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28 Threads found on Sound Detector
The LM3914 is a linear voltmeter but the LM3915 is better for measuring the logarithmic relationship of loudness with our hearing. My circuit uses a peak detector and its LEDs do not flicker, they show the exact levels of sounds. With no sound all my LEDs are off. With loud sounds all my LEDs are on at the same brightness. (...)
the harmonics at that angle , makes the core vibrarion and produce a humming sound.
Piezo beepers may serve as microphones for your drums. They can bear up when exposed to sound which is high impact and high volume. I did experiments with tapping an inexpensive piezo unit. It gives an output as high as 1/10 VAC. So if you bias a transistor just to the right point, it will turn on in response to the additional voltage from a piezo
I can't help but I would urge caution when using ultrasonics between object moving at high speed in turbulent air. Even doppler shift could stop it working but I would imagine the sound pressure waves would be severely distorted by the air flow. Consider a vehicle travelling at say 100Kph against an air stream of 20Kph, the chances are the sound r
The datasheet of the LM3915 bar graph IC shows a few excellent peak detector circuits. The opamps need a dual polarity supply. In my sound Level Indicator project I used an opamp that works with its inputs at 0V so it does not need a negative supply. It is inverting so when its input is negative then its output goes positive. A transistor emitte
This is ustrasonic range finder. Transducer is transmitter and receiver for echo sound. First two OPAs are AC amplifiers and antiparallel diodes at the second OPA negative feedback serve for signal amplitude limiting both positive and negative. Third diode from the output of second OPA is envelope detector whose signal is inverted in third OPA and
Hi friends I saw some article about building metal detector with cd, dvd, calculator and headphone!! i made it but i didn't hear any sound, anybody have some experience with this kind of metal detectors? can this detectors work?!!! i don't think so!!! Regards
sound like this may be need DLL file , collect template to protocal for communication . Library is required from mobile producer , I think it's hard to decise to corperate company. So u may use the sms chip, 2 chips form the communication system, that easy way right.
Hai Can you help me to write a php script for receiving the http query "s=Silence!(since%date%time) " .This query is actually send by a software named "silence detector" for detecting silence in the sound card input.When it detect silence it send a http query to the server. Then server receiving the query same time it record and display t
The spec of the electret mic element should show you what kind of signal you will get out of it. You'll need an amplifier (a single transistor amplifier will be sufficient, no need to use an IC). BTW, you don't really need a microcontroller to light an LED when there is sound. I just googled for "sound detector circuit" and there were plenty (...)
please read your datasheet, there it says: Working: Power up the sensor by 5VDC using pins ?VCC? and ?GND?. First of all a 10us trigger input has to be given to the pin named ?Trig? on the sensor. This starts one cycle of range conversion and sends 8 bursts of sound waves from the transmitter. As soon as the signals are
Yes it's possible to design such a circuit Eg sound Activated relay Switch ,so that when the detector sounds it will activate the relay switch sound Activated Relay Switch Post added at 20:00 ---------- Previous post was at 19:39 -------
Maybe you find some idea here............ Download sound Frequency detector Software: Audio detector, Metal detector Treasure Hunter Pro, Note detector, ... True oscilloscope, spectrum analyzer, frequency meter, voltmeter, function generator and distorsiometer for
need to measure the sound Pressure from 30 to 110 db and display on LCD using PIC 16F877. on the internet i found using LM358 (pre amp + peak detector) and CA3140 (no high gain, mean preamp) for single supply and TL071 (pre amp) with LF351 (half wave rectifier) with Dual supply. any idea how to show db values using these circuits and will
Hi, It depends on the zero cross detector circuit. Of course, you need to write code to detect zero cross, but the amount of code to be written depends on the detector circuit being used. Have you decided which circuit to use? eg. You could use something like this: or something from [UR
What type of sound sensor you are using?
Use a transformer that after rectification and smoothing gives around 24V dc and here is an example of a circuit that will produce zero-crossing pulses .. IanP :D
Designing a ultrasonic receiver consisting of JK flip-flop 74hc107, LM311 and a peak detector using tl071. When sound is detected the buzzer will activate. But how do I connect the comparator lm311 to JK flip-flop? Because at the moment the buzzer is always ringing on Q bar output 74hc107. Updated posted: file attached
Curiously, D3 has no function in the said circuit, because it's permanently reverse biased. If you put a capacitor in series with R13, it would have a purpose. As a general remark, it's a very simple proximity detector, because it only measures intensity rather than transit time of ultrasonic sound.
I answered you in a PM and on two other electronic chat forums. The LM358 will work but it is old and will reduce the sensitivity to sounds above 5kHz. the MC33172 responds well up to 26kHz in my circuit. Newark has them. Farnell is worldwide in 32 countries and now owns Newark. My prototype has been blinking for over 3 years and still works
You can find a number of site for Zero Crossing detector, Applications Notes of Op-Amps etc, I am giving you only one (but good one) site . i.e. Zero Crossing detector
Use zero-crossing detector circuit and you will have 100 pulses per second .. Here are examples: Regards, IanP
First of all, I must admit that my knowledge on opamp is very limited. Would someone pls advise what are the functions of IC1A and IC1B in the circuit? How do we relate the sound -> microphone ->
hi all plz can any one help me with my project (decible meter/sound meter)or (sound detector) thanx
One simple way is to have a necklace on the cat with pulsed LEDs . Then in each room there are optical sensors. Their outputs are amplified through band pass amplifiers tuned to the pulse frequency. The alternatives of sound generators on the cat would irritate it. Radio methods are more complex because the receivers can detect through wall
I want to design a input circuit for my sound Level Meter with LM3915. this is my first project with an audio signal. LM3915 is bassicly a display driver. the aim of this project is to display the signal received form microphone to sound level meter. example, let say the Mic receive a noise from sorrounding area(people talk), then the (...)
If the quoted statement is true you would not be able to hear any soud from speaker. And it is not the average value of the signal that produces sound but it's rms value.
Here is my proram DTMF detetor using sound card, the audio sinal input is mic_in or line_in, enjoy :roll: