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Unable to send current through high frequency transformer

  1. Mar 10, 2013 #1
    I am building a transformer of about 9.3 gain operating at 20kHz. One would think this is saturation but if that were the case there would at least be some voltage across the load. The gain of the transformer is as expected for no load conditions but I cannot get this same voltage across a load. What could be the cause of this?
  2. jcsd
  3. Mar 10, 2013 #2
    Is the 9.3 voltage gain or current gain? What is the impedance of your load? How many turns do you have for your primary and secondary and what type of core are you using?

    Do you have any ideas what the problem might be?
  4. Mar 10, 2013 #3
    the 9.3 is current gain. There is no voltage across the load which is a 1k resistive load. I think it has to do with the manner in which I have wound the secondary. What is the proper method of doing this? This isn't saturation.
  5. Mar 10, 2013 #4
    For a current gain of 9.3 the primary should have 9.3 more turns than the secondary. What happens to the signal generator output when you put a 1K resistor across it?
  6. Mar 11, 2013 #5


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    I don't understand your notation clearly. Are you saying that there is a 9.3:1 turns ratio or a 1:9.3 ratio? What is the measured voltage ratio?
    What is the core made of and what shape is it? Do you have a picture. The reason I ask is that the fault seems so bizarre that there must be something drastically wrong.
  7. Mar 11, 2013 #6
    Correction to post #4: I left out the word times and in "For a current gain of 9.3 the primary should have 9.3 times more turns than the secondary."
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