Top Circuits
-
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. http://www.next.gr/rf/antennas/active-antennas/.. -
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... -
This circuit use the CA3306 a family of CMOS parallel (flash) analogue to digital converters designed for low power, high speed applications. The CA3306CE operates at sampling rates up to 10 million samples per second and the CA3306E up to 15 million samples.... -
Chu Moy designed a very popular headphone amplifier that`s easy to build, and it can be built small enough to fit in a pocket, power supply and all. It`s powerful enough to drive very inefficient headphones to thunderous volumes from even weak sources, and.... -
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. The chip supports mute.... -
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... -
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. Although not perfect, this amplifier does have a wide frequency.... -
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. The device is designed to.... -
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.... -
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.... -
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.... -
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.... -
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,.... -
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. A voltage-slope.... -
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.... -
This encoder can generate up to 19,683 codes from 9 address lines by detecting 1,0, or open circuit. To initiate the transmit sequence, pin 14 should be pulsed low. The encoder will now output on pin 15 a data stream representing the condition on each of the.... -
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. High quality voice.... -
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. Unlike some other AM radio ICs, a minimum number of external tuned inductors.... -
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 composite video output can be injected directly into the video input of a receiver or.... -
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. Although not perfect, this amplifier does have a wide frequency....
-
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. Also the use of a.... -
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. Turning C3 with the help of C2.... -
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.... -
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, .. -
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 output is CMOS compatible (use a 3k3 pulldown resistor.... -
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. It has a microphone preamplifier and line level input and.... -
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.... -
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. The device can deliver.... -
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.... -
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.... -
By mixing an audio signal with ultrasound, you can hear the audio as if it's inside your head... even if the 'headphones' are nowhere near your ears. Patrick Flanagan invented the "Neurophone" over 40 years ago. His original patent (US3393279) was basically.... -
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.... -
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.... -
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 chip includes an RF input stage, mixer, local oscillator, IF amplifier/limiter, phase.... -
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..... -
You need free power? This schematic transforms the surrounding radio waves to usable current. The levels of power can be stepped up by using more diodes. The critical points in this device are first the type of diodes and second the antenna construction. The.... -
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. .. -
This preamplifier is requirement result of many friends to give a high quality preamplifier, capable to drive high quality power amplifiers with good sound, it`s not however difficult to making, it combines simplicity and handiness. It does not allocate a.... -
This structure is an amplifier RF, covering the range of UHF and intended for small TV transmitters, working in the channel UHF. The amplifier can enhance any video signal to the region UHF (450-800MHz). The circuit operates in class A and uses the known.... -
The dc motor is used as a generator with the voltage output being proportional to its rpm. The LTC1042 monitors the voltage output and provides the following control functions. If generator voltage output is below 13.8 V, the control circuit is active and.... -
The principle of operation is counting the pulse number derived from a constant frequency oscillator during a fixed time interval produced by another lower frequency oscillator. This oscillator uses the capacitor being measured as the timing. The capacitance.... -
This true SSB transceiver is built around just 5 vacuum tubes, with no transistors nor ICs. Superhet receiver with AGC and S-meter drives a loudspeaker, 5W transmitter, very stable VXO uses CB crystals to cover 20m ham band. A project for skilled RF.... -
There are still neighbors that keep annoying you by having loud the TV or the radio? Well I have you the solution. In fact all neighborhood will face your jamming waves at their TVs and radios, so be careful. This Jammer is the improved version of the old.... -
The simplified circuit [Fig.2] shows that each sub-amplifier consists of two voltage gain stages. The first stage consists of a complementary two stage common emitter [Q1-7] whose gain is about x2.3. The second stage is a current mirror stage [Q13-14] which.... -
This simple audio power amplifier was originally designed for a circuit board workshop, conducted by the OSU IEEE Student Group. At the workshop, 20 participants each constructed this amplifier, by etching and drilling the single sided circuit board,.... -
A medium power amplifier that is characterized by a lot of good sound quality, but simultaneously is very simple in the construction. Him uses, enough time in my active loudspeakers. In his output stage exist the very good FET transistors, technology.... -
An amplifier to drive low to medium impedance headphones built using discrete components. Both halves of the circuit are identical. Both inputs have a dc path to ground via the input 47k control which should be a dual log type potentiometer. The balance.... -
