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
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
16 Step Sequencer Quantized Vari-Clock Module
A mechanism by which a normal pot could be used as a digitized pot since I need each pot`s setting to be converted to a number between 0 and 15. I use that information to determine the duration for each step. I accomplished this by designing an analog to digital convertor that could take a pot`s position and convert it to a number between 0 and...
Nixie Clock 2
The clock is constructed on two boards; one carries the HT generator and the processor logic, the other the tubes. Thisallows a slightly more compact design that the previous effort, but didn`t save as much real estate as I`d hoped. The tubes are mounted on a DIP 0. 3" grid. This isn`t ideal, but it has the advantage that the tube legs are...
nixie tube clock circuit
The nixie tube clock consists of a high voltage power supply, seven rings counters and an Atmel AVR processor. The power supply is shown in schematic Schematic 1. It takes 12 volts AC and converts it to DC which drives the Maxim 1771 switching power supply to generate 160 volts. The Maxim 1771 operates by effectively shorting the 12 volts DC to
Custom Fan Controller
This is the circuit diagram for each individual channel; Note: I replaced the 0. 1 uF timing capacitor with a 100 pF capacitor for better operation, with the 0. 1 uF capacitor in place, the fans would growl when turned down to slower speeds and the 100 pF capacitor resolved that problem. This is the circuit diagram for each individual channel;...
555 Timer LED Flasher Circuit
All of the parts in this list are generally available through Radioshack for less than $20. I highly recommend using breadboard! You`re bound to make mistakes your first time and soldering it will only make your fail worse (double fail ). I`ve compiled this tutorial into two "methods", one is the classic schematic and the other is a step by step g
This is the second part of the square root algorithm. It was developed in one month during the final stages of finishing this web site and reviewing this document for publication. While Part I dealt with an empirical discovery for a sequential algorithm to find the square root, and its subsequent mathematical proof, Part II deals with a binary sea
After an LCD workout you`ll find LED segments pretty easy to drive, so don`t worry too much about the programming! That 20M circuit shown above has code => & schematic => Tec- excuse these boring Q`s, but they`ll help us to better appreciate your quest. This esteemed forum receives many educational calls for help (including some just hours...
Most Accurate Clock
I built one of these with the RS-232 option many decades ago. It a three channel HF receiver (5, 10 & 15 MHz) that receives either the U. S. or Hawaii WWVH time and frequency broadcasts and displays the time to a tenth of a second. It also has a discipline function that tweaks a 3. 6 MHz crystal oscillator. So it could be called an HFDO, which...
Pyro Propeller Clock POV Circuit
The Pyro Propeller Clock POV schematic is actually not very difficult. There are three main parts: the power supply which uses a 7805, the LED output control which uses the PIC18F252 and 74LS373 and the `home` trigger circuit which uses an IR emitter and Phototransistor. This standard +5v power regulation circuit makes use of the LM7805 3-pin T2
Using a real time clock with a microcontroller
This is designed to be used as a programmable LED display for numerous applications. I also wanted to include some additional features so that the display can be used instantly. The display uses a sure 8 x 32 LED dot matrix. This is interfaced to a Xino (or Arduino ). The display works really nicely but I wanted a few more features for this...
AVR Color Clock
This page describes a color clock that displays the time using two RGB LEDs, one for hours and one for minutes, showing time by using the standard color coding used for components (with two additional colors as the standard color coding only has ten colors and twelve is needed). The time could have been shown more analogue by fading the colors but
68HC08 PLL Clock Generator
Nixie Tube Clock
A Burrough`s B-7971 Nixie Tube clock that I built back in 1979 when I was a senior in High School. The digits are 2 ½ inches high which allowed me to read the clock from anywhere in my bedroom without needing to wear my glasses. The clock circuit is based on a schematic that had been provided by the surplus parts vendor along
Electronic Digital Clock circuit
Digital alarm clock circuit diagram
U1 is the 3817 integrated circuit. It has the ability to drive the display directly, and it can display 12h or 24h, schedule alarm sounds, timely and automatically turn on the radio. Display is FND500 light-emitting diode, the input frequency is 50H or 60Hz. U2 is the 7800 series regulator, its rated power can meet the requirements of the radio....
Digital display electronic clock circuit
This electronic clock is composed of the LM8365 and the LDD640R displayers. The LM8365 can display the hour/minute and month/day.etc; you can set two alarm ouptuts AD1 and AD2 by pressing 12h or 24h; VDD=-21 to -6.5V, it directly drives the LED displaying; this circuit has the function of subtraction timing; when the power cuts off or there is...
