Bluetooth range

There are three types of classes in different Bluetooth specification.

Class 1 - Range of fewer than 10 meters
Class 2 - Range of 10 meters (33 feet)
Class 3 - Range of 100 meters (328 feet)

Facts :
  • The range depends on atmospheric, geographic, urban conditions.
  • The range not only depends on the transmitter but also on the mobile phone which is receiving files.
  • The bigger the range, the slower transmission speed.
  • Here above Bluetooth range described above. There are three types of classes. class 1 devices transmit at 1 mW with the range of fewer than 10 meters. Class 2 devices transmit at 2.5 mW with a range of 10 meters or 33 feet. Class 3 devices transmit at 100 mW with the range of 100 meters or 328 feet.

Difference between active transducer and passive transducer

The transducer which generates the output in the form of voltage or current, without any external energy source is known as an active transducer, while in passive transducer means that the like capacitance, resistance, and inductance changes because of the input signal. Here this post we understand the difference between an active transducer and passive transducer

The main key difference between an active transducer and a passive transducer given below:
  • The transducer which gives the electrical output without any external source known as the active transducer while in physical transducer whose physical properties varies because of the input or measured signal known as the passive transducer.
  • The active transducer is also called a self-generating type transducer while the passive transducer is also called an externally powered transducer.
  • The active transducer does not require any additional source while the passive transducer requires the additional energy source.
  • Active transducer does not require any auxiliary power supply, Passive transducer require an auxiliary power supply for transduction.
  • The active transducer, the signal conversion is simpler, while in passive transducer the signal conversion is more complicated.
  • Active transducer the energy to produce output obtained from the physical quantity, while in passive transducer they also derived part of the power required the conversion from physical quantity under measurement.
  • The latest example of the active transducer is bourdon tube, Passive transducer is LVDT.
  • It generated electric current or voltage directly in response to environmental stimulation, while in passive transducer gives a change in some passive electrical quantity, such as capacitance, resistance or inductance as a result of the stimulation.
  • The design of the active transducer is simple as compared to the passive transducer.
  • The resolution of the active transducer is low while that of a passive transducer is high.
  • Active transducer draws energy from the measured source and gives the electrical output while in passive transducer the transduction can be done by changing the physical of the material.

Transistor advantages and disadvantages

Basically, the transistor is nothing bur solid-state equivalent of a triode valve which was used in radio and early computers. It is made of three-layer semiconductor materials. Common semiconductor two materials in transistor construction are silicon and germanium. It basically acts as an insulator and a conductor. This page almost covers the advantages and disadvantages of the transistor to better understand this topic. 

Advantages of transistor:
  • It is used for fast switching applications
  • Smaller mechanical sensitivity
  • It is used as a current controlled current gain
  • It is available at very low cost
  • It is very smaller in size
  • Fast switching
  • It has a longer lifeLow operating voltage for greater safety, lower costs and  tighter clearances
  • Extremely long life
  • The transistor is very easy to turn ON and turn OFF the power transistor
  • The power transistor can carry large currents in ON state and it blocks very high voltage in OFF state mode
  • ON state voltage drops across power transistor is  very low
  • The power transistor can be operated at switching frequencies in the range of around 10 to 15 KHz
  • There is no power consumption by the cathode heater
  • It uses low voltage for its operation hence it offers more safety
  • It can be used to control the power delivered to the load in inverters and choppers
Disadvantages of transistor:
  • It has reverse blocking capacity is very low
  • It can be damaged due to the thermal runaway or second breakdown
  • Manufacturing techniques are very complex and require a clean room environment
  • Due to its small size, it is difficult to trace out faulty ones due to failure. Moreover, it is very difficult to unsolder and replace new ones
  • Power transistor cannot be operating satisfactorily above switching frequency of  around 15 KHz

Advantages and disadvantages of manometer

The manometer is measured an unknown pressure by balancing in against gravitational force of liquid heads. It can be used to measure dynamic pressures and differential pressures. It can be measure pressure ranging from low to high. Here this page covers the advantages and disadvantages of the manometer  to better understand this topic. 

Advantages of  manometer:
  • It has a low cost
  • The manometer is suitable for low-pressure applications
  • It is simple in construction
  • It has better sensitivity
  • It has good accuracy
  • It has simple operation and construction
  • It does not have to be calibrated against any standard, the pressure difference can be calculated from the first principles
  • The manometer is available for a large range of filling fluids of varying specific gravity
Disadvantages of manometer:
  • It is large in size and bulky
  • It needs leveling
  • No fixed reference is available
  • In manometer, the error is introduced due to condensation
  • It has no over range protection
  • The manometer has a poor dynamic response
  • They have a smaller operating range which is on the order 1000 KN/meter.meter
  • They are fragile and hence offer less portability
  • The manometric fluids density depends on temperature. Hence errors may result due to change in the temperature
  • It has a slow response which makes it unsuitable for measuring fluctuating pressures  

Difference between PCM and DPCM

We have to learn about this topic first let we understand the full form of PCM and DPCM. PCM and DPCM are the methods of the procedures used for transformation analog signal into a digital signal. These methods are different as the PCM method are represents sample value by code words whereas in DPCM the original and sample values depend on the previous samples. Here this post gives information about the main comparison between PCM and DPCM to better understand this topic.

