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  1. K

    LC filters

    LC filters have good attenuation at low frequencies and are less suitable at higher frequencies. 40db/decade is the attenution. Is -3db the nominal attenuation for unwanted frequencies? Should the final attenuation be more or less than -3db in order to be finished with filtering.
  2. K

    Parallel LC

    Can a parallel LC, buffered from an oscillator, be used to determine the frequency of an oscillator? A parallel LC has only one resonant frequency.
  3. K

    MOSFET VGS

    How can MOSFET's be used in low voltage circuits when their VGS is high?
  4. K

    Light bulbs

    There are several ways to calculate light bulbs. Producing a 60W light bulb at 120Vac is one way. Measuring the resistance of the filament and the applied voltage is another way. But, the best way of all, is to determine the combined resistance and reactance, then apply the voltage and then...
  5. K

    diodes

    What diode does it take? Is it .7V or or less than that to turn a circuit off.
  6. K

    Direct neutralization

    Some transistors have a collector to base capacitor, but no inductor. Does that mean a single capacitor is acceptable and that sometimes neutralization is better? Would it depend on the frequency?
  7. K

    transistor biasing

    What is the lowest current a 200mA transistor should be operated at to prevent distortion caused by bias drift?
  8. K

    Resistors

    I must be wrong. But the high power resistors I bought do not have the value I thought  they had. Why must high power resistors have a value that are not what they say they are. I pay a lot for these high these things.
  9. K

    Analog oscillators

    Are simply constructed oscillators worse than oscillators used today? If they are, can it proved that the oscillators used today are without a doubt, and with no exception better in every aspect?
  10. K

    Linear response

    Most designs employ a large number of components and they generate a lot of noise. But error correction is linear in most cases. If a circuit is going to incorporate a microprocessor, why are smaller circuits limited to simple, linear error correction? A voltage regulator IC, a phase lock loop...
  11. K

    Filters

    What is the limitation of using filters that have better attenuation than capacitor and inductor filters?
  12. K

    zener diodes

    Why do voltage regulators require zener diodes? Can't circuits not use them? They can't be very effective with a low impedance load.
  13. K

    Neutralization

    Do IC's employ any passive circuits to reduce base collector capacitance? Why don't all high frequency circuits use base collector capacitance neutralization?
  14. K

    IC's

    Many integrated cirucuits have either no resistors or a few low value ones. So how much do they offer to designs? And many IC's have a wide range of operation. Would a small IC, like a voltage regulator, use many different types of transisotrs?
  15. K

    Amplification and loss

    Is loss in amplifiers any indication of design? Could you design a good amplifier with a lot of loss? A resistor causes loss, but no distortion. Many times I have had to reduce a signal after amplifying it. Is this a design problem?
  16. K

    opamp roll-off

    Is utilizing opamp roll-off a good idea? A 741 opamp has a gain of 100 at 100KHz, and the output is stable. External filtering components are most often used, so is opamp roll-off avoided? If I set the gain at 1000 and use a higher frequency to bring the gain to 500, would that be acceptable design?
  17. K

    Parallel A/D converters

    Can you compare the output of two parallel A/D converters and produce a better conversion? A comparator at the output of both A/D converters could produce more accuracy. An example is a differential opamp where common mode noise is eliminated by two inputs.
  18. K

    bipolar transistors

    MOSFETS and biploar transistors are very similar. MOSFETS don't have base current, which seems easier for design purposes. And their transfer curve is much better. Why are MOSFETS only used in output power stages?
  19. K

    Capacitors

    Doesn't a broken peice of wire cause capacitance?  How much distortion does a good size capacitor cause?
  20. K

    High frequency devices

    What makes a transistor circuit high frequency? Some are high frequency, but are the lower frequency transistors cheaper?
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