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    Simple Schematic - but components may not even exist! [600VDC]

    Connecting to a string of resistors using a multi-tap rotary switch would be good, and actually being able to find a rotary switch rated for 100mA at 600VDC would be even better. It may be necessary to build a custom rotary switch as part of your device. Look at how laboratory switches were...
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    Simple Schematic - but components may not even exist! [600VDC]

    The circuit diagram shows a 2600Ω resistor possibly driven by 600 VDC depending on the connected load. Power dissipation in the resistor will be V²/R = 138 watts. Maximum current will be I=V/R 600/2600=230mA, well within the rating of the fuse. Consider that the resistor should consist of a...
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    Trying to solve exercise in art of electronics involving transistors and diodes

    Here is a different opinion from http://www.allaboutcircuits.com/textbook/semiconductors/chpt-4/common-collector-amplifier/
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    Trying to solve exercise in art of electronics involving transistors and diodes

    Review section "2.02 Transistor switch" on page 63 in the Art of Electronics where it explains a transistor switch in saturation.
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    Circuit design for high resistance sensor measurement

    Working with signal conditioning at 100MΩ is more of an art than science. A stray fingerprint on a circuit board can leave a conduction path with less resistance than the circuit components involved. Even ordinary handling of a 100MΩ resistor under less than clean-room protocol can...
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    Thevenin voltage

    In that case I can't see anything wrong. In the transition region from forward conduction to reverse breakdown there should be no current flowing in the Zener diode (ignoring leakage current) so the voltage polarity would be as though the diode were not present in the circuit.
  7. L

    Thevenin voltage

    Where does the problem indicate that the Zener diode should be forward biased?
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    Adjustable Schmitt Trigger Circuit Help

    The FF should be wired to provide the hysteresis that would normally be accomplished by positive feedback in the single-comparator circuit.
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    Thevenin voltage

    Indeed, the given answer for Vth is incorrect. However, when one is looking for the voltage, why calculate the current? Why not calculate the node voltage instead of the mesh current? But since this problem is a simple cascaded voltage divider, one can use a voltage divider approach instead...
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    I want to see if my boolean algebra is correct.

    The usual method to get logic from a truth table is to generate a Karnaugh map for each column (output) in the table, minimize the K-map, and implement the result in gate logic. Three examples are attached for the R1, Y1, & G1 outputs. (But did not ask TINA to provide the gate implementation.)
  11. L

    5 Ways to Harness Free Energy

    Maybe not ... if one has a free source of bleach, and aluminum, and copper - to be liberated from the tyranny of corporate power utilities.
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    the concept about to basic electronics.I need basic concept of subject electronics

    The study of electronics is built on a foundation of circuit analysis. A basic, yet complete, presentation of these basic principles can be found in "Circuit Analysis for Dummies". But be warned, every page covers a simple and important concept. If you are the type who can easily absorb the...
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    How does an op-Amp make the inputs the same?

    Wrong question. It is Vdiff that sustains Vout. Vout cannot increase above 1.9996V with the given parameters. That is the error from the ideal case caused by having a less than infinite open-loop gain.
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    How does an op-Amp make the inputs the same?

    While the usual assumption is that the virtual ground voltage is equal to ground, in reality that is not the case. In the attached figure the exact voltage for the virtual ground is calculated for finite gain but an otherwise ideal op amp. Putting the op amp in a common configuration with the...
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    Forgive me for I know not what I do....

    This seems like it might be of interest: http://pdxcug.org/commodore_joystick_switch.asp
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    RC filter

    What is the corner frequency of the RC filter? What is the source impedance of the pulse driver in the ON state and OFF state? How fast is "real time" response?
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    sample and hold pulse source?

    Without a schematic it is difficult to evaluate the problem. Are you using an edge-triggered monostable, or still using the 555? The 555 datasheet contains the following helpful advice: "NOTE: In monostable operation, the trigger should be driven high before the end of timing cycle."
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    Synchronization of pulses

    If you need synchronized pulses from identical timers, why are you using more than one timer?
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    Resonance Frequency

    So I found the transfer function from the circuit node equation and made a Bode plot for some representative RLC values. But it is not too clear what is useful about the calculated 'resonance' frequency.
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    Resonance Frequency

    It should be a good assumption that resonance is that point where the current flowing through the RLC network has no reactive component. Since I=V/Z, take the reciprocal of the RLC impedance, multiply the numerator by the complex conjugate of the denominator, isolate the imaginary component of...
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