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  1. K

    How to increase reactance in a coil of few turns?

    Remember that the current specified on a fuse is the peak current. You can have a 3amp average transformer and still get higher peaks. The wire amperage chart is the average current. In other words it's different than the fuse. The current for a 22AWG is about 1A average. Could somebody...
  2. K

    Many supply voltages

    I am in the process of a project and I am concerned that I may need many different supply voltages. I want to revamp this circuit I have to include the correct supply voltage. I really want to maximize this circuit and the constraints of a few voltage levels is not acceptable. How difficult is...
  3. K

    Pulse Width Modulation

    Do you think a series transistor would work? Set the current you will need when the voltage is 24V. Bias the transistor with the input voltage. Use a second transistor to reverse the junction. Drive that transistor with PWM clock. You can step down the voltage with resistors to run the PWM...
  4. K

    Winding your own Transformer?

    I tried to build an autotransformer, but it turned out to be a high current inductor. It doesn't quite obey the 20db per decade law. The reason I could not make it an autotransformer is because the reactance wasn't high enough to connect it to the mains. I needed the thing to consume 20A peak...
  5. K

    signal conversion

    A pulse counter will continue to count the pulses indefinitely. Let's say you have a high frequency and the pulses you count are many for a certain duration. So you set the duration with the enable line. You still have a bunch of frequencies that need to be separated so that you have one...
  6. K

    Latch triggering

    I don't think switch bounce is the problem. I can reset it and it still triggers because there is a pulse on the set. Does this sound like switch bounce? I am not really sure what switch bounce amounts to. I know that it is an irregularity in the pulse caused by the bouncing contact which would...
  7. K

    Latch triggering

    I want to be certain that the latch is not in the unknown region when I try to trigger it. Can I skimp on the voltage to keep it from triggering?
  8. K

    C problem

    I am using the Borland compiler and the examples don't seem to work. I make a call to a standard function in the correct header file and it says it doesn't exist. What could the problem be? I have had similar problems with serial communcations functions. I have a theory as to why it does not...
  9. K

    Square wave to Sine wave

    Whatever happened to the sine wave oscillator that used a square wave with an inserted DC level on the transistion. I think it was called a modified sine wave. The article you have listed does not include this tidbit of information. Do you think this is too high tech of a topic.
  10. K

    transistor uses

    Sec has the exact quote that I intended to be illustrated. The emitter impedance has to be low because of the the two base resistors. You can't just choose high value resistors and expect to get the high impedance. The transistor dictates the value of these two resistors. This is why a need a...
  11. K

    Latch triggering

    I have this latch I want to trigger, but it is very sensitive. So I used a pull down resistor on the input. The input to the latch is the ouput of a gate. This seemed to pull down the voltage so that it would not be so sensitive to trigger with a short duration pulse. Do you think this actually...
  12. K

    reliablity of hFE

    I know that a transistor is biased a it's mid current value. From there the power must be decided on and that will determine the voltage. I suppose half power is reasonable. The real test is to determine the beta and the changes in VCE that will keep the beta constant. I would like to tell of an...
  13. K

    Shift Register

    What I am actually looking for is the D flipflop arrangement in integrated form. Is there a more simple integrated circuit. The complexity of these circuits is unwanted.
  14. K

    Shift Register

    Please let me know of a simple shift register with a clock input where the data propagates through the device. The one I bought shifts the first bit to the end and requires a shift out function.
  15. K

    Mains current detection

    You might consider the use of high power resistors, diodes, and capacitors as well as the triac. This way we can avoid the transformer usually associated with electronics controls. I know that current can be determined by the voltage across a resistor. You might throw in an SCR as well.
  16. K

    Bench Test Equipment

    I am thinking of purchasing an oscilloscope. But I think I want one of those brand new ones from Radioshack. It is has a single probe and it's the handheld type. Could you convince me of a cheap used oscilloscope?
  17. K

    inductors and arching

    I would not use one of those. My experience has been that many devices are implemented in hopes of prolonging the life of electronics components. You should really not need to do this. I think that the components are hardy enough to withstand negative transients.
  18. K

    low pass filter

    You forgot to mention the Bessel characteristic. By the way, these are just characteristics of the filter. Your filter will exhibit something close to one of these. Bessel is the most linear. Butterworth exhibits 20db per decade, which is a little steeper rolloff. The bessel is more like a one...
  19. K

    Beginners Transistor Help

    Should I use half power to get VCE? I want the beta to have maximum range and still be constant.
  20. K

    was Re:Ir-remote Now is: Op Amp discussion

    RI is your base resistor. The emitter resistance of the other transistor sees this base resistor. The impedance, looking at the emitter of a transistor, is resistance of the base divided by beta. RF is a collector resistor as seen by the output stage. You are right, there are no diodes. But...
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