Wednesday, August 31, 2011

Accurate LC inductance /Capacitance Meter

About The Project 

This is accurate home made LC inductance/capacitance meter built with very common components which are very easy to find all around . The range of this LC Meter is extremely good at measuring very low value of capacitance and inductance.

LC Meter's Inductance Measurement Ranges:
- 10nH - 1000nH
- 1uH - 1000uH
- 1mH - 100mH

LC Meter's Capacitance Measurement Ranges:
- 0.1pF - 1000pF
- 1nF - 900nF


it auto calibrate when power up , so there is no chances of human error in calibration. we can also re calibrate at any instance of time by pressing the reset button.this meter is completely auto range.

Components.

  • No particularly accurate components are required, except for one (or more) accurately known "external" capacitors used to calibrate the meter.
  • The two 1000pF capacitors should be fairly good quality. Polystyrene are preferred. MKT are fine. Greencaps tend to drift in value too much. Avoid ceramic capacitors. Some of these can have high losses (and it is hard to tell).
  • The two 10uF capacitors in the oscillator should be tantalum (for low series resistance/inductance).
  • The 4MHz crystal should be a genuine 4.000MHz one, not something approximate to 4MHz. Every 1% error in crystal frequency adds 2% error to the indicated inductance value.
  • The relay should be a low current one. The PIC can only provide about 30mA of drive current.
  • Don't forget the "catch" diode across the relay coil!




PCB Design








Download the Firmware and schematic





30 comments:

  1. j1 and other jumper j2,j3,j4 grounded same as j1

    used for calibration and debugging

    ReplyDelete
  2. Thancs for sharing.
    This is a very nice project.

    ReplyDelete
  3. i have try this circuit relay was getting on but .. i had a out put is "000000001" . if i disconnect the J1 means "over Range" .. please replay

    ReplyDelete
  4. when you connect the jumper if it show 000000 it means l c oscillator is not oscillating due to some connection fault ,,wrong value or faulty components


    The "Overrange" message is displayed when the oscillator frequency exceeds 655350Hz or falls
    below 2560Hz.

    and the value you saw is telling 00 hz

    ReplyDelete
  5. Hi, Can you plz post source code or send to my mail id swami.gangatharan@gmail.com. Thanks in advance. I tried your serial lcd. It is very useful Thanks for that too......:)... your tutorials are very useful

    ReplyDelete
  6. Hi to all,
    in my case display shows only CALIBRATING and nothing else. What is wrong with my setup? Best regards and many thanks in advance for your kind cooperation
    Ivan

    ReplyDelete
    Replies
    1. if your prototype stuck on calibrating then please check the firmware

      Delete
    2. mine is stuck at calibrating too , what to do now?
      kindly explain jumpers j2,j3,j4 connection?

      Delete
  7. hi my friends...
    I'm from Türkiye.... my name is omer and I need this project a lot....

    but ı couldn't download it.... Who can help me to download......

    And is this project run?
    İf you can know about this project, can you help me...
    Thanks a lot...
    Please contact me with my e-mail.... : e.tronik@hotmail.com

    ReplyDelete
    Replies
    1. i have checked the download like and it's fine please try again

      Delete
  8. Hi,

    have you made any circuit that tell me the voltage rating of a capacitor. i have doubt on voltage rating written on a capacitor.

    ReplyDelete
  9. Do you happen to have the source code available? I'd like to see if I can try to adapt it for a PIC16F88, and possibly 7 segment displays... Thanks.

    ReplyDelete
  10. Hi,
    Can you pls give me the original pcb file?, coz i really dont have very much knowledge abt pcb drawing.

    ReplyDelete
  11. Hello Gaurav,

    Post the source code for this please so we can modify/port.

    Thanks

    ReplyDelete
  12. can i replace pic16f628 with pic16f84a?

    ReplyDelete
  13. how can i change hex code to c language coding.... and also want to know that how can i make microchip ic burner so that i can burn ic

    ReplyDelete
    Replies
    1. sure you can do this is c no problem what so ever.


      here is the link to my another posts whic shows two different programmer .
      http://www.circuitvalley.com/2011/07/pickit-2-clone-universal-microchip-pic.html

      http://www.circuitvalley.com/2011/05/microchip-pic-serial-port-programmer.html

      Delete
  14. i tried this project and the lcd just give "orange" and and some blocks then after press cal button it gives
    "0.4 L= calibr" what is the problem

    ReplyDelete
  15. please , send me the exact size of PCB in pdf .....:- esnehasish@gmail.com

    ReplyDelete
  16. im building a similar project with pic18F242 can I please have the C source code so i can work on it
    thanks

    ReplyDelete
  17. Thank you for this project, is possible to have the source code, or an explanation on how it works?
    Thank you so much!

    ReplyDelete
  18. I need the program for this project. Only Hex file is given here

    ReplyDelete
  19. I have a problem. " over range " what is problem

    ReplyDelete
  20. Replies
    1. yes it works pretty well , i still have it with me since i made it.

      Delete
  21. Hello,

    Can you give me the original pcb file?
    Thanks.

    ReplyDelete