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SH-841 ASIC holiday lights
Figure 2-78 is SH-841 as the core device made holiday lights controller. By SCR VSl ~ VS4 to drive light string H1 ~ H4 flashes. Manifold operating voltage by AC by VD1-VD4 bri
SH-868 ASIC holiday lights
Figure 2-80 with the SH-868 is an integrated circuit made music flash circuit, which uses three battery power supply. Can drive flashing light emitting tube, while electronic m
SH-80051 holiday lights ASIC
Figure 2-85 is a single road SH-80051 produced flash string, SH-80051 chip only four ports: positive power supply terminal VDD; synchronization input zc; negative power supply
Blackout emergency lights circuit 2
Figure 282 foot another simple power outage should emergency lamp circuit. When the grid is often only power and municipal electricity by T Buck, VD1 ~ VD4 rectification, C- cr
advanced bicycle lighting Schematic
That Circuit is an advanced bicycle lighting system which will power your lights and also charge four NiCd batteries while you running in the streets, for keeping the lights on while the bicycle is stoped. Its fully automated without any switches.
Simple Infra-Red Transmitter/reciever Shematics
This 1 channel infrared transmitter/receiver remote control is the cheapest and simplest you can find. The transmitter transmits a sequence of pulses on 36 KHz frequency carrier. The diodes are Schottky type because of their low voltage drop (only 0.2V). The ripple counter 74HC4060 contains an oscillator which controls the frequency carrier to...
High-power battery-operated flasher
This flasher operates from a 12-volt car or boat battery. It offers 36 to 40-watts output, variable flash rate (up to 60 flashes per minute), independent control of both on and off cycles and photoelectric night and day control that turns the flasher on at night and shuts it off during the day for automatic operation. SCR1 and SCR2 form a basic...
SCR relaxation flasher
Flashing occurs each time the capacitor discharges through the tumed-on SCR. When the discharge current falls below the SCR holding current, the SCR turns off, and the capacitor begins charging for another cycle.
Astable flip-flop with starter
A pair of non-zenered MOSPOWER transistors, a pair of LEDs and a simple RC circuit make an easy sequential flasher with almost "unlimited sequencing timeâ€”from momentary to several seconds. The infinite input resistance of the MOSFET gate allows for very long sequencing times that are impossible when using bipolars.
Auto light controller
A 555 timer IC, operating in the one-shot mode, is triggered by light striking photoresistors. These normally have a resistance of several megohms but, in the presence of light, that resistance drops to several hundred ohms, permitting current from the six-volt source to flow in the circuit. The R-C combination shown gives an on-time of about...
Optical communication system
The circuit will modulate the light from the LED using a crystal microphone or a loudspeaker output. To obtain the maximum range, the optical system must be efficient (see example). Either a convex lens or a concave mirror can be used to convert the LED output into a parallel beam. The received light is concentrated onto a sensitive...
Multi-color LED driver
Have you ever wondered how many different colors can illuminate a LED? One, two or maybe three? Constructing this simple circuit, you will find it much more. The key component in this design is a dual LED. One such accessory includes two inside the 'slices' of different diode LED, that each of them produces a different color (usually green and...
Bar-graph indicator for ac signals
Indicator was designed for displaying the peak level of small ac signals from a variety of transducers including microphones, strain gauges and photodiodes. The circuit responds to input signals contained within the audio frequency spectrum, i.e., 30 Hz to 20 kHz, although a reduced response extends up to 40 kHz. Maximum sensitivity for the...
Led bar-graph driver
The circuit uses CA3290 BiMOS dual voltage comparators. Non-inverting inputs of A1 and A2 are tied to voltage divider reference. The input signal is applied to the inverting inputs.
Lamp flasher II
Brief full-power flashes are obtained when the SCR conducts during positive half cycles of the line voltage. The SCR fires when the voltage at the divider, R3 and R4, reaches the gate-firing level.
2 Kw flasher with photoelectric control
CR1, CR2, CR3, and CR4 form a bridge circuit with the SCR across the dc legs. With light on the photoconductor PCI, CI charges through Rl to about 150 Vdc. The resistance of PCI is low when illuminated, so very little voltage appears across it or C2. At about 90 volts CI starts discharging through Rl and the SCR, but the SCR cannot turn off...
A 555 timer, IC1, drives a 4017 CMOS decade counter. Each of the 4017's first four outputs drives a CA3079 zero-voltage switch. Pin 9 of the CA3079 is used to inhibit output from pin 4, thereby disabling the string of pulses that IC normally delivers. Those pulses occur every 8.3 ms, i.e., at a rate of 120 Hz. Each pulse has a width of 120 jis....
