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Question about oscillator circuit

  1. Jun 30, 2012 #1
    I'm new to electronics and I just bought an electronics project kit and built a pulse tone oscillator (the schematic is attached). The manual doesn't go into very much detail about how the circuit works. I've built a few simple circuits before in physics 2 and I understand how the individual components of the circuit work (transistors, capacitors, etc).I understand how speakers work and I have a built a simple oscillator before with just a capacitor and inductor but I'm having trouble following exactly what is going on. Could someone please give me a detailed explanation of exactly what is happening in this circuit? All the manual says is that the .047 uF cap is rapidly charged and discharged and that the feedback control circuit is key. Here is what I think I know: current flows from emitter to base turning the transistor on and allowing current to flow from emitter to collector and to ground. the .1uF capacitor is charged from the current coming from the collector but I think it would be immediately disharged? The .047uF capacitor is tapped in to the base of the transistor and is charged from the current flowing from emitter to base...That' s about all I have. I also don't understand why the output transformer has two terminals plugged into the positive side of the battery. Is there two individual coils? Is the alternating current provided by the oscillator going through both? Any help would be greatly greatly appreciated. This is driving me crazy

    Attached Files:

  2. jcsd
  3. Jun 30, 2012 #2
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