The clock circuit diagram for racing
The chart shows the clock for the competition, which is assembled with 555 circuit, with the features of novel circuit, reliable performance, easy making, intuitive interesting. 555 circuit has two categories of bipolar circuit (TTL) and complementary metal oxide semiconductor-type (CMOS) integrated circuit. It is a very broad application IC with
24 Second Shot Clock
This is a circuit intended to be used in basketball shot clock.Notes:To start in 24 seconds; 24s LOAD SW and Reset SW should be push simultaneously. If not, the count will start in 99. Pulse input can be connected to 555 astable multivibrator but must be calibrated for real time clock. The PAUSE SW must have a Switch Debouncer so that the...
Schematic diagram of clock circuit composed of AT89C2051
The circuit composition determines that the LED adopts anodic Nixie tube. It can use LQ5101BS general luminous diode and the driving triode can use 2SA1015 or 2SC1815 types which is easy to gain. Of cause, the triode can also use low-power triode such as S9012, S9013, S9014, 2N5401, and 2N5555 etc. There are no special requirements for other...
MULTIPLEXED CLOCK DlSPLAY
Multiplexed display suitable for LED readouts is provided by circuit using TTL counters to count 60-Hz Iine.When count reaches o`clock, flip-flop M is set on evely cycle. Gate G3 then detects when time goes to 13 o`clock, and clears shift register.Carry flip-flop remains set, so 1 is loaded into hours digit to accomplish transition from 12:59:59...
the digital clock circuit
U1 is a 3817 integrated circuit, which is produced by Fairchild Corp. It can directly drive the display, and it can display for 12h or 24h, It can generate the clock sound and turn on the radios on time. The display is a FND500 LED, the input frequency can be 50Hz or 60hz. U2 is a 7800 voltage stabilizer whose regulated power can meet all radio...
underclock the Super GameBoy
I got myself a Super GameBoy today, but I noticed that the sound pitch is notably higher than an original GameBoy(CPU clock frequency doesn`t match between the Super GameBoy and GameBoy "Brick," 4.194304 MHz for the "Brick" and 4.295454 MHz for the Super GameBoy. I`m looking to underclock the thing, but I have no clue where the clock frequency...
Clock Controller circuit
The Clock Controller was designed to be an exemplary of using `C` language to control timer0 interrupt, 7-segment LED and keypad scanning. It provides 1-bit sink current driving output, for driving a relay, opto-triac, say. Many projects requiring 7-segment display and keypad interfacing may get the idea from the Clock circuit and software. Fi
Propeller-powered IN-12 Nixie Clock
After building so many Nixie Tube Clocks from the Internet, I finally decided to design my own. My clock uses IN-12 Nixie Tubes and an 8-core Propeller Microcontroller. The Propeller may a be a bit of overkill for the task, but it`s the microcontroller that I`m most familiar with an is easy to program. A Dallas 1302 RTC chip is used for accurate t
Microcontroller Clocking a Transmitter?
The core of any transmitter is usually an oscillator circuit, and in simple transmitters (i. e. , QRSS devices), it`s often a crystal. Frequency adjustment is accomplished by adjusting capacitance to ground on one of the crystal legs. Simple oscillators such as the Colpitts design (based on an NPN transistor) are often used. (pictured) However...
Line Ripple Clock
This circuit converts the ripple from a wall wart supply to a clean Line x 2 digitial clock. Doing it this way eliminates the need to put AC into the unit which then has to be rectified and filtered just to have access to the line frequency sine wave.
24 hour clock without the 1 hertz reference circuitry
AC DIGITAL CLOCK WITH STANDBY BATTERY
Uses MM5316 alarm-clock IC, originally designed to drive LCD or fluorescent displays, but modified here for LED display Diodes and batteries provide power if AC fails, with blanking of display to extend battery life. Accuracy is poor on batteries but batteries make resetting of time and alarm easier after AC interruption. Alarm uses 555...
USB Live Oscilloscope: Clock Generator
Produce the varying sampling clock write strobe pulses. So, I settled with this semi-optimal but working design applying an ATtiny2313 microcontroller from Atmel. For a 10MHz sampling clock, I need a 20MHz clock for the ATtiny2313and hence it needs to be powered at 5V instead of 3. 3V like all the other logic around. So, I had to add these HCT04...
Precision Clock Generator
The device presented here can generate a complementary clock signal at frequencies of 10Hz to 10MHz in steps of factor10. Thus, I chose to call it "10xHz clock generator" (with x being a number between 1 and 7). It can also be used to manually create clock impulses using a press button. The frequency is selected using two press buttons/swiches: S1
A vacuum fluorescent display (VFD) tube is a type of tube which consists of a hot cathode (filaments), anodes (phosphor) under a high vacuum condition in a glass envelope. This clock uses tube types 8843 or 8894 made by Sylvania in the early seventies. The cathode is made up of fine tungsten wires, coated by alkaline earth metal oxides, which emit
Nocrotec FIP-Clock (FIP60B30T VFD Display)
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...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial