What are Sound Transducers
Hello friends, I hope you all are doing great. In today’s tutorial, we will discuss
What are Sound Transducers. The transducer is a module used for the transformation of energy from one type to other types of energy. For instance, the loudspeaker converts the electrical signal into the sound. Transducers are mostly used in automation (It is a technology that used for a different process where most work is done with less manpower), measuring devices, and for the conversion of the electrical energy into the different physical parameters like force, sound, light, etc.
In today's we will have a look at sound transducer's working, construction, applications and other related terms. So let's get started with
What is Sound Transducers.
What are Sound Transducers
- The sound transducer is an instrument that used for the transformation of the sound into the electrical signal and electrical signal into the sound.
- The acoustic waves are defined as the sound that we hear. The frequency range of the sound is from one hertz to several hundred hertz, but the range for the sound that we can hear is twenty to twenty thousand hertz.
- There are the 2 main categories of the sound transducers first one is input transducers and the second one is output transducers.
- Input transducers are that converts sound energy into the electrical energy, an example of these transducers is a microphone that converts our sound into an electrical signal and sends to the loudspeaker.
- The output transducers are that changes the electrical signal into the sound wave, its example is loudspeaker that converts the electrical signal into the sound received by the microphone.
- These transducers have the ability to transform less and higher frequency sound waves lesser frequency waves are known as infrasound wave and larger frequency sound waves are recognised as the ultrasound.
What is Sound
- Sound is the type of energy generated by the vibration produced by beating drum, vibrating tuning fork and the vibration's energy depends on the source that producing these vibrations.
- The frequency of the sound oscillations produced by the drum is less while sound producing from the cymbal (it is a musical device) has larger frequency.
- Like an electrical signal, the sound wave also has velocity, frequency and wavelength.
- The wavelength (?), frequency (f) of the sound rely on the source that produced the waves. But the velocity of the sound depends on the propagation matters like solid, liquid, or gases.
- The mathematical relationship among the frequency, velocity and wavelength is written here.
V= ƒ?
- The wavelength (?) can be defined as the time required for completion of the one sine waveform.
- Frequency (f) is the no of sine waveform in one second, its unit is hertz.
- Velocity (v) is the distance covered by the wave in one second, its unit is m/s-1
Input Sound Transducer
- The microphone is defined as the input sound transducer because it converts the electrical energy into the sound.
- There are various categories of the mic according to the electric transducers that are working with it.
- Mic also consists of the sound filters circuitries and repeaters circuits that maintain the signal strength after some time.
- The features of the mic are electric and acoustics. The sensitivity of the mice can be defined as the millivolts of the electrical signal produced by the per-unit intensity of the acoustic waves.
- The impedance value of the mic defined the value of the electrical signal at the output if the impedance is larger than the output will also large, impedance is less output will also less.
- Now we discuss the carbon microphone and its working.
Carbon Microphone
- The mic was invented in the world that used in old fashion telephones for conversation is was carbon mic.
- Nowadays these mics have been substituted with the electret mics.
- Carbon mics consist of the piece of the carbon among the diaphragm and back-plate.
- When the pressure is an external sound signal is applied to the carbon piece, then the value of the resistance decreases.
- The sound waves collided with diaphragm cause to decrease the resistance of the carbon piece.
- The output delivered by the carbon mic is according to the sound standard.
- The given below diagram explains the structure of the carbon mic.
Output Sound Transducer
- The use of mic is useless if it is not connected with the output for the conversion of the electrical signal into the sound wave.
- The examples of the output transducers are speaker, bells, that converts an electrical signal into the sound.
- Ear-phones are one of the best output transducers that have used earlier than the mic.
- In previous years the ear-phones were used with Morse key (it is an electrically operated switch used in telegraph) in the transmission of the signal through telegraph.
- With the discovery of the mic, there were several models of the input and transducers were invented like the telephone.
- Speakers are exits in different physical structure, frequency limits and area. The transducers are also known as pressure modules because they convert an electrical signal into the pressure of the air.
- For high pressure, the speaker comprises a motor that converts an electric signal into the sound waves and diaphragm that pushes adequate air to make the vibrating effect hearable.
- In given below diagram the speaker internal structure is shown.
Now we discuss the practical applications of the sound transducers.
Applications of the Sound Transducers
- These are some important applications of the sound transducers that are described here, with detailed.
- Sound transducers are used in the telecommunications almost all telephone and mobiles consists of these transducers.
- Television and LCDs also consist of the sound transducers.
- Computer, laptops, radio also uses these transducers for the sound.
- In a conference or larger conventions hall, these are used for the propagation of the sound to the people.
It is the detailed article on the sound transducers if you have any question ask in comments thanks for reading. Take care until the next tutorial.
What are Temperature Sensors
Hello friends, I hope you all are doing great. In today’s tutorial, we will have a look at
What are Temperature Sensors and their implementation in different engineering projects
. The most significant parameter in industries and different engineering project is the temperature that determines the working conditions of the surroundings or instruments. The correct value of the temperature is essential for the implementation of the different accessories and components in engineering projects, circuits, in medical labs, different research laboratories. To measure different values of the temperature different types of sensors are used.
Mostly used temperature sensors are thermistors, thermocouples, infrared radiation detector, and RTD. In today's post, we will have a look at uses, working, construction and different parameters related to temperature sensors. So let's get started with
what are temperature sensors.
What are Temperature Sensors
- The numerous kinds of temperature sensors are available in the market according to their use like a thermistor, resistance temperature detectors, etc.
- Every sensor has a different working principle like RTD measure temperature by variation in the resistance and thermocouple measure temperature by variation voltage at its terminals.
- As the working principle of every sensor is different but the common factor is that all these sensors calculate temperatures by detecting the alteration in the physical parameters of different substances like resistance, pressure and temperature.
- Each sensor after detecting physical parameters variation converts it into the temperature value and shows on the LCD connected with it.
- Temperature sensors are mostly used in high voltage (HV), alternating current (AC) networks, medical instruments, beverage system to maintain the temperature value for the safety of our different products.
- The thermometer is a frequently used temperature sensor, that computes the value of the temperature of fluids, solids substances, and different gaseous materials.
- I have shared a simulation in Labview for Temperature Sensing, which will help in better understanding.
Units of Temperature
Celsius
- Celsius is mostly used temperature unit in the different engineering and industrial temperate measurements.
- It is an experimental scale that was formed by ancient development, that defined its 0 points by comparing it to the freezing point of water and its hundred degrees compared with the point at which water boiled.
Fahrenheit
- This unit is used by metrologists for the measurement of the surface temperature. But mostly used temperature unit is Celsius so it can be easily converted into the Celsius by using this formula.
C = (F-32)/1.8
Kelvin
- This unit of temperature is used for the different scientific temperature measurements. It can also convert into the Celsius by this formula.
k=C +273
Types of Temperature Sensors
- There are numerous categories of temperature sensors according to their working principle, applications and method of temperature measurement.
- We will discuss different and commonly used kinds of temperature sensors some important sensor are listed below. Let's discuss all these senors with the detailed.
- Thermometer
- Thermistor
- Resistor temperature detectors (RTDs)
- Semiconductor
- Infrared Sensors
Thermocouples
- The thermocouple is the abbreviation of TC, it is generally used the sensor for temperature measurements.
- The physical structure of these sensors is very strong, less expensive, there is no need for separate power supply for this sensor, it has an internal battery.
- This module comprises of the 2 different metals that are recognised as open and closed. The working phenomena of the metals of the thermocouple follow the thermoelectric effect.
- For the safety of thermocouple from different environments factors like temperature, moisture, pressure, and gases it is covered with plastic and different ceramic materials sheets.
- The general categories of the thermocouple are K, T, E, S, and B. The J, T, K are generally used thermocouples for temperature computations.
Resistor Temperature Detector
- The temperature's value calculates by the RTD has higher accuracy than other sensors.
- As with the variation of the resistance it measures the temperature, its resistance variation is directly proportional to the temperature values.
- The materials that are used for the construction of this sensor are Pt (platinum), nickel (ni) and copper (Cu).
- It can measure temperature form the minus two seventy celsius to eight fifty celsius.
- In this module, there is no internal power supply it needs external supply for continuous work.
- But the due current power loss occurs at the resistance that can be calculated by this formula.
?T = P x S
- In this equation, the T is temperature P is the power that loss at the resistance.
Thermistors
- A thermistor is a less costly, adjustable and can be used in easiest way. It measures the value of the temperature by the change in the resistance.
- Ther are 2 main types of the thermistors first one is NTC (negative coefficient thermistor) and second is PTC (positive temperature coefficient).
- In the case of the PTC, the temperature and the resistance is directly proportional to one another, with the increase of the temperature there is also an increment in the resistance.
- While in the NTC the temperature and resistance are inversely proportional to each other.
- These sensors are formed by the oxides of the different metals like the manganese (Mn), nickel (ni).
- This sensor is highly sensitive it detects very minute variations in the temperature.
Thermometers
- To measure the temperature of the different matters like fluids, gaseous materials, and solids the thermometer is used.
- The word thermometer is a mixture of the 2 different words first one thermo that means heat and the second one is the meter that means to measure something.
- The thermometer is similar to a tube that is assembled by the glass and consists of the mercury.
- When the temperature rises the mercury in the tube expands according to the temperature and temperature value can be measured from the scaling on the wall of the tube.
- The value of the temperature can be measured in k (kelvin), F (Fahrenheit), centigrade (C) according to the set scale.
Semiconductor Sensors
- These sensors are available in the different integrated circuitries. Due to such type of designs, these are also recognised as the integrated circuit sensing devices.
- There several types of these sensors like diode sensor, digital sensors, etc. The work at among the temperature range from fifty-five to plus one fifty celsius.
- The example of these senors are LM35 and AD590.
DS18B20 Temperature Sensor
- DS18B20 work on the single wire protocol and it used to measure temperature from -55 Celsius to +125 Celsius. It can receive data from nine bit to twelve bits.
- As this sensor uses single wire protocol sensing and receiving data so it can very easily be controlled by the one pin of the microcontroller.
- A single wire is mostly used protocol and every DS18B20 consists of the sixty four-bit serial code that used to regulate more than one components by a single pin of the microcontroller.
- Due to the single wire protocol, the DS18B20 Arduino interfacing is very common to send and receive data and controlling of other senors.
IR (Infrared Radiation) Sensor
- This type of sensor used infrared radiations for the measurements of the temperature.
- There is no need for physical connection for these sensors with the device to that temperature has to find.
- For instance, if someone in the classroom and has an IR sensor than he can easily find the value of the temperature of the chair in the classroom.
- There are 2 main categories of IR sensor first one is the quantum and the second one is thermal.
It is the detailed article on the temperature sensors I have mentioned each and everything related to the sensors and their types. If you have any question ask in comments. Thanks for reading.