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
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
tape head preamplifier with LA3161
The Stereo Tape Head Preamplifier kit is based on LA3161 IC from SANYO. Power supply - 9 ~ 12 VDC @ 20 mA. Output power - upto 200 mW. Input Resistance - 100 K? (Typ), Load Resistance - 10 K? (Typ). Low noise, good ripple rejection owing to the on-chip voltage regulator. Berg pins for connecting power supply, input and output. Power-On LED...
All transistor microphone pre-amplifier
The microphone has high sensitivity in the audio range, but in the ultrasonic range, the sensitivity decreases rapidly. The receiver is very sensitive. To prevent overdriving and feedback due to the high sensitivity of the microphone in the audio range, the gain of the amplifier should be low in the audio range and increase with frequency in the...
Hi quality Phono Preamplifier
In recent years, following CD`s introduction, vinyl recordings are almost disappeared. Nevertheless, a phono preamplifier is still useful for listening old vinyl discs from a well preserved collection. This simple but efficient circuit devised for cheap moving-magnet cartridges, can be used in connection with both audio power amplifiers shown in...
Audio Line preamp Driver
This preamplifier has a low output impedance, and is designed to drive long cables, allowing you to listen to a remote music source without having to buy expensive screened cables. The very low output impedance of around 16 ohms at 1KHz, makes it possible to use ordinary bell wire,loudspeaker or alarm cable for connection.
Simple Phono Preamplifier
Simple circuitry suitable for moving-magnet cartridges Passive high-frequency equalization. This simple but efficient circuit devised for cheap moving-magnet cartridges, can be used in connection with the audio power amplifiers shown in these webpages, featuring low noise, good RIAA frequency response curve, low distortion and good high...
The Sound Blaster 16 PCI and Sound Blaster 16 ISA do not have a very sensitive microphone input. This little one transistor amplifier is powered directly from the microphone jack on the sound card and has LOTS of gain. Just put a 100uF bypass capacitor in parallel with the diode to increase gain even more.
low pass filter subwoofer
The acoustic filters are met in various points in the sound systems. The knownest application they are the filters baxandal for regulating tone low and high frequencies and filters crossover where the acoustic region is separated in subareas, in order to it leads the corresponding loudspeakers. The application that to you we propose is a simple...
Since the volume control is after the gain stage, the preamp can be easily overloaded. I tried to limit the input signal by mounting a 470 k resistor in series with the CD input. A voltage divider is formed by this resistor and R107, resulting in a greater than 5-fold attenuation of signal input to the gain stage. Although the distortion had now...
Microphone balanced preamplifier
A professional suggestion for those interested in improving sound. The circuit constitutes the part of input mixing console sound from the microphone or source of high level . It can be used on it's own or be multiplied to the number of channels required. It includes all the useful functions such as, phantom power , reverse face, signal...
Tube Preamplifier with ECC88
A very good circuit of pre-preamplifier, for amplification of signals from heads of Moving Coil. It uses the two departments of tube ECC88, association parallel, for reduction of produced noise. The circuit enters in line with existing circuit PHONO. Switches S1-2 make adaptation of entry in the impedance, of expense of head. The Positive is...
Stereo Preamplifier and Bass-booster
This preamplifier was designed to cope with CD players, tuners, tape recorders etc., providing a gain of 4, in order to drive less sensitive power amplifiers. As modern Hi-Fi home equipment is frequently fitted with small loudspeaker cabinets, the bass frequency range is rather sacrificed. This circuit features also a bass-boost, in order to...
Microphone Preamplifier LM833
This design was born of frustration with the mic preamp in my Sony R91. It clips at ridiculously low levels, basically it has 28mV of headroom to deal with an input that could be as high as 1800mV (depending on mic & volume), so this design attempts to cure that by : A: Providing a higher electret bias voltage, 9V through a 10k resistor to give...
Telephone Headphone amplifier
A compact, inexpensive and low component count telecom head- set can be constructed using two readily available transistors and a few other electronic components. This circuit is very useful for hands-free operation of EPABX and pager communication. Since the circuit draws very little current, it is ideal for parallel operation with electronic...
Microphone Preamplifier BC547B
This is a simple microphone preamplifier circuit which you can use between your microphone and stereo amplifier. This circuit amplifier microphone suitable for use with normal home stereo amplifier line/CD/aux/tape inputs. This microphone preamplifier can take both dynamic and electret microphone inputs (preamplifier provides power foe electret...
Line signal to phono adaptor circuit
Many amplifiers have phono inputs for connecting record players to the amplifier. Phono input is designed to take a up to few millivolt signal from phono pickup and amplify it. The amplifier stage does also some equalization based on standardized RIAA curve. That RIAA equalization is used in the playback to reduce the high pitch noise and...
PC Microphone Preamplifier
Soundblaster soundcard series (SB16, SB32, AWE32 and AWE64) have all a microphone input designed to be used with the electret microphones which come with the soundcard package (some packages) or with separate microphone designed to be used with SoundBlaster soundcards (there are separate microphones and some monitors have built-in microphones...
