Latest Submited Circuits/Schematics

That RF Amplifier is for boosting small fm transmiters and bugs. It use two Philips 2N4427 and its power is about 1Watt. At the output you can drive any linear with BGY133 or BLY87 and so on. Its power supply has to give 500mA current at 12 Volts...

A stereo power amp designed for use in portable players and radios. A 3V supply can be used to drive headphones providing 20mW in 32 Ohms per channel, and a 9V supply will provide 1W in 8 Ohm per channel for small loudspeakers...

A power amp designed for use in low voltage, especially battery-operated, applications. For minimum parts count, C1 and C2 can be omitted. With pins 1 and 8 open circuit the gain in internally set to 20 dB...

Nice small audio amplifier which use only few parts to give good quality sound. This amp can be used as a simple booster, the heart of a more complicated amplifier or used as a guitar amp...

A very useful audio amp in an 8-pin DIL package. The IC features a very low minimum working supply voltage of 3V, low quiescent current, good ripple rejection, no crossover distortion and low power dissipation...

That circuit is based at a technique to remove or neutralize the salt in water, and protect the pipes at home as well as the washing machines or our selves from salt. Its called water softener and its automated circuit using two 555 timers...

This is a nice 2 Watts FM transmitter. It has a Super-Sensitive pre-amplification with BC109 and BC177 with more than 100% signal modulation. The job finish the 2N2219 by Motorola. Feed input from a simple cd player or PC (win amp) or just connect a microphone...

The Circuit shown can transmit voice to exceptionally good range. Tune trimmer to hear the signal to your near radio. Frequency range is 88-108 MHz. Max current consumption is 30mA...

The TDA7294 is a Hi-Fi amplifier and can give 100W RMS but with 10% distortion. Supplying 30 Volts you can have 50 Watts RMS with 1% distortion. Frequency range start at 16Hz and can reach 100KHz. Make sure you are using good heatsink...

This device can be very illegal if you attach an external antenna so don't. adjust frequency by turning trimmer. It is intended only as a practical joke device...

This is a high quality power supply with a continuously variable stabilized output adjustable between 0 and 30VDC. the LM 723 is the heart of the power supply which drives the BD137 and then the 2N3055. The circuit provides short circuit protection...

The schematic shown, is a 2 transistor signal amplifier between 10 MHz to 30 MHz. The BF256C and the BF494 are very popular transistors and are easy to find. The transformer works as insulator and amplifier...

The schematic shown, does no need any power supply because is a simple low frequency passive filter. It could be usefull if you want to drive an extra subwoofer from your stereo system...

That circuit protects the overdriven signals going into an amplifier. Instead of a zener diode we use a transistor. That way we ensure that the above the ordinary input voltages ( 1 volt r.m.s.) can be acheaved without distortion...

This circuit switch slowly on and off the internal lights in a car. The delaying time can be adjusted changing the values of the 10k, 4M7 resistors and capacitor...

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...

This active antenna schematic can be used to frequency range from 10 KHz to 100 MHz. The length of the Antenna can be between 0.5 to 1 meter long. The power consumption is 20-30mA...

The antenna tunning circuit can accommodate 1/2 wave length antennas or higher, for input resistances of 50 Ohms which make it suitable for CB (Citizen Band) transceivers. C1 is for fine tunning and C2 is just for tunning...

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...

That Circuit is a UHF TV linear amplifier for small TV transmitters with output aroun 100-200mW. The transistor BGQ136 comes with SOT-122 case has gain of 13dB at 800MHz. So with input 100mW you get 2W output and for 200mW you get 4W...

This small circuit is a Linear amplifier for driving small UHF TV transmitters. Its gain is 7dB and can amplify a signal between 450-800 MHz. You can drive the circuit with 1 to 1,5 Watts signal. Better use double layer PCB with the second layer connected to earth...

This circuit converts surrounding radio frequency waves to electric power. It can provide 40 Volts at 10 Watts indefinitely. The output power can be improved playing with the antenna. Placing the antenna near large metal objects gives more power...

An ultra low noise audio preamplifier particularly suited to microphone preamplification including balanced microphones. The IC features wide bandwidth, low distortion only 0.007% at a gain of 100, and very low noise only 1.3nV/Hz for source impedance s up to 4kohm...

The LA9472A is a 2A monolithic step down switching regulator operating in continuous mode and realized in a new BCD technology allowing the integration of isolated, vertical DMOS power transistors with mixed CMOS/bipolar transistors...

A monolithic phase locked loop for data communications. The IC contains a basic phase locked loop for tracking an input signal within the pass band, a quadrature phase detector which provided carrier detector and an FSK voltage comparator which provides FSK demodulation...

A PAL color encoder and video summer which requires just composite sync and composite blanking inputs, and a 6-bit binary coded input giving the color information...

This Circuit uses the ZNA234E IC which makes available all the waveforms necessary to produce the crosshatch, dot and greyscale test patterns on a television screen...

The 555 is a highly stable device for generating accurate time delays or oscillation. Aditional terminals are provided for triggering or resetting if desired. In the time delay (monostable) modeof operation the time is precisely controlled by one extrernal resistor and one capacitor...

