Help with schematic

Discussion in 'The Projects Forum' started by juicethief, Apr 9, 2011.

  1. juicethief

    Thread Starter New Member

    Apr 8, 2011
    6
    0
    Attached is a schematic of an ultrasonic transducer I found on the internet. I am trying to determine how the transistor and feedback loop work. The print is incomplete as transistor p/n does not cross to a transistor and the transformer lacks pertinent details (i.e. secondary voltage or turns ratio). Any ideas?
     
  2. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,741
    759
    Welcome.

    You can forget abt the details, I can hardly read any thing from tht image
     
  3. BillO

    Well-Known Member

    Nov 24, 2008
    985
    136
    The transformer serves two purposes. 1) It steps up the voltage to drive the transducers and 2) Provides a phase shift through the feed-back winding to sustain the oscillation.
     
  4. Wendy

    Moderator

    Mar 24, 2008
    20,764
    2,535
    I believe this is an ultrasonic cleaner, as there are controls for a count down timer and temperature. This means the U/S is going to be fairly powerful.
     
  5. juicethief

    Thread Starter New Member

    Apr 8, 2011
    6
    0
    So here is a (somewhat) better one, I hope. I was mainly curious about what is going in with the R//C & L loop that provides feedback to the transistor. I also curious as to what transistor might work well with this application. Hopefully, with that information I can simulate this in Multisim and get a solid understanding before I waste any efforts constructing.

    Thanks for all the replies thus far.
     
  6. juicethief

    Thread Starter New Member

    Apr 8, 2011
    6
    0
    Apparently bmp's are huge...
     
  7. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Load the .bmp in MS Paint, and then save it as a .PNG file.
    It will be much more compact, and it will not be "lossy" like .jpg files.
     
  8. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    5,675
    899
  9. juicethief

    Thread Starter New Member

    Apr 8, 2011
    6
    0
    could you elaborate on the "Provides a phase shift through the feed-back winding to sustain the oscillation." ?
     
Loading...