Selectable sensitivity Preamplifier
Most audio amplifier systems must have preamplifiers with many different characteristics. These include high-gain linear response for magnetic microphones, low-gain linear response for tuners, and high-gain RIAA equalization for magnetic phone cartridges. To meet this broad requirement, most amplifier designers include a single universal...
Lm318 Microphone preamplifier with tone control circuit and explanation
This electronic project is a simple microphone preamplifier based on the LM318 op amp. The LM318 op amp is operated as a standard non-inverting amplifier. Resistor R1 provides an input path to ground for the bias current of the non-inverting input. The combination of R2 and C2 provides a frequency roll-off below 30 Hz. At 30 Hz and above the gain
LA3161 based Preamplifier circuit with explanation
Preamplifiers are used to amplify low level signals such as those from mikes, tape heads before they are fed into power amplifiers. Power amplifiers are generally less sensitive. Frequency response also can be suitably trimmed and modified at preamp stage. LA 3161 is one of those widely used in tape decks and amplifiers as a stereo preamplifier. B
pre amp single supply
unbalance pre amp single supply. The use of a single power supply requires the presence of a voltage equal to the voltage divided by two. This half-voltage is created by the resistors R9 and R10 connected in voltage divider bridge.
Electret mic pre amp
Electret mic pre amp schematic. The op amp provides an amplification of about 30 dB (which is sufficient for the relatively high output level of an electret microphone), this gain depends on the value of resistors R3 and R4. If you want to be able to vary the gain, simply replace the resistor R4 to 120K a 470K potentiometer in series with a resist
Hydrophone preamplifier circuit
Hydrophone preamplifier circuit. As you can see, it`s really simple and uses only conventional components. The transducer used, is piezo type and has a relatively high output impedance, which requires a preamp with a high input impedance.
Mic pre amp
Mic pre amp schematic based TLC251. TLC251 is a Programmable Low-Power Operational Amplifiers. This is indeed a control input, called BIAS (pin 8), which determines the mode of operation. When the pin is worn on the positive potential of power supply, the consumption of the circuit is reduced to a minimum, which is 10 uA (ten micro-amps).
Mono preamp based on a NE5534
Mono preamp based on a NE5534 circuit diagram. This preamp is particularly suitable for microphones with an output impedance of 200 ohms to 600 ohms. The advantage of the preamplifier is 50 dB, and bandwidth (-3 dB) extends to about 25 KHz. The splitted power supply is required.
Low impedance pre amp circuit diagram
The amplification of this pre amp is therefore very high, whether to reduce, there should be a trimmer R3 series to 100 ohms. The system can be powered by a voltage of between 9 and 18Volts. for its realization, follow the diagram layout.
Preamplifier for magnetic phono cartridges schematics
Circuit IC1 provides a do amplification of 40 dB, which drops to about 20 dB when the frequency rises above 500 Hz. To minimize the (resistor) noise and the load of the op amp at higher frequencies, the value of R3 is a compromise. The associated polystyrene capacitor, C2, should have a tolerance of 1 to 2%. To raise the 2-mV output of the dynamic
Preamplifier + tone control circuit based TDA1524A
Preamplifier + tone control circuit based TDA1524A. Tone control circuit module is included in this preamplifier circuit, so you can connect the output channels directly to stereo power audio amplifier circuit. ThisRIAA stereo preamplifier uses only conventional components, you can easily find components at electronics store. The circuit is intend
Bootstrap Buffer Based Preamp
I have been playing with a number of variations of the circuit as a free standing preamp, headphone amp, 321/729 replacements and as a potential active crossover, any and all of which may happen if there is demand. There has been strong interest in all of the threads and my bootstrap buffer preamp is up and running nicely - and for the moment it`s
14Watt Audio Amplifier + pre-amp and tone control
Condenser Mic preamplifier
Vacuum Tube Preamplifier Analysis and SPICE Simulation
The concept of an AC model for the triode is presented and the equivalent circuit technique is described. Theoretical calculations for amplifier gain and frequency response are derived and compared to simulation results in the SPICE3 environment where good agreement is shown. The characteristic properties of AC and DC signals are apparent from fun
Servicing the Hammond B-3 Type Pre-Amp
Designed in the fifties, this pre-amp remained in production until 1975. And, it remains fully functional and serviceable today. This discussion is designed to help owners do some basic troubleshooting and, we`ll get into some depth of circuit operation as well as common problems usually found here. If the vibrato switches are set to vibrato off,
Audio Filters Circuits
Audio Amplifier Circuits
Audio Oscillator Circuits
Audio Mixer Circuits
Audio Equalizer Circuits
Audio Tone Balance Circuits
Beeper Buzzer Circuits
Vacuum-Tube Valves Circuits
Musical & Effects 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...
Digital Signal Integrity
Interconnection and Timing of Digital Circuits
CMOS Circuits Tutorial