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
Fast Optical Recording Circuit
This document presents technical details, hardware and software of a complete imaging system which uses a fast CCD sensor and a 41 Msample/s A/D converter to acquire full-frame 12 bit/pixel digitised images with a time resolution of 1.25 ms/image. The noise characteristics and the photon-capture capabilities of the system were analysed in...
You must be able to recognise components such as capacitors, diodes, zeners, transistors and resistors to build 5x7 Display project. This information is covered in our BASIC ELECTRONICS course and a complete set of circuit symbols can be found HERE.
LC meter 16x1 LCD Display
This is one of the most accurate and simplest LC inductance / capacitance Meters that one can find, yet one that you can easily build yourself. This LC Meter allows to measure incredibly small inductances starting from 10nH to 1000nH, 1uH to 1000uH, 1mH to 100mH and capacitance from 0.1pF up to 900nF. LC Meter`s circuit uses an auto ranging...
1 GHz Frequency Counter
This very simple counter can be used to measure the frequency of various wireless devices. Applies in reviving the transmitter and its operation as a control monitor frequency. It can be used as a scale to the receiver. Due to the simplicity of the counter should not miss any of the equipment bastlí?e that similar facilities are still owned....
Digital LCD thermometer ( PIC16F871 )
The circuit drives the LCD pins with 50% square waves. Each segment on this LCD is connected to the COM backplane and a separate pin. When a pin is driven in phase with the COM pin, the corresponding LCD segment gets zero voltage, and is off. When a pin is driven in reverse of the COM pin, the corresponding segment gets an alternating voltage,...
68HC11 as a Digital Timer
The timer is proposed an effective model for controlling an external load 8A/380V. Equipped with a 68HC11 mu.P associated with an 8 MHz crystal, it can get very precise programmable durations. Two lines are planned: from 0 to 99 seconds and from 0 to 99 minutes. Both displays allow programming in conjunction with a 4-button keypad. They also...
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...
A/D converter 16Bit with LCD and PIC18F2550
The analog to digital converter (ADC) is a commonly required in most of the projects. Analog voltage measurement can be done using the ADC hardware built in together in a PIC. The picture below show a simple setup for measuring the voltage through the adjustment of the potentiometer. PIC used in this example come with a 10 bit ADC. In the...
PWM controller with PIC18f2455
The use of pulse width modulation (PWM) is common for the use of controlling power to a particular electrical device. Motor speed control, LED contrast control, power supplies are some of the example usage of PWM. 18 series PIC always come with a CCP module which is capable of generating PWM. The picture below shows an example of using the...
Roulette with LED Display
This circuit is a small digital ?roulette''. It is constituted by oscillator IC1, the counter IC2, the transistors Q1-7 that drive the display common cathode DSP1. The supply basically becomes from a battery 9V, but can become also from one power supply. The regulation of frequency should become in the 10HZ or little bigger, with to...
Frequency counter up to 1MHZ
The MK50398 is one modern decimal counter up/down of six tens, with control of screen LED of seven segments and flip-flop of storage. Counter it can measure additive and abstractively. The IC MK50398 is ideal for manufacture frequency counter as the particular circuit. The frequency of measurement is from 0 HZ until roughly 1MHZ.
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...
Digital Voltmeter with ICL7129ACPL A/D converter
This 4 1/2-digit DVM circuit is built around a Maxim ICL7129ACPL A/D converter and LCD driver. An ICL8069 CCZR 1.2-V band-gap reference diode is used for a voltage reference. S2a-b-c select one of four ranges up to 200 V (maximum). The meter also has a piezoelectric buzzer for continuity testing. S3 selects either DVM or continuity. Crystal 1...
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...
Repair Notes of Ten-Tec Corsair 560 Digital Readout
The Digital Readout of the Corsair 560 is just above the tuning knob. On this particular radio these six digits bounced around, often doubling the frequency indication. The reading was so unstable, it was difficult to know what frequency the radio was tuned to. Below is a picture of the display after the repair. It is fairly solid down to the gree
An Overly Sensitive One-Shot
This circuit is from the data sheet for Linear Technology`s LT1720 (a 4. 5ns comparator). It`s the circuit entitled "Pulse Stretcher" at the very end. Essentially, it`s a one-shot with sensitivity down to 14mV for 5ns to 10ns inputs (i. e. , it doesn`t require a full swing from logical low to high as do most one-shots), and TTL logic level...
The CDMS II Veto Readout Electronics
A Prototype Sample and Hold Circuit -The original idea for the veto front end amps was to continually sample the input pulse height and hold the pulse height for any pulses passing a low voltage threshold (~10mV). This mixed analog and digital circuit was actually made to work. Unfortunately, the highly variable risetimes of the input pulses cause
9 second digital readout countdown timer
This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with the output held high..
Lambda Probe Readout For Carburettor Tuning
A lambda probe (or oxygen sensor) can be found on the exhaust system of most cars running on unleaded fuel. Having reached its normal operating temperatur..
9 Second Digital Readout Countdown Timer
This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with the output held high. When the switch is opened, the timer produces an approximate 1 second clock signal, decrementing the counter until the 0 count is reached.
Two chip Frequency Meter with binary readout circuit
Now, when the construction is nearly done, here is a circuit diagram. When I finally settled on how it was going to be done, and set it down on paper,..
3-D Depth Finding Imager with Digital Readout
The objective of the project is the design of an imager chip for laser-scanned 3-D depth/range finding. The project is divided into two modules: Pixel Array/Centroid Detection and Analog-to-Digital Conversion (ADC). The pixel array/centroid detector tracks the centroid of the laser beam as its scans the object while the ADC converts the analog out
5A Lab Power Supply With Digital Readout
A used 250VA power transformer that was removed from equipment a couple of weeks ago. The transformer has a dual 10V AC output and a few auxiliary voltage outputs. The 10V winding is rated at 10A, I thought it would be perfect for a high current power supply project. For this particular build, I used the reference design for LM338 5A adjustable...
9 Second Digital Readout Countdown Timer
This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with the output held high. When the switch is opened, the timer produces an approximate 1 second clock signal, decrementing the counter until the 0 count is...
LIGHT METER WITH LED READOUT
Light onphototransistorQ1 (Radio Shack 276-130) produces voltage change across R2 for amplification by opamp whose output drives array fiveLEDs forming bar graph voltage indicator. Adjust R3 initially for highest sensitivity by tuming off room lights and rotating until LED 1 just stops glowing. Now, as light is gradually increased on sensor, LEDs
ANALOG TACHOMETER READOUT
The analog display consists of a frequency/voltage converter (IC12) and bar-graph segment drivers IC10 and IC11. R34 is the calibration adjustment and is set so that an engine rpm of 5000 to 7000 rpm lights the first LED (redline value).
RING COUNTER WITH VISUAL READOUT
Uses only six components per stage. Combining of counter and indicator functions gives low battery drain. After reset button is re leased, 0. 22-mid capacitor insures that first stage turns on. Current is drown by stage only when lamp is on. Any number of stages may be included in ring. -"Transistor Manual, " Seventh Edition, General Electric...
BAR GRAPH READOUT VOLTMETER
Sections of RS339 quad comparator each drive LED to give indications of four different input voltage levels, While LED 1 is connected to ground for use as zero indicator Resistors shown are for Radio Shack 276-041 red LEDs ›change R6-R9 to 270 ohms and R1 to 470 ohms for green LEDs Pot R1 is used to calibrate voltage divider R2-R5 With R1 set all
Digital to Analog Circuits
Analog to Digital Circuits
Data Logging Circuits
Data Bus 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