Low frequency oscillator-flasher
Electrolytic capacitors are unnecessary to generate a 1 cps frequency. As an scs triggers on, the 0.2 ÂµÂ¥ commutating capacitor turns off the other one and charges its gate capacitor to a negative potential. The gate capacitor charges towards 24 volts through 20 retriggering its scs. Battery power is delivered to the load with 88% efficiency.
High drive oscillator-flasher
The driver in the package is connected as a Schmitt trigger oscillator (A) where R1 and R2 are used to generate hysteresis. R3 and C are the inverting feedback timing elements and R4 is the pull-down load for the first driver. Because of its current capability, the circuit can be used to drive an array of LEDs or lamps.
Transistors Ql and Q2 are connected as a free running multivibrator. The output, at the emitter of Q2, drives the base of the common emitter amplifier Q3, which controls the lamp. This circuit configuration permits the flash duration, the interval between flashes, and the lamp type to be varied independently. Flash duration is proportional to...
Sequential ac flasher
This circuit uses a ring counter made up of Q3, Q4 and Q5. Q2 acts as an oscillator which triggers the SCRs Q3, Q4 and Q5 in sequence. When an SCR fires, a 0.2ÂµÂ¥ capacitor provides commutation, shutting off the previous stage.
Infrared transmitter II
The transmitter keyboard is arranged as a scanned matrix. The matrix consists of 7 driver outputs and 7 sense inputs. The driver outputs DRVON to DRV6N are open-drain n-channel transistors and they are conductive in the stand-by mode. The 7 sense inputs (SENON to SEN6N) enable the generation of 56 command codes. With 2 external diodes all 64...
Invisible infrared pulsed laser
The device generates an adjustable frequency of low to medium powered IR pulses of invisible energy and must be treated with care. The portable battery pack is stepped up to 200 to 300 volts by the inverter circuit consisting of Ql, Q2, and Tl. Ql conducts until saturated, at which time, the base no longer can sustain it in an "on" state and Ql...
Voltage regulator for projection lamp
The circuit will regulate the rms output voltage across the load (a projection lamp) to 100 volts Â±2% for an input voltage between 105 and 250 volts ac. This is accomplished by indirectly sensing the light output of lamp LI and applying this feedback signal to the firing circuit (Ql and Q2) which controls the conduction angle of TRIAC Q3. The...
Rugged lamp driver
This circuit is capable of driving filament lamps of nominal rating 200 mA at 60 V dc from a CMOS logic signal. The lamp or load is connected in series with the Darlington transistor TR1 and emitter resistor R5. The Zener diode ZD1 establishes a soft reference voltage on the collector of the optical coupler IC2.
When SI is on, power is applied to an oscillator composed of Ql, Rl, Cl, LI, and L2. Coil Ll is the primary winding of Tl, and L2 is the feedback winding. When Ql turns on, its collector current saturates Tl's ferrite core. That, in turn, removes the base drive to Ql through L2. Transistor Ql then turns off. As the field around Ll and L2 decays,...
Battery condition indicator
A 741 op amp is employed as a voltage comparator. The noninverting input is connected to zener reference source. Reference voltage is 5V. R2 is adjusted so that the voltage at the inverting input is half the supply voltage. When supply is higher than 10V, the LED will not light. When the supply falls just fractionally below the 10V level, the IC...
Precision battery voltage monitor
The precision voltage-monitor chip contains a temperature-compensated voltage reference. R1 divides down the battery voltage to match the built-in reference voltage of ICl (15 volts). When the voltage at pin 3 falls below 15 volts, pin 4 supplies a constant current of 7 mA to drive a small LED
Led bar-dot level meter
A simple level of power meter can be arranged to give a bar or dot display for a hi-fi system. Use green LEDs for 0 to 7; yellow for 8 and red for 9 to indicate peak power. The gain control is provided to enable calibration on the equipment with which the unit is used
Notes: LM3909, Capacitor, and LED are Installed in a White Translucent Cap on the Flashlight"s Back End. Only One Contact Strip (in Addition to the Case Connection) is Needed for Flasher Power
Dualxed cmos flasher
Inverters ICl-a and ICl-b form a multivibrator and ICl-c is a buffer. Inverter ICl-d is connected so that its output is opposite that of ICl-c; when pin 6 is high, then pin 8 is low and vice versa. Because pins 6 and 8 are constantly changing state, first one LED and then the other is on since they are connected in reverse. The light seems to...
Neon tube flasher
The voltage required to ignite the neon tube is obtained by using an ordinary filament transformer (240-6 V) in reverse. Battery drain is quite low, around 1 to 2 milliamps for a nine volt battery. The pulses from Ql, unijunction transistor, operated as a relaxation oscillator and are applied to Q2 which in turn drives Q3 into saturation. The...
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
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