A high performance op-amp that sets a new standard of excellence in noise performance only 0.9nV/Hz with low source resistances. Total harmonic distortion is less than 0.01%. The op-amp is suitable for use in high quality audio, low noise frequency synthesizers, infrared detectors etc..

A simple sound generator IC that can produce four sound effects. Designed for use in toys, the effects are selected by varying the connections to pins1 and 6 as follows...

TheCA3189E is a comprehensive FM-IF system designed for high fidelity FM tuners. It includes a three stage FM-IF amplifier/limiter configuration with level detectors for each stage, a double-balanced quadrature FM detector and an audio amplifier that features the optional use of a muting circuit...

A triac controller for switching resistive loads directly from the mains supply using the zero crossing technique. The device is powered directly from the mains via a diode and dropper resistor, and the IC has its own regulator to limit its supply to 9.25V...

The IC is ideal for detecting the presence, absence or level of water or other conducting liquids. A detector determines the presence or absence of fluid by comparing the resistance of the fluid with the IC's internal reference resistance. An AC signal is used to prevent plating of the probe...

A humidity sensor with temperature compensation built-in. Never apply a DC voltage to the sensor, even measuring the sensor with an ohmmeter will damage the device, always ensure that an AC voltage is applied. Avoid condensation, freezing, dust, mist, oil, alcohol, etc...

A large area photodiode and current to frequency converter combined in a clear plastic 8-pin DIL package. The output is a pulse train whose frequency is directly proportional to the light intensity. The photodiode has a wide dynamic range, high sensitivity and high noise immunity...

The MAX712 and MAX713 are nickel cadmium (Ni-Cd) battery fast charge controllers which will fast charge batteries from a DC source at least 1V higher than the maximum battery voltage. 1 to 16 series cells can be charged at rates up to 4C...

This circuit uses the TDA2040V which is a monolithic power amplifier IC intended for use as a high quality, class AB audio power amplifier. Typically it provides 22W output power into 4ohm with 0.5% distortion, from 32V supply. It provides a high output current and has very low harmonic and crossover distortion...

This circuit uses a stereo amplifier IC in a 14-pin DIL package that requires very few external components to make a complete 2 Watt per channel power amplifier. The LM1877N-9 is suitable for use with 8ohm or 16ohm speakers...

This Circuit is based on the UM5100 which can record speech into a digital memory and then play it back. The device is designed to be used directly with static RAM's up to 256K bits, or with EPROM 's or ROM's for playback only. The bit rate is adjustable from 10kbs to 28kbs with higher quality at faster bit rates...

That circuit uses the MSM6322GSK which is only available in small 24 pin plastic SOP style package. A speech pitch converter IC that operates in real time and requires very few external components. In addition there is a build-in 8-bit A/D converter and 9-bit D/A converter...

This reciever uses the TDA1072A which is a complete AM reciever on a chip and it only requires comparitively few peripheral components to complete a high quality AM radio Circuit. Only two of these, an RF input transformer and a single winding oscillator coil need be tuned either capacitively or inductively...

This Circuit is based on the LM3876. A 11-pin plastic package IC with high performance audio power amplifier, an output mute function which can be used to eliminate switch-on and switch-off "thumps" to the loudspeaker load. It is capable of delivering 40W continuously into 8ohm load, and is fully protected using established techniques...

This encoder can generate up to 19,683 codes from 9 address lines by detecting 1,0, or open circuit. If pin 14 is held low, the output will be continuous, otherwise two identical words are output for each pulse on pin 14. A 1 is transmitted as two long pulses, a 0 as two short pulses, and an open circuit as a long pulse followed by a short pulse...

This circuit is based on a preprogrammed multi-instrument melody generator IC, containing a 512-note memory capable of generating 16 tunes. The comprehensive control facilities enable playing - all tunes repeatedly or stopping at the end, - or one tune repeatedly or stopping at the end...

At this circuit the SSM2044 IC is used, a 4 pole voltage controlled filter designed for electronic music applications. On-chip voltage control of resonance allows direct and easy interfacing with programmers and controllers. The IC features extended control range, low noise, and high control rejection...

That circuit is based on a 14-pin DIL IC capable of producing sine, square, triangular, sawtooth and pulse waveforms of high accuracy and stability. Sweep range can be up to 40:1 or 1000:1 with a little less quality...

This circuit use the CA3306 a family of CMOS parallel (flash) analogue to digital converters designed for low power, high speed applications. An overflow input allows two devices to be connected in parallel will permit conversion speed to be doubled...

An FM radio on a single chip requiring only a few simple peripheral components. In particular the ship requires only one simple coil and alignment is very easy. The output will directly drive a crystal earpiece or could be used with a TBA820M to form a complete portable radio...

This very high quality audio amp is based on the TDA1514A, a 9-pin flat package IC. The heatsink must be insulated from ground. The amplifier will deliver 40 watt into an 8ohm load with a 27.5 volt power rail or 40 watt into 4ohm load with a 21 volt power rail...

This circuit uses a high quality audio amplifier IC in a 5-pin TO220 package that does not require insulating washers between the metal tab and heatsink in single rail supply applications. The amp can provide 32 watt rms into 4ohm load and 25 watt rms into 8ohm...