Audio-taper pot, R1, adjusts input level into two LM386 amplifier chips. The LM386 is a low-voltage audio power amplifier, designed to operate on 4V to 12V. It has an internal 15K feedback resistor between pins 1 and 5 which would set the gain at 20 (26dB)... -
The circuit use one simple, but good power supply, is enough its armor-clad by the remainder circuit, if it needs, with a aluminium, so that we avoid the noises. All the circuit can be placed in a small box, from which will only come out the RCA jack, the.... -
This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum pick-up and connection to the amplifier is more.... -
The transmitter was designed with redundancy and cutback (reduced power mode) in mind, giving the transmitter more continuity of service. The final amplifier was divided into 3 separate modules, each using four RCA type UV-898 tubes in push-pull parallel.... -
The circuit has a "floating" output, i.e., it behaves like an isolated transformer winding, with the output amplitude remaining unchanged whether the center or either end of the load is grounded. This is achieved by making Z-out, common mode, infinite. The.... -
In recent years more and more, have a tendency ket demanded higher reimbursement structures with lights and music lovers in general and manufacturers of tube amplifiers. The reason, in their view is that the sound of tubes is more sweet, how rich and.... -
The circuit provides a clean, stable square wave and it will operate on anywhere from 6 to 15 volts. The IC and color-burst crystal are the kind used in TV receivers... -
The Clock Controller was designed to be an exemplary of using 'C' language to control timer0interrupt, 7-segment LED and keypad scanning. It provides 1-bit sink currentdriving output, for driving a relay, opto-triac, say. Many projects requiring7-segment.... -
The circuit provides a 10MHz cutoff frequency. Resistor R3 ensures that the input capacitance of the amplifier does not interact with the filter response at the frequency of interest. .. -
I wanted to do some time lapse photography where the camera would take 1 capture every 20 minutes or so of a race car chassis fabrication project. After looking around on the web, I decided the GoPro Hero2 would work. The GoPro has a built-in time lapse.... -
A pattern generator is a very useful instrument for the correct alignment of the timing circuits of a television set. The circuit we propose you to build, is a «bar generator» that will produce horizontal and vertical stripes (bars) on the TV screen, that.... -
The circuit here is a A/D converter, that consisting of A2, a flip-flop, some doors and a current sink, is based on a current balancing technique. Again, the stabilized LTC 1052 50 no drift of V input 1 ° C is necessary to eliminate the offset errors of.... -
Rear channel "ambience" can be added to an existing stereo system to extract a difference signal (R - L or L - R) which, when combined with some direct signal (R or L), adds fullness, or "concert hall realism" to the reproduction of recorded music. Very.... -
An application, which is considered, of very good quality sound since the entrance transistors are working at Class A. The quality of sound depends to a large extent on IC1, which must be of good quality. It can be chosen from several IC with the best from.... -
The circuit is based on the known chip TDA1524, which is an integrated control Volume, Bass, treble, and Balance. These arrangements are made through 4 potentiometers (P5-P8) with trend. The integrated circuit IC1, to run the needed very few external.... -
A lot of friends ask me a circuit AUDIO MIXER, for various uses. I will begin with a circuit which you can it manufacture, as you want. This you can place in the MODULES of inputs any circuit you want, depending on the use that you intend the MIXER, the same.... -
The mixer circuit below has 3 line inputs and 3 mic inputs. The mic inputs are suitable for low impedance 200-1000R dynamic microphones. An ECM or condenser mic can also be used, but must have bias applied via a series resistor. As with any mixer circuit, a.... -
On this page three adjustable notch filters configurations are shown . They can be used in your small pre-amp or amplifier project to filter out any HUM at 50 Hz ( European ) or 60Hz . By sustituting the capacitors values in the bridge other frequencies can.... -
A 'TV modulator' is really no more than a transmitter. It is a very small transmitter, admittedly, but none the less that is what it is. What does a modulator actually do? In general -and this design is no exception to the rule - it is a simple oscillator.... -
In this fast-paced world, there is little time for inconveniences and a greater need for portability and adaptability. The idea for an Audio/Video transmitter stems from this need. There may have been times when you`ve wanted to hook up your VCR from one.... -
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.... -
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.... -
The circuit generates a warble-tone alarm signal that simulates the sound of a British police siren. IC1 is wired as an alarm generator and IC2 is wired as a 1 Hz astable multivibrator. The output of IC2 is used to frequency modulate IC1 via R5... -
This power supply is dedicated for use with rf equipments like, linear amplifiers, transmitters, receivers, and in every application that clean an-noisy signal is required. The circuit is very simple and you can drive it with a 220V/18V/3A transformer at the.... -
I just finished a half duplex serial asynchronous link from a simple PIC circuit to the RCX. It is able to receive codes from the RCX (or Lego RCX remote control) store them in RAM & EEPROM and transmit any IR op-code to the RCX in turn. Included in the.... -
Inverters Ula and Ulb are connected in a simple RC oscillator circuit. The frequency is determined by the values of Rl, Cl, C2; and the internal characteristics of the integrated circuit. As long as the circuit is oscillating, a positive dc voltage is.... -
The circuit uses a 741 op amp operating as an inverting amplifier to amplify the voltage produced by an 8-ohm speaker used to detect any sounds. The feedback resistor R3, a 1-megohm potentiometer used to vary the gain of the amplifier determines the.... -
