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
PC Serial Port Receiver
PC Board Layout for Motion Detector
The GLMDPCB motion detector board is a double sided etched, screened and drilled printed circuit board designed for the GLMDA motion detector circuit shown in the schematic below. All or part of the circuit can be built. For some robotic and other special applications, only the amplifier and comparator circuits may be needed. The PIR325 sensor can
Build your own PC interface
TNC and Modems ruled the world of digital communications until recently. With the advent of high speed computing and digital signal processing (DSP) all this has changed. If you own a home computer (PC) with a sound card, all you need to do is download software and obtain an interface between the PC and your radio. The interface provides the audio
Migrating from x86 to Power PC
The first time you sign into developerWorks, a profile is created for you. Select information in your profile (name, country/region, and company) is displayed to the public and will accompany any content you post. You may update your IBM account at any time. The first time you sign in to developerWorks, a profile is created for you, so you need to
PC Controlled RC Car
This project article was originally written in 2004 when most computers had parallel ports. This is no longer the case, so much of this information is now outdated. The Mini RC Car Project has been one of my favorites to do. If you haven`t checked that project out, please read through that one before starting on your own. I`ve gotten a few e-mails
Designing The Low-Cost Mobile PC
A standard 12-volt auto electrical system can be considered to be a powerful but unreliable source of low-voltage DC current. Some of the features any mobile PC installation should provide include: Automotive systems must be designed to strict electrical standards. Your car`s starter motor, along with many of its accessories, are high-current...
PC based Robot Circuit
In order to create the circuitry below, you need a computer software that will control your parallel port. It will cost you about 30 US$. For example, a transistor (model number 2N2222) costs ~50, a DPDT relay, ~1. 75$ (this is maybe the most expensive piece, you need 7). This implementation uses IC-sockets to hold the pieces. That way, they are...
Alpine PXA-701/700 remote control & PC control
Just an early post to share some work on remote controlling the PXA-70x Multimedia controllers. Target For my new install, I have been looking at no..
USB Ultra IR-Receiver v2.0 to PC remote control and power ON - OFF
This Atmel IC, is clocked in the circuit with a 12 MHz quartz and provides a communication between the Infrared receiver and the PC, so that this signal can being processed by infrared receiver programs like Girder. As soon as a valid RC5 signal of the remote control arrives, a green low current LED with a 1. 5K resistance and the opto coupler with
DESKTOP 386SX PC AS DAQ (Data AQuisitor)
Chipmunk BASIC has lots off useful functions. So I wrote a small BASIC file to read the serial port and then plot the value on screen (Avaliable upon request FREE). The desktop 386SX PC has a 1. 44 FD and a 40M HD, a VGA with 256k of VRAM. BIOS was configure as no KERBOARD, so no keyboard is used. No monitor is needed either, but graphics card mus
PC based frequency meter
The simple circuit offers no isolation, but the simplicity of the circuit combined with cost of sound cards and the fact that diodes 1 and 2 add a good measure of protection makes this circuit ideal for the average user. Notice the physical hardware includes a 20MHz crystal oscillator module. This is not required to make the circuit work, but is i
200W ATX PC POWER SUPPLY
I bring you wiring diagram of PCs power supply of DTK company. This power supply has ATX design and 200W performance. I was drawed diagram, when I repaired this power supply. This power supply circuit uses chip TL494. Similar circuit is used in the most power supplies with output power about 200W. Device use push-pull transistor circuit with
FSK modem with driver for Atari ST or PC
DMX PC Keyboard Interface circuit
To be used with PC connected to video projectors, where the lighting controller may require control of a presentation on the video screen but the PC for the presentation is located in a different location to lighting control. The Hardware required for this project is quite simple see Circuit. The DMX data is converted inthe 75176 Bus Transceiver...
The PC Serial Port Receiver circuit
This circuit requires physical connections be made to the computer`s serial port (COM1 or 2). To the best of my knowledge, it is difficult to cause damage to yourself or your computer by improper connections to this port, but there is no guarantee that damage will not result. Use caution when making any external electrical connections.
PC FM Radio circuit
This is a fm radio receiver circuit which can be used with PC.PC radio REGULATIONSA) With the P1 we regulate the intensity of sound.B) With the P2 we regulate the frequency of reception.C) Optionally: If you want to check the frequency with your PC it will be supposed you make the following energies:- You assemble and the circuit that is in the...
cascading shift registers to drive 7-segment displays with PC input
Four 595s together to drive 7-segment displays and alsoadded code to acceptinput from the PC. Instead of using 10-LED bar graphs like I did last time, I`ve moved on to 7-segment displays - which are more challenging and provide a more meaningful output. The 7-segment displays I have are common-cathode, wired as shown below: The code to...
Battery Charger from PC Power Supply
PC Case USB LCD
For the first version of my Open Source Framework for USB Generic HID devices based on the PIC18F and Windows I made a quick example of how to use the library using a USB interface for an LCD. Now that I`ve completed the second version of the library I thought it would be fun to enhance the LCD project into a completely self-contained LCD module w
PC RLC Meter (BETA) Builders
PC Output Interface
The PC parallel port can be easily damaged by wiring mistakes, short circuits or the circuits you connect to it. If the parallel port is integrated into the motherboard, as is the case with most computers repairs can be expensive. You can buy inexpensive I/O card which connect to a spare slot on most motherboards, these are ideal for experimentors
USB Interface Circuits
Computer Interface 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