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  1. K

    Very long RC time contant!

    Yes, I've seen the pictures. It's the only way I know how to determine phase shift. That equation may as well not be tailored to the simple circuits I build. Maybe you take the 2pi out there too.
  2. K

    Stupid observation

    No, I don't believe so. A wrist strap will not protect anybody from the AC outlet. Even if the current limiting resistor approaches infinity.
  3. K

    Very long RC time contant!

    Wow, not once have I ever read anything about how you arrived at that. If I had to include phase into the voltage divider, I would be stuck. And so would my books author. Just remove 2pi from the reactance equation. It works perfect and with no surprise. And you know, discovering this a bit late...
  4. K

    Very long RC time contant!

    Audioguru, that phase thing has nothing to do with impedance and voltage drop. I have not been building circuits for a long time, so it took me a few to figure it out. You take the 2pi out of the reactance equation to get the voltage divider.
  5. K

    Very long RC time contant!

    What is funny, if you start a sinewave on an RC just up to 90 degree and stop, the capacitor still gets voltage, rather than remaining at zero. It's not going to wait until the input starts to go down, because it may not go down. I plotted RC phase shift on paper one time using a triangle. I...
  6. K

    Disadvantages of simple filters

    I think most designs should go for chebychev until it becomes a nuisance.
  7. K

    Very long RC time contant!

    Audioguru, should I just go back to my lab and learn to measure resistance with an ohmeter all over again. Maybe I could be a cook for the electronics guys at work. Just joking Kevin
  8. K

    Disadvantages of simple filters

    Try using a passive filter at a high frequency. It doesn't do much. 20db per decade.
  9. K

    Very long RC time contant!

    I don't think you meant equal impedance, that would be half the voltage. Your thinking resonant frequency.
  10. K

    Very long RC time contant!

    The triangle is the trick. It's not seen using a sinewave. The low frequency triangle allows the other side of the capacitor to go to bias too quickly. The instantaneous voltage of the input charges the capacitor like DC.
  11. K

    Very long RC time contant!

    The RC time constant must be long enough with repect to the signal time to cleanly pass the signal through the capacitor. Is this statement true or false? Answer : True. I wanted to revisit this topic because I was sharply denounced last time. Now, I know the truth. Any takers?
  12. K

    low current transistor bias

    Without a lot of thought, I find the variable current voltage thing hard to imagine. I understand what your saying. It reminds me of the voltage source versus current source thing. Thanks for the tip, I think...
  13. K

    RMS

    Peak power is instantaneous. RMS power takes the peak, the low, everything in between, and gives you one value. It is, one value, because the RMS voltage is, one value. Square the RMS voltage and divide by the resistance.
  14. K

    Inductance

    Voltage induced is equal to L di/dt. For a capacitor current is equal to C dv/dt. I never ever pay attention to them unless when speaking in general terms. I = C dv/dt caused me a lot of trouble for several nights.
  15. K

    low current transistor bias

    No, the collector current is like 1mA. How do you mean an AC current versus AC voltage? Bad spots are manufacturing shortcomings. I really don't know much about the physics of transistors, but I can tell you all is not perfect. When I first started electronics I studied the book, then I used a...
  16. K

    RMS

    Mathematically, you have to remove the voltage offset to calculate RMS. Also, RMS is kind of like the Average, but it stinks mathematically. The equation get's squared, which creates a totally different equation. Then you find the area, then you take the square root. The only thing I know is...
  17. K

    low current transistor bias

    The schematic is a very large text book offering of an AM transceiver. It has a mic input to an antenna for transmit, then the same antenna input for receive to a speaker. It's almost all bipolar and they are probably of average current. Your right about the gain. But I went a step further. The...
  18. K

    low current transistor bias

    I have this schematic with unknown bipolars. The transistors are biased at an extremely low current and higher voltage. Without the ability to have a large change in collector current, as it's biased at like 1mA, the input signal and output signal are destined to be small. Even the final amps...
  19. K

    common-mode??

    Also, noise can appear common mode at the inputs. There is also input capacitance which, if the noise is a higher frequency than the wanted signal, can aid in removing the noise.
  20. K

    Stupid observation

    I have heard of using rubber mats and special boots when working with high voltage.
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