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  1. K

    hv polarity indicator/ voltage optimizer

    Are you using just a transformer?It's interesting that voltage and current are used so often in electronics, yet it's the voltage which produces the arc. How does a generator produce a low voltage AC which can be converted to a high voltage AC? In other words, where does it get the current? Is...
  2. K

    regulators

    I am bewildered by all the different types of regulators on the market. Regulators are simple to construct if you are dealing with one small signal application. What are some examples of the different types of loads one might see in electronics?
  3. K

    ttl or gate

    You need more gain. Try using a push-pull. What an OR gate uses is a phase splitter. Which works the same as a push-pull. A push-pull is what an opamp uses. The formation of logic begins to be a little trickier, doesn't it.
  4. K

    basic capacitor question

    Has anybody seen the sawtooth wave generator that uses a PUT in parallel with a capacitor to get rapid discharge. The input overdrives the PUT past a short, but allows voltage across the capacitor. When the input drops, the capacitor will rapidly discharge.
  5. K

    Impedance matching

    This will require the formula wavelength = (.67)100x10E6 / frequency What do you do with the wavelength? You also have to incorporate the load resistance. I would make the length some fraction of the wavelength. I would assume the load to be a short because it will be closer to a short. If...
  6. K

    OPAMP questions

    I must elaborate on an earlier statement. The input capacitor, associated with phase shift, does not inherently change the characteristic of the opamp. Instead, it changes the input signal such that it will not produce 40db roll-off. This makes the graph misleading because it shows the 20db...
  7. K

    HELP ? ATX PSU LEADS

    You can't predict how the motherboard will be affected. It will affect the performance before anything. What you have, with a bigger wire, is an inductor between the transistor/resistor and the supply voltage. This might make the gains higher.
  8. K

    My 120 Watts Power Inverter

    You have to account for the time when, after the input saturates, the voltage across the inductor drops. So it would seem that cutoff should happen right after saturation, but it can't. This creates a time after saturation that determines shape of the ouput.
  9. K

    Project Help

    You certainly need an oscilloscope to determine how the siganal is changing. It might vary the pulse width(duty cycle), the pulse time, or the pulse amplitude. This is going to require a more complicated matching circuit. I would consult an electronics guy to develop the circuit.
  10. K

    A/D Converters and Shift registers

    Shift registers are just serial devices. You would have to wait for them to fill up before taking a parallel output. They require you to clock in the data. The ouput of the A/D is going to be serial with a time base dependent on a clock or the signal. A multiplexar is similar to the shift...
  11. K

    Power Supply +5v with Zener

    From my circuit, which is similar to Siddharths, the input signal is drowned out by a capacitor and the zener gets it's voltage from the ouput through a resistor. Interestingly enough, the voltage of the darlington is high, making the current low. The rated current is 1.5A. I understand the...
  12. K

    OPAMP questions

    Remember that an oscillation has to do with a change in polarity across the input. This is what causes the voltage to go in either direction. An oscillation is simply anything around an opamp circuit that would cause the input to change polarity. This could include the feedback. Any good...
  13. K

    An SCR/TRIAC tester

    Has anybody seen the circuit with the PUT across a capacitor across an opamp. This generates a sawtooth. A rapid discharge of the capacitor. I think these 5 layer devices pose a serious physics debate. You know the construction lends itself to PN voltages even though we treat them as a short...
  14. K

    RJ45 network card to IR

    Is the signal fed through the capacitor and inductor? This makes for a changing voltage at the negative terminal. To make it work for me, I would ground the 9v negative terminal to start.
  15. K

    A stand alone sine wave generator using Atmel chip

    I would bet there is a debate regarding sinewave generation. I have seen an example in this forum that uses a square wave, but with an added DC level during the middle part of the transistion. They called this a modified sinewave. I agree that a squarewave can be used to make a sinewave. But I...
  16. K

    LCR circuits

    Has anybody seen the calculations for the more complicated LCR circuits. I understand the basic circuits, but any addition is not well illustrated in the book I have. Take a simple series LC and parallel the capacitor with a resistor. This goes beyond what I have seen being calculated. If a...
  17. K

    Power Supply +5v with Zener

    The circuit I have gets it's zener voltage from the output. It is a commercial power supply.
  18. K

    Power Supply +5v with Zener

    Thank you for correcting me audioguru. The only difference is that the zener gets it's voltage from the output through a resistor.
  19. K

    Power Supply +5v with Zener

    Siddharth, you know the circuit I am talking about. The zener, because it gets it's voltage from the ouput, will drown out the signal at the emitter. The base still has it's signal. So the signal at the PN junction is really onesided. But if you use a resistor, then the function will still be...
  20. K

    A stand alone sine wave generator using Atmel chip

    A sine wave is sometimes made from a triangle wave. This would mean the use of an integrator. I would use a transistor and a capacitor on the collector to construct the triangle wave. Then a simple filter would be required. The filter would be to attenuate the low frequency of the triangle. Use...
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