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    IR Circuit question

    I'm trying to make a simple IR circuit that energizes a coil when the detector "sees" the beam (refer to attached schematic). The problem is when the everything is active, I have almost no current at the coil. Why am I losing so much current? I suspect it's because the base of the NPN transistor...
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    Magnetic Pendulum

    I'm trying to make a magnetic pendulum circuit for a holiday decoration, and I need some help. I found this circuit online (see attached JPG), but the circuit behavior is not consistent and it rarely works correctly. Most of the time, the coil is ALWAYS on (rather than momentarily on when the...
  3. 1

    TO-247 bent pins

    Long-short question: I am working at a new project, a lab power supply. I used some TIP3055 for this project. Those TIP3055 were recovered from another project and the pins were a little bit short. I was forced to bend them from near the plastic case to make them fit to the new project PCB...

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