog oscilloscope more useful. Using this simple to use hardware you can convert your analog oscilloscop
Arduino 7 segment Displays Digital Clock With Charlieplexing LEDs
This is my second instructable. I just had a mood of making a digital watch. But wanted to make it a learning process. I already had a sanguino i could have easily used that Atmega644 chip. it would have been more than enough. But i wanted to try burning a Arduino bootloader and see if i could make it work. Well i did. I used a Atmega168 for this
Colorful Countdown Clock for tight timeline management using Arduino
Well, I have few good uses for it, one of them is ensure in meetings people are respectful of time and are not taking all the time for their own topics. Good for ship-room or SCRUM meetings. Following is a list of parts and for the special ones a link for where you can buy them. Consider searching eBay or other stores for getting best prices. Y
DIY Binary Clock with Arduino
Yesterday I was going to start watching a movie, when me and my friendpedrodecided to give up on the movie and build a binary clock. After sometime thinking on how to program it, we made it. It works beautifully, so I decided to show here how I`ve done. It may not be the easiest way to make it work, but that`s what we`ve done. To assemble the circ
Make an Atom Synchronised Clock from a 1950s Slave Dial using Arduino
When I purchased the salve dial, it came with no instructions, packaging or other details. The only markings (other than five decades of grime) were those on the face (SMITH SECTRIC, ACELEC SYDNEY), and some markings on bracket holding the mechanism together (E. C. S. 205/19 MADE IN ENGLAND). There were markings on the coil, but they were too faint
Frequency Meter Circuits
VU Meter Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity