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
FinFET domino logic with independent gate keepers
Charge-sharing symmetric adiabatic logic in countermeasure against power analysis at cell level
DARLINGTON LOGIC PROBE
Two-transistor Darlington connection provides very high input impedance that does not load logic circuit being monitored, while driving LED that glows when logic 1 is present at input.-F. M. Mims, Computer Circuits for Experimenters, Radio Shack, Fort Worth, TX, 1974, p 35-43..
Five uses tri-state audio logic pen (CD4066 555) circuit diagram
Five uses tri-state audio logic pen (CD4066, 555) circuit diagram is shown as the chart. The circuit is mainly composed of the multivibrator, the four-way switch CD4066 (IC1) and the gate circuit composed of some RC components. Multivibrator is composed of the 555 (IC2) and R7, R8, R9, C1, and its frequency is controlled by IC1-3 on-off state.
TICK TACK TOE LOGIC
Neon lamps serve as diode gates and indicate positions and moves on game board. Thyratron-relay com bination serves as memory, while relays referee sequence to prevent two successive moves by either player. -C. E. Hendrix and R. B. Purcell, Neon Lamp Logic Gates Play Tick-Tack-Toe, Electronics, 31:25, p 68-69.
The logic circuit diagram composed of photocoupler
Figure 1 is AND gate logic circuit. Its logic expression is P=A, Figure B has 2 photodiodes in series. When input logic level A=1, B=1, output P=1. In a similar way, itcan form Or gate, NAND gate, NOR gate and some other logic circuits. As shown in figure 2, it is a typical AC coupling amplifier circuit, which is suitable for selecting lightin..
Logic Power Control circuit diagram for 78xx Regulator
Logic power control of analog regulator can be useful in application where a digital circuit/controller need to control power source, such as in EEPROM programmer or other power controls. This is a circuit provide ON-OFF control for 78xx regulator using digital (TTL or CMOS) signal level. This circuit uses transistors in series with the 78XX...
Circuit Diagram of Audio Logic Level Probe Composed of 555
The above picture is audio logic level probe circuit, which is composed of voltage comparator, multivibrator, and piezoelectric ceramics HTD etc. The latter two constitute audio circuit and the audio frequency is used to assess the TTL or COMOS instrument s electrical level. When the probe reaches high level, IC-1 sends out signal to make D2...
The figure shows the schematic for a versatile logic probe. The zener diode clamps the input signal just above the TTL inverter`s 2.2-V trigger voltage. Zener diode D1 can be left out if the probe is going to be used only on TTL circuits. The logic probe is based mainly on inverters IC1-a and IC1-b, which are sections of a 7404 integrated...
4-input mini Logic Analyzer
This mini Logic analyzer is a tool for you to watch on LCD the logic transitions 0 or 1 of a digital data signal. A digital data signal can be found on the output pin of TSOP-1730 Infrared Receiver, on the Transmit and reveive pins of MAX-232 chip (RS-232), on Clock and Data pins of I2C data bus and many more electronic components. This circuit su
Logic Probe with Seven Segment Display
Logic probe is circuit that indicates the logic state of the node of any TTL logic circuit. It will work if we must supply the probe with the same power of..
Darlington Transistor Pair Logic Probe
Ideally, any testing equipment will not draw any current from the device under test. This ideal condition can be approximated by designing a testing device..
Coincidence Detector for Logic Signals
This is a coincidence detector circuit. This circuit is very useful for monitoring complex logic circuits. This circuit has two inputs, A and B. if A and B are..
Logic Probe Plans
This is a set of plans for an inexpensive, high performance digital logic probe that you can build in a few hours. It is small enough to use a plastic ball-point pen as a chassis, giving it a personalized touch and added style. The main advantage of this design is that the LED will only light when the probe tip is touching a voltage source (not fl
Logic Diagrams Services
The use of logic symbology results in a diagram that allows the user to determine the operation of a given component or system as the various input signals change. To read and interpret logic diagrams, the reader must understand what each of the specialized symbols represent. This chapter discusses the common symbols used on logic diagrams. When...
4 channel SQ logic decoder
Frequency counter Logic schematic
The lower schematic is a pretty standard bidirectional rectifier together with capacitors and a 7805 as a fixed 5V source which supplies all the electronic in the frequency counter. For "security reasons" a fuse is used. The upper diagram shows the main microcontroller, an ATMega161, connected to all the other boards via various cables. JP9 (reset
Nixie-clock using neon lamps as logic
The above shows my home-built digital clock. It uses Nixie-tubes for readout. In contrast to most other nixie-clocks being built these days, my clock does not use any transistor or IC for driving the tubes. Instead, the driving logic is built from neon lamps, together with resistors, capacitors and silicon diodes. The project started in 2002, whe
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