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  1. L

    Simple Combinational System Design

    Here are worksheets for the truth table and the K-map. In the K-map note that the olive-colored squares are required by the truth table, and the white squares are don't-care conditions. The blue squares are don't-cares which have been assigned a value for optimizing the minimization. One...
  2. L

    Poles and Zeroes of a Transfer Function

    I never did fully appreciate why poles & zeroes are considered important, except that they allow the Bode magnitude plot to be estimated and sketched. However, with a computer algebra program it becomes easier to numerically generate an accurate Bode plot than to make a rough sketch from the...
  3. L

    Poles and Zeroes of a Transfer Function

    The following reference should answer your questions - http://www.ee.up.ac.za/main/_media/en/undergrad/subjects/eli220/polezero.pdf When you have a pair of complex conjugate poles in the transfer function, there are two poles at the same frequency that together will contribute -40dB per decade...
  4. L

    DC speed control Qs

    The pot performs a particular function in the circuit, and might actually be discernible if there were a schematic to examine. If there were also a schematic for the pedal controller then it might be possible to determine how to substitute the pedal for the pot.
  5. L

    Circuitry not accepting load

    Can you explain what is the purpose of R1 and R6? I can see that you have made a power supply with an internal resistance of at least 20K ohms. Just how much current were you expecting the load to draw through the 20K?
  6. L

    Schmitt Oscillator

    The two-gate oscillator is discussed in Fairchild AppNote AN-118 "CMOS Oscillators" (page 3). http://www.fairchildsemi.com/an/AN/AN-118.pdf It may be difficult to obtain a general formula for frequency due to the dependency on the threshold voltages which have a wide tolerance, see attachment...
  7. L

    filter circuits

    How much ripple was there in the circuit with the single inductor or capacitor?
  8. L

    What is the best way of solving the circuit?

    Possibly. But the OP didn't seem to have sufficient grounding in nodal analysis to be able to know what to do with cryptic hints. The OP seemed to need an example to demonstrate that nodal analysis was possible and even the best way to analyse this circuit. Perhaps I should have constructed...
  9. L

    Trouble with diffrential amplifier output

    I suggested the 10K resistors before I looked up the parametric curves for the output sink current. It appears that pin 1 will have a constant 2.3 volts which is fed through the two 1K resistors to the current sink on pin 7. The current is roughly 2 mA. From the sink curves you can see that...
  10. L

    What is the best way of solving the circuit?

    The equations for nodal analysis are the easiest to write, and least likely to make mistakes. Using a symbolic algebra program allows for a minimum busy work solution. See attached analysis. The node equations are written for each of the identified nodes: V1, V2, V3, & V4 with currents I1 &...
  11. L

    Trouble with diffrential amplifier output

    What happens if you substitute 10K resistors for the 1K resistors in the feedback path? The attached parametric curves should explain why the output does not go below 0.7 volt. In fact it will never go to zero, but will get closer to zero if the output current is lowered.
  12. L

    Quick question regarding op amps

    Using a voltage divider to create a virtual ground does not create a third 'rail'. What it creates is a high-impedance voltage source that is only suitable for driving the reference inputs of op-amps and comparators. If your circuit requires a low-impedance ground, then you need to use two...
  13. L

    Tilt Sensor Project

    Perhaps you need a single-axis inclinometer? http://en.wikipedia.org/wiki/Inclinometer Do you need to read an angle or just sense a limit? If it is just to sense a limit then you could hang a half disk from a pivot point. The disk will always hang straight down. Make it from clear plastic...
  14. L

    Find suitable capacitor for wind energy device

    Since this is a materials science problem, should we assume that the task is to select the dielectric material and design the physical parameters of the capacitor? Is it sufficient that the capacitor just store 150kWh (540MJ) or do you also have to address the problem of getting the energy out...
  15. L

    Ohm's Law or not Ohm's Law... That is the question

    If you were to direct your studies to advanced calculus so as to better understand the Laplace Transform, and to advanced circuit analysis so as to better understand operations in the complex frequency domain, then you would know why circuit analysis is never done in the manner stated above. I...
  16. L

    Ohm's Law or not Ohm's Law... That is the question

    It is the miracle of modern mathematical transformation that will take something complex and make it obey the simplicity of Ohm's Law. E/I=R E/I=Z
  17. L

    Electronic Tanpura

    There is an Android App for that. Tanpura Droid by Swar Systems. Free. https://play.google.com/store/apps/details?id=com.swarsystems.is&hl=en
  18. L

    Ohm's Law or not Ohm's Law... That is the question

    "That Generalized Ohm's law (which is not Ohm's law)" BobK still clings to his ancient religion. "applies only in the case the voltage is a sine wave of a specific frequency" Not a true statement when the circuit analysis is conducted in the complex frequency domain using the complex...
  19. L

    Ohm's Law or not Ohm's Law... That is the question

    That same entry on Wikipedia makes the following statement: "This form of Ohm's law, with Z taking the place of R, generalizes the simpler form. When Z is complex, only the real part is responsible for dissipating heat." I am talking about that form of Ohm's Law.
  20. L

    Ohm's Law or not Ohm's Law... That is the question

    In what way is saying, "Ohm's Law also applies to reactance as well as resistance." equivalent to saying, "Einstein's general relativty equations are the same as Newton's law of gravitation."?
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