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Balanced Microphone Preamplifier
The preamplifier is intended for use with dynamic (moving coilMC) microphones with an impedance up to 200 ? and balanced terminals. It is a fairly simple..
FM Wireless Microphone
Here is a very simple, inexpensive and interesting project which provides lot of fun to a home experimenter or hobbyist. This simple transmitter can trans..
Low-Noise Microphone Amplifier (OP270E)
The signal from a microphone is two weak for a standard line input. This low-noise DC-coupled microphone amplifier provides a solution for anyone who want..
Portable Microphone Preamplifier
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 simple, due to the absence of mains cable and power supply. Using a stereo microphone the ci
Powering Electret Microphones
I want to power a condenser MIC ( Electret 2 terminals ). I connected a resistance of 1k and capacitance of 10uf to its positive terminal and grounded other te..
Dynamic Microphone Preamplifier using C945 transistor
It use the three transistor (2SC945, or 2C1815 or 2SC828) is main Which typical transistor amplifier with a low noise this circuit, too. There are about 200-300 times the gain. The frequency response is 50Hz to 100KHz. I have an old microphone, I want to make play with common amplifier. It does not sound much. Must to use pre amp before. I...
Pre MIC (microphone preamplifier) 2 CH by IC NE5532 or LF353
This be Pre Mic circuit or Microphone preamplifier circuit model 2 CH. By this circuit uses integrated number circuit NE5532 or LF353. It perform enlarge sound signal from Dynamic Micro phone give the power goes up for subsequently submit to go to still stereo power amplifier circuit next. This circuit be of good quality good sound, because of use
ambient noise cancelation microphone circuit will work
A microphone to listen to a wristwatch and want to cancel the ambient noise in the room. I have included a circuit that I plagiarized from a headphone cancelation circuit. Will this circuit that I have drawn here work. Whoops forgot to include the Schematic I will have it up in a minuite Why not just do what aircraft noise-canceling microphones...
Electret Condenser Microphone Amplifier
Amplifier circuit for electret microphones (condenser microphones). Amplifier the audio signals picked up by the electret microphone, using 741 op-amp and a 2N2222 transistor..
Electret microphone amplifier circuit design using transistors
This electret microphone amplifier is designed using common electronic components. This microphone amplifier uses an electret microphone capsule, but can be an dynamic microphone, which have a low resistance. This circuit requires a supply voltage between 5 and 10 volts, is recommended to use a supply voltage of 9 volts DC. Since the circuit has
High gain microphone preamplifier electronic project
This microphone preamplifier electronic project is based on transistors and is capable of about 70dB or more gain at audio frequencies. Gain of this circuit is approximately equal to the product of the hfe of the both transistors times in the ratio of the load resistance to the input resistance of the preamp. As an approximation, these resistan
LM318 microphone preamplifier circuit design
This simple microphone preamplifier is 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 is relatively flat a
OP37 low noise microphone preamp circuit design electronic project
This microphone preamp schematic electronic circuit project is designed using the OP37 operational amplifier manufactured by Analog Devices and is effective, fixed-gain transformerless microphone preamp which amplifies differential signals from low impedance microphones by 50 dB, and has an input impedance of 2 k. Because of the high working gain
Automatic Gain Control Microphone PreAmp
This microphone preamplifier incorporates automatic gain control, which keeps the output level fairly constant over a wide range of input..
Low Noise Microphone Preamplifier Circuit
The microphone preamplifier circuit design presented in this schematic use SSM2015 produced by Precision Monolithics Inc. (PMI) which offers a high amplification and low noise ( 1. 3nV/ f). Has been designed to work with differential input signals and can deliver 10 to 2000x amplification and it is term of R4 value. For R5 = R6 the amplification
Classroom Microphone System Circuit
This audio amplifier circuit is useful in classrooms to reduce the strain of lecturing, if the surrounding environment is noisy. It uses the power amplifier IC LM380 that gives 2 watts output which is sufficient in a confined area. The amplifier is portable and the whole circuit and the battery can be enclosed in the Speaker box itself. The circui
Wireless FM Microphone Circuit
This simple FM wireless microphone transmitter can transmit speech over a short range. It can be used as a simple cordless microphone. The circuit uses two..
Low Voltage Microphone Preamplifier Circuit
This is a low voltage microphone preamplifier circuit with a 1. 5V power supply. The reference, with a 500 kHz unity-gain bandwidth, is used as a preamplifier with a gain of 100. Its output is fed through a gain-control potentiometer to the op amp, which is connected for a gain of 10. The combination gives a 60 dB gain with a 10 kHz bandwidth, unlo
Balanced Low Noise Microphone Preamp
This simple design has very low noise, close to the theoretical minimum, high hum rejection and variable gain with a single rotary pot. It is similar to that used in many professional grade mixing desks and can form the basis of a no compromise recording mixer for live work. The design consists of differential compound pairs of transistors with a
Sound Blaster Microphone Preamplifier
Circuit is based basically on quite well tested my simple microphone preamplifier. I have built one prototype of this circuit and it worked nicely. 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 pac
Microphone Amplifier / Modulator for 7 MHz SSB Transceiver
Microphone amplifier consists of LM324 and two transistors. LM324 is available in 14 pin DIP. I brought it for Rs: 6/-. It contains four identical operational amplifiers. Transistors BC548 and BC558 are used as compressor. I used 2-wire shield wire for connecting microphone. One wire is used for condenser microphone and the other for PTT switch....
Microphone Preamp Buffer Help
Hi I have decided to build this mic preamp and tone control circuit which was posted on a another site. The Eq section is the same one used in the..
Speaker Microphone Circuit
This circuits allows you to use a cheap loudspeaker as a microphone. Sound waves reaching the speaker cone cause fluctuations in the voice coil. The voice coil moving in the speakers magnetic field will produce a small electrical signal. The circuit is designed to be used with an operating voltage between 6 and 12 volts dc. The first transistor op
Sound card microphone
Most sound card microphone inputs require a minimum signal level of at least 10 millivolts, but some older 8-bit cards need as much as 100 millivolts. The typical impedance of the PC soundcard microphone input is in order of 1 to 20 kohms (can vary from card to card). The microphone type which works best with computer sound cards is the electret...
Wireless microphone schematic
This wireless FM microphone is simple to build and it has a useful transmitting range (over 300 meters in the open air). Despite its small component count and a 3V operating voltage it will easily penetrate over three floors of an apartment building. It may be tuned anywhere in the FM band (87-108MHz) and its transmissions can be picked up on any
Simple Microphone Preamplifier Project
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 mic preamp can take both dynamic and Electret microphone inputs (preamplifier provides power foe Electret microphone elem
3 channel microphone mixer circuit with IC741
Low noise microphone amplifier circuit
This low noise microphone amplifier is build with MAT02 produced by PMI. This mic amplifier is very performant and has a verylow noise level. The amplification can be 20dB or 23. 5dB (10x or 15x ) selected by S1. We aim to transmit more information by carrying articles. Please send us an E-mail to wanghuali@hqew. net within 15 days if we are...
Low voltage microphone preamplifier
OP27 Fixed Gain Transformerless Microphone Preamplifier
A simple but effective fixed gain transformerless microphonepreamplifier circuit diagramin the picure below. The circuit amplifies differential signals from low impedance microphones by 50 dB and has an input impedance of 2 kOhms. The OP27/37 operational amplifierhelps to preserve bandwith because of the high working gain of the circui
simple microphone circuit
I want to make a simple circuit with a microphone that just takes your voice and sends it to a speaker. I just want to understand how to hook up a mic..
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...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity