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AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
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Data Bus Circuits
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Current to Voltage
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RF Converter Circuits
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voltage to frequency
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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
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Regulated Power Supply
4 Band Resistor
5 Band resistor
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Automotive Alarm Circuits
Car Lighting Circuits
Car Parking Aid Circuits
Car Audio Circuits
Car Bike Circuits
Anti-theft car audio system circuit diagram
Anti-theft car audio system circuit is shown, which is taken from the car battery 12V DC power supply. When after closing the switch S1. Optocoupler IC1 light emitting diode is
555 car alarm circuit diagram
As shown is 555 more cars with alarm circuit, mainly consists of a 555 and a quad 2-input NAND gate circuit. At the time of low oil pressure and brake pressure is too low, the
Automotive electronic locks circuit
Automotive electronic locks circuit principle is shown in Fig. ICl dedicated lock IC 5G058, it O ~ feet respectively external key switch to the positive power supply, which is
Car active subwoofer
Between fixed loudspeaker that period. Its outer diameter must be consistent with the paper tube diameter to facilitate fixed speakers, and in its outer open on a walk trough,
Chizuru 100Hz channel frequency pulse charging electric bike battery circuit
Chizuru 100Hz channel frequency pulse charging electric bike battery circuit Shown as Chizuru 1.00 I-Lz letter frequency pulse electric bicycle battery charging circuit. Freque
Automobile wiper speed control circuit diagram
Circuit car wipers speed controller is shown in Fig. It can easily shake wiper speed between every second to ten times per second for any change, flexible and energy saving.
Classic car battery charging circuit diagram
Circuit principle : circuit after transformer, bridge rectifier and conditioning on the battery charge, the charge current transformer can be adjusted simply give about 12v 100
Car battery charging circuit diagram
Circuit principle: circuit after transformer, bridge rectifier and conditioning on the battery charge, the charge current transformer can be adjusted simply give about 12v 100A
This circuit has been designed to alert the vehicle driver that he/she has reached the maximum fixed speed limit (i.e. in a motorway). It eliminates the necessity of looking at the tachometer and to be distracted from driving. There is a strict relation between engine`s RPM and vehicle speed, so this device controls RPM, starting to beep and...
Motorcycle electronic Gear Indicator
This is a new design for a universal gear indicator that can be fitted to any motorcycle as an aftermarket accessory. Its main advantage is that its operation depends entirely on the gear shift lever movement, instead of connecting to speedometer and tachometer sensors (found in expensive commercial devices), which are rarely available in older...
Motorcycle Alarm Number 2
This circuit features an intermittent siren output and automatic reset. It can be operated manually using a key-switch or a hidden switch; but it can also be wired to set itself automatically when you turn-off the ignition. By adding external relays you can immobilize the bike, flash the lights etc. Ron has used my Asymmetric Timer as the...
This circuit was designed as an aid in parking the car near the garage wall when backing up. LED D7 illuminates when bumper-wall distance is about 20 cm., D7+D6 illuminate at about 10 cm. and D7+D6+D5 at about 6 cm. In this manner you are alerted when approaching too close to the wall. All distances mentioned before can vary, depending on...
LED driven tail/brake Light Cluster
This circuit was designed on request to drive a Light-cluster formed by several LEDs that can be mounted in the vehicle as a tail and brake light. When SW1 is on, the cluster will illuminate at medium brightness. When brakes are operated, SW2 will be closed and the cluster will shine at maximum brightness.
Wide Band Fuel Mixture Display
This document is an introduction to the Wideband Fuel Mixture Display (FMD). We modified the original Silicon Chip Fuel Mixture Display (that used a narrowband sensor) for use as a display for the DIY-WB wideband oxygen sensor controller. After first publishing how to modify the Jaycar KC-5300, we got Jaycar to make up the kits for us and we...
This project is a dedicated device. It dials a single phone number when the handset is lifted. There are two different modes of operation.. A slide-switch on the PC board allows the project to operate in automatic or manual mode. If the switch is in "auto dial" mode, a pre-programmed phone number is AUTOMATICALLY dialled when the phone is...
Bicycle back Safety Light
This circuit has been designed to provide a clearly visible light, formed by 13 high efficiency flashing LEDs arranged in a pseudo-rotating order. Due to low voltage, low drain battery operation and small size, the device is suitable for mounting on bicycles as a back light, or to put on by jogger/walkers.
Portable CD Player Adapter For Car
Whenever I`m in the car listening to my favourite CD, it always happens-my batteries go dead. To solve that problem, I built this extremely simple regulator circuit. It steps down the 12V from the lighter socket to 9V which is used by the CD player. Different CD players (I have a Sony Discman) may require different voltages, so just use the...
