CrazyEngineers
  • Basic Electronics: Part 2

    Resistors

    1. Its a electronic or electrical device that resist the flow of elctrons through the device.

    2. They are passive devices that is they have no source of power or amplification but it attenuates the voltage or current signal passing through them.

    3. Because of this attenuation the electrical energy is lost in the form of heat as the resistor resist the flow of electrons .

    4. Most of the resistors are linear devices and obeys ohms law.

    5. They are represented by the zig-zag line. Its unit is Ohm.(Ω)

    [​IMG]

    6. Some important characteristics of resistors: temperature coefficient, voltage coeffcient, noise, frequency response, power, temperature rating, physical size and realibility.

    Applications :

    1. Used in amplifiers as load for active devices, and as feedback elements.

    2. When used along with capacitors, they establish time constant and are used as filters. Helpful in setting operating point and signal levels.

    3. In radio frequency circuiuts, they are used as coils in the form of inductors.

    4. In logic circuits they are use as bus and line terminators. They are also used as pull-up and pull-down resistors.

    Types of resistors

    Based on the mode of operation they are classified into two types

    1. Fixed point

    2. Variable resisters.

    1. Fixed point:

    · They have only one single value of resistor associated with it.

    · They are further divided based on the type of material used for it such as metal wound, wire wound, carbon composition resistors.

    Colour coding in resistors.

    To indicate the value of resistors this type of colour coding is used. This is done because the size of the resistor is so very small to write its value on it.

    There are four bands into it.

    Value of resistors is calculated from left till right.

    Digit, digit, multiplier= colour , colour×10colour(Ω)

    =4,7,103 =47000 Ω

    Thus here, the valure of resistor will be:

    [​IMG]


    [​IMG]

    Clue to remember this colour code:

    Bright (black)

    Boys (brown)

    Rave (red)

    Over (orange)

    Young (yellow)

    Girls (green)

    But (blue)

    Veto (violet)

    Gets (grey)

    wed. (white)


    2. Variable Resistors:

    Here the resistance can be adjusted while it is in connection with the circuit.they usually have three leads, two of them are fixed and one is variable. If contacts are made to only two leads then it is called as a rheostat. If all the three contacts are employed then it is called as potentiometer.
    Replies
Howdy guest!
Dear guest, you must be logged-in to participate on CrazyEngineers. We would love to have you as a member of our community. Consider creating an account or login.
Replies
  • Ankit Litoriya

    MemberJun 17, 2014

    they r jus basics ,,evryone knows here about this , can u come with components like opamp their working transducer and all
    Are you sure? This action cannot be undone.
    Cancel
  • Kaustubh

    MemberJun 17, 2014

    can u post about non linear resistor, its design and applications?

    how can one design a variable electronic load in a simplified manner??
    this was a part of the problem statement for my graduate project...I partly completed it....I would be thankful if i get some suggestions.
    Are you sure? This action cannot be undone.
    Cancel
  • themask

    MemberJun 17, 2014

    Helpful for a newbie to electronics. Keep going ...
    Thanks
    Are you sure? This action cannot be undone.
    Cancel
  • Prajakta Kelapure

    MemberJun 19, 2014

    Ankit Litoriya
    they r jus basics ,,evryone knows here about this , can u come with components like opamp their working transducer and all
    yes ,sure... I am working on it... but thought to start with basics and then with actual electronics components...
    Are you sure? This action cannot be undone.
    Cancel
  • themask

    MemberJun 19, 2014

    Prajakta Kelapure
    yes ,sure... I am working on it... but thought to start with basics and then with actual electronics components...
    Yes you are right, starting with the basis like this will be helpful for a newbie like me.
    Are you sure? This action cannot be undone.
    Cancel
  • Prajakta Kelapure

    MemberJul 1, 2014

    Kaustubh
    can u post about non linear resistor, its design and applications?

    how can one design a variable electronic load in a simplified manner??
    this was a part of the problem statement for my graduate project...I partly completed it....I would be thankful if i get some suggestions.
    #-Link-Snipped-#
    I hope this link may help you .
    Are you sure? This action cannot be undone.
    Cancel
  • themask

    MemberJul 2, 2014

    The images are missing and cannot be seen.
    could you please correct that ?
    Are you sure? This action cannot be undone.
    Cancel
  • Prajakta Kelapure

    MemberJul 2, 2014

    themask
    The images are missing and cannot be seen.
    could you please correct that ?
    hii,
    So only I have attached the file. It consist of images also.
    Are you sure? This action cannot be undone.
    Cancel
  • themask

    MemberJul 2, 2014

    thanks
    Are you sure? This action cannot be undone.
    Cancel
Home Channels Search Login Register