Connect with us

Check if schematic is correct

Discussion in 'General Electronics Discussion' started by Mike555, Apr 24, 2016.

Scroll to continue with content
  1. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    I have a circuit i tried to make a schematic of but i'm not quite sure i got it right.
    If someone would be kind enough to check if i got it right, i'd really appreciate it.
    Here is pictures of the circuit and the schematic i made: http://imgur.com/a/Bi8DT

    Thanks
     
  2. ramussons

    ramussons

    374
    71
    Jun 10, 2014
    Unless we know what is it that you are attempting to do, it will be difficult to give an answer.

    Please give some details....
     
  3. Alec_t

    Alec_t

    2,909
    791
    Jul 7, 2015
    It is preferable to post your images on this site, using the 'Upload a file' button.
    Which IC are you using?
    The LED should have a series current-limiting resistor.
     
  4. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    I'm trying to turn the circuit i have into a schematic so i could better understand how it works.
    I have uploaded the datasheet for the IC below.
     

    Attached Files:

  5. dorke

    dorke

    2,342
    665
    Jun 20, 2015
    This is how I see this.
    There is a need to measure the switch contacts when it is pressed,can you do that?

    z3p0bRv.png
     
  6. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    I tried to measure the switch but pressing it and releasing it doesnt seem to have any effect on the contacts.
    I believe the switch might be broken since it doesnt even turn on the transmitter device.
     
  7. dorke

    dorke

    2,342
    665
    Jun 20, 2015
    Did it work before?
    If so you can use a short-wire to bypass the switch.
     
  8. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    I shorted those contacts i marked with red in the picture below and the LED turns on.
    I'm not sure if those are the correct contacts to short but i assume it is since the LED turns on.
    I also noticed that the IC heats up pretty fast when the LED is on but i dont think thats a problem since the button is pressed only shortly when the device is in use.
     

    Attached Files:

  9. dorke

    dorke

    2,342
    665
    Jun 20, 2015
    Is the device actually working with a receiver?
    Please measure resistance between the 2 yellow circles when the button isn't pressed(no battery).

    P4240001_Short.jpg
     
    Last edited: Apr 24, 2016
  10. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    I measured the resistance between the points you marked while having the battery out and not pressing the button,
    result was out of range. Even if i press the button the result doesnt change.
     
  11. dorke

    dorke

    2,342
    665
    Jun 20, 2015
    Please measure the voltages at the points marked,with the short as you did before.
    Make the short permanent ,then insert the battery for a short period of time (to prevent damage) and measure.
    iK6i6s2.jpg
     
  12. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    The voltage across those points on the modulator is 9.25V when the power is on and 0.80V when the power is off.
    Voltage on the marked IC pins is 11.48V when power on
     
    Last edited: Apr 24, 2016
  13. dorke

    dorke

    2,342
    665
    Jun 20, 2015
    Looks fine the LED is dropping about 2.25V,must be a green led ...;)

    If it works with the receiver,
    you need to replace the defective push button.
     
  14. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    The LED is actually red. I dont know if it changes anything but the input voltage i use is 12.22V and not exactly 12V like it says on the board. I have to test this together with the receiver as soon as i find batteries for it.
     
  15. ramussons

    ramussons

    374
    71
    Jun 10, 2014
    Would someone be kind enough to tell me just what is this circuit? :D
     
  16. Mike555

    Mike555

    21
    1
    Mar 20, 2013
    This circuit is the transmitter of a wireless doorbell.
     
  17. ramussons

    ramussons

    374
    71
    Jun 10, 2014
    Ok. Tks. :)
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-