This device is a simple timer, allowing to keep on the headlights of your vehicle for about 1min. and 30sec., e.g. when accessing some dark place, without the necessity of coming back to switch-off the lights.
Wiper Speed controller.
Acontinuously working wiper in a car may prove to be a nuisance, especially when it is not raining heavily. By using the circuit described here one can vary sweeping rate of the wiper from once a second to once in ten seconds.
To simulate the Gyralite (dual flashing headlights).
This circuit must be connected to a 5 volt DC source. See my RR page for several 5 volt supplies. Note the flashing LED is optional, but looks s-o-o-o-o good on the top of a locomotive.
Multi-spark module for Electronic Ignition
Multi-spark ignition is very useful especially in the case of startings at low temperature and at low rpm range. Basic idea, is to apply to spark plugs instead of only one spark, a ?spark-burst? having big energy. In this case, combustion of air/fuel mixture is much better and the emissions are more reduced. In addition, through burning...
Car battery tester with LM3914
This circuit uses the popular and easy to find LM3914 IC. This IC is very simple to drive, needs no voltage regulators (it has a built in voltage regulator) and can be powered from almost every source. When the test button is pressed, the Car battery voltage is feed into a high impedance voltage divider. His purpose is to divide 12V to 1,25V (or...
Car 12V to +-20V DC converter
The limitation of car supply voltage (12V) forces to convert the voltages to higher in order to power audio amplifiers. This supply is intended for two channels with 50W max each (of course it depends on the amplifier used). Though it can be easily scaled up or the voltages changed to obtain different values. It is a classic push-pull design ,...
Car Alarm and Immobilizer
The alarm is "set" by opening Sw1. It can be any small 1-amp single-pole change-over switch - but for added security you could use a key-switch. Once Sw1 is opened you have about 10 to 15 seconds to get out of the vehicle and close the door behind you. When you return and open the door the buzzer will sound. You have 10 to 15 seconds to move Sw1...
Car battery Indicator (BC548)
The operating principle of the circuit is very simple. The first Led D1 is placed in series with the resistor R2 and diode D4.An only be lit this LED indicates that the battery is ypofortismeni. For this reason Led D1 is red. If the voltage is greater than 12V, then netting R5 Z3 turns the transistor TR1, so the glows and Led D2 indicates that...
Nite Rider LEDS
As a keen cyclist I am always looking for ways to be seen at night. I wanted something that was a novelty and would catch the motorists eye. So looking around at my fellow cyclists rear lights, I came up with the idea of 'NITE-RIDER'. NINE extra bright LED's running from left to right and right to left continuously. It could be constructed with...
Car Large capacitor charge controllers
One-farad capacitors require some care. It`s a common knowledge that they must be pre-charged with a current-limiting resistor before plugging in. It is less common knowledge that those fifty-dollar `smart cap controllers` are in fact very simple devices, two dollars for parts and labor. Here`s a basic cap switch that will connect capacitor to...
Audison LR604XR car audio amplifier
If the amp is built on bipolar transistors, and the preamp/crossover on FETs, then they were designed by different guys, right? Not this amp. Here, a strong, experienced designer`s hand is evident from schematic to parts layout, PCB routing and general assembly. Which leads to one of the lowest failure rates (don`t quote me on this although it`s...
Car Speed limit Alarm
This circuit has been designed to alert the vehicle driver that he has reached the maximum fixed speed limit (i.e. in a motorway). It eliminates the necessity of looking at the tachometer and to be distracted from driving. There is a strict relation between engine`s RPM and vehicle speed, so this device controls RPM, starting to beep and...
The circuit board and switches must be protected from the elements. Dampness or condensation will cause malfunction. Without its terminal blocks, the board is small. Ideally, you should try to find a siren with enough spare space inside to accommodate it. Fit a 1-amp in-line fuse close to the power source. This protects the wiring. Instead of...
Car Alarm and Immobilizer
This circuit features exit and entry delays, an instant alarm zone, an intermittent siren output and automatic reset. By adding external relays you can immobilize the vehicle and flash the lights. One of the inputs is connected to the vehicle`s existing door-switches. This provides the necessary exit and entry delays. It`s usually sufficient to...
HiJack car Alarm
This circuit is designed primarily for the situation where a hijacker forces the driver from the vehicle. If a door is opened while the ignition is switched on, the circuit will trip. After a few minutes delay - when the thief is at a safe distance - the alarm will sound and the engine will fail. Before fitting this or any other engine cut-out...
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