The main key difference between PCM and DPCM are given below:
  • PCM stands for pulse code modulation, DPCM stands for differential pulse code modulation.
  • PCM can be required highest bandwidth but  DPCM required small bandwidth. 
  • PCM is comprised of complex notation as to when DPCM has simple notation.
  • PCM  can be used 4,8,16 bit per sample, DPCM can be uses 2 or 3 bit per sample.
  • In PCM the quantization error depends on a number of levels, While in DPCM slop overload distortion and quantization noise is present.
  • PCM has a better signal to noise ration while DPCM has an average signal to noise ratio.
  • In PCM the number level depends on the number of bits, While in DPCM has fixed number of levels are used.
  • Both PCM and DPCM techniques suffer quantization error and distortion but different extent.
  • PCM has no feedback in transmitter or receiver, but in DPCM feedback is present.
  •  PCM is used in audio, video, and telephony, while in DPCM is used in speech and video application.
  • If we talk about efficiency DPCM is a step ahead of PCM method.
We conclude that the above difference is that PCM procedure sample and convert analog waveform into a digital waveform directly with the help of an analog to digital more covert. On the other hand, DPCM does similar work but uses multibit difference value.



Difference between time domain and frequency domain

We all know that, the time domain is the domain in which all the signals are to be represented. Time domain signal can be tested or verified with the use of an oscilloscope while in the frequency domain is useful to do a deeper analysis of the time domain signal. Frequency domain helps to study contents of the discrete time domain signals as well as continuous time domain signal.  While in frequency domain signal can be analyzed with the use of spectrum analyzer. Here this page gives information about the difference between time domain to better understand this topic.

The main key difference between time domain and frequency domain are listed below:
  • A time domain graph shows how a signal changes over time while the frequency domain graph shows how much of the signal lies within each given frequency band over a range of frequencies.
  • The main advantages of time domain are that they are relatively fast and require less memory than inverting the Helmholtz operator, While in frequency domain main advantages are that the frequency domain allows for techniques which could be used to determine the main of stability of the system.
  • Time domina is the domain for analysis of the mathematical function or signals with respect to time, Whereas the frequency domain is the domain for analysis of the mathematical function or signals with respect to frequency.
  • The time domain systems tend to use photon counting detectors which are slow but too much highly sensitive, while frequency domain system is relatively inexpensive, easy to develop and use and can provide a very fast temporal sampling. 


Advantages and disadvantages of atm

First, let us understand what is the full form of ATM. To operate the ATM card, the customer has to insert the card in the machine. He has to enter the password number. The authentication or password number is correct, The ATM  permits a customer to make entries for withdrawals or for the deposits on completion of the transaction, the customer's card is ejected from the ATM. This post gives information about the advantages and disadvantages of ATM to better understand this topic.

Advantages of ATM:
  • Withdrawing money
  • Round the clock services: ATM provides banking services to its customers round the clock 24 hours a day, 7 days a week and 365 days a year
  • ATM device can check how much money is remaining in the account
  • It is possible to withdraw from many regional and global banks. ATMs are a method of the deal because they are internationally acknowledged
  • Checking recent or past bank statements
  • Nowadays almost every shopping mall, restaurant, and other organizations are accepting debit or credit card payments
  • ATM machine will provide expansion of services to any corner of the world
  • It may also be used in foreign countries
  • It reduces the hustle and bustle required when performing a transaction via a teller. Since there is no usage of slides in ATMs there is no stressful filling of forms
  • ATMs very beneficial for travelers
  • ATMs provide privacy in banking transactions
  • No more filling out a deposit slip as well as withdrawal slip
  • ATM  is  to much faster less hassle
  • ATM card is protected by a PIN keeping our money is totally safe
  • Can monitor or track the account
  • Can withdraw anytime, day or night at any locations as long as the ATM card is also linked in the other bank, so its good for people
  • ATMs reduce the work pressure on bank staff and avoid queues in bank premises
  • Access to bank from any part of the world called as an essential banking service like deposits, withdrawals, transfer of funds, etc can be accessed by customers from any part of the world
Disadvantages of ATM:
  • The machine may not recognize your credit card
  • Maybe no ATMs nearby
  • If someone watches or hacks an ATM machine your details may be taken, so lots of hugs will be created
  • If the problem with a credit card you can not withdraw your money
  • If someone watches or hacks ATM machine details may be taken if you forget your PIN number you cannot use the card
  • Cannot be provided in rural areas like in our country like India where banks are having a large number of rural and noncomputerized branches ATM services cannot be provided
  • Limitation of cash withdrawals
  • The cash deposit facility is restricted and not safe as the dropping of envelope and ATM  is not advisable
  • Possibility of missing ATM card
  • Loos of personal touch with the banks
  • The risk to robbery when withdrawing a money
  • Some charges of other banks are expensive
  • ATM has run out of cash