The circuit is quick and easy to put together and install, and tells you when battery voltage falls below the set limit as established by Rl (a 10,000-ohm potentiometer). It can indicate, via LED 1, that the battery may be defective or in need of change if.... -
So you`ve read about my Computerized Room or have seen those nifty home automation products advertised in the back of electronics magazines? Or perhaps someone you know has done something similar. At any rate, you have decided to try it yourself. The first.... -
This adaptor will capture plots or prints of your GPIB instrument to your PC through the serial port. It fills the need of anybody who has a test instrument with the GPIB port and likes to get the screen dump on his PC without any GPIB card. Project based on.... -
This design used to measure air or gas flow works by measuring the energy required to maintain a heated resistance wire at constant temperature. The positive temperature coefficient of a small lamp, in combination with its ready availability, makes it a good.... -
The diode rectifies the ringing signal to supply the operating power to the audio relaxation oscillator made up of LI, L2, Rl, R2, and C. Moreover, L2 together with Ql acts as an opto-isolator, totally isolating the telephone line from the rest of the.... -
By adjusting the oscillators so their frequencies are very nearly the same, the difference between them is made audible as a beat note, this beat note changes slightly when the search loop is moved over or near to a piece of metal. It has been found in.... -
This battery-powered metal detector uses four exclusive-OR gates contained in the 4030 CMOS integrated circuit. The gates are wired as a twin-oscillators and a search coil serves as the inductance element in one of the oscillators. When the coil is brought.... -
In the early `80s, I read some articles on LED arrays. They described using arrays of 64 or more LEDs as crude oscilloscopes and other interesting things. I decided I`d make one myself - a really big array, 256 LEDs arranged as 16 columns by 16 rows. In.... -
Timer Ul operates as a free-running oscillator at 60 Hz, providing trigger pulses to timer U2 which operates in the monostable mode. Resistor Rl is fixed and capacitor Cx is the capacitor being measured. While the output of U2 is 60 Hz, the duty cycle.... -
The Generator cell must have reasonable surface area on the Plates to generate a reasonable amount of Hydrogen/Oxygen. And a Typical construction would use Stainless Steel for the Electrodes to prevent them from being Quickly eaten away... -
With the coupler biased in the linear region by the 10 mA dc bias on the IRED and the voltage divider on the phototransistor base, photodiode current flows out of the base into the voltage divider, producing an ac voltage proportional to the ac current in.... -
The circuit charges a 9-V battery at about 30 mA per input ampere at 0.4 V. Ul, a quad Schmitt trigger, operate as an astable multivibrator to drive push-pull TMOS devices Ql and Q2. Power for Ul is derived from the 9-V battery via D4; power for Ql and Q2 is.... -
This is a positioning servo drive featuring adjustment of balance, gain, and deadband. In addition to control from a dc signal, mechanical input can be fed into the balance control, or that control could be replaced by a pair of resistance transducers for.... -
This 115 Vac, electronic circuit breaker uses the low drive power, low on resistance and fast turn off of the TMOS MTM15N50. The trip point is adjustable, LED fault indication is provided and battery power provides complete circuit isolation. The two.... -
The comparator has an output pull-up resistor RL and is connected up to operate as a Schmitt trigger using the single rail supply Vcc. The feedback resistors Rl and R2 give upper and lower threshold levels VT+, VWxw, respectively. VT+ is easily set by.... -
This circuit was designed to make switching of a 48-channel mobile transceiver safe to operate while mobile. The oscillators allow for single-stepping or a scanning function. The scan facility allows for stepping through all 48 channels to check for.... -
Here's an effective little combination lock that you can put together in one evening's time. To open the lock, simply dial in the correct combination on the three rotary or thumbwheel switches. With the correct combination entered, current flows through Rl.... -
This transmitter was designed from the ground up to provide very high sound quality, coupled with excellent frequency stability, reliability, etc. It can be used as a standalone transmitter to serve a medium-sized town, or as an exciter to drive a.... -
A filter with a band-reject characteristic is frequently referred to as a notch filter. A typical circuit using a µ 741 is the unity-gain configuration for this type of active filter shown. The filter response curve shown is a second-order band-reject.... -
The purpose of the Kapagen is to suck the free electrons from the Earth. The Earth is a big capacitor which contains free electric charges. If it is possible to create or to find a potential imbalance between two points in the ground, it seems possible to.... -
This circuit operates as an oscillator and a timer. The 2N6028 is normally on due to excess holding current through the 100 k resistor. When the switch is momentarily closed, the 10 µ¥ capacitor is charged to a full 15 volts and 2N2926 starts oscillating.... -
The inexpensive 7404 hex-inverter has enough amplification to handle a wide range of transducers. Closing the key completes the battery circuit and applies four to five volts to the 7404. Bias for the first two inverter amps (Ula and Ulb) comes from the two.... -
If the input frequency is known, the timer can easily be used as a frequency divider by adjusting the length of the timeing cycle. Figure shows the waveforms of the timer when used as a divide-by-three circuit... -
This amplifier has a high quality circuit that includes full sort circuit protection and very low T.H.D. at full range of frequency. It needs simmetrical power supply +-40V. The power transistors at the output are connected as DARLINGTON and both needs.... -
The gain of the low-cost IC is internally fixed so that it is not less than 34 dB (50 times). A unique input stage allows input signals to be referenced to ground. The output is automatically self centering to one half the supply voltage. The output is also....