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  1. K

    Working of a PLL

    I think a PLL is basically just another circuit that is tapped in a location such that you can you can insert a signal or tap one. It's kind of like taking a signal from wherever else and inserting it harmlessly into another portion of the circuit. It's done all the time.
  2. K

    Shift Registers

    Shekhar, the rate the data enters the device will affect how much storage you need. If you start retrieving the data as soon as 1 second is up, you will have compiled a whole mess of data. But that data will leave consecutively with the first data put into the device. So if you clock the data in...
  3. K

    Relatively new, looking for some basic answers.

    The transistor uses a low base current to generate a higher current flow from collector to emitter. That's all. It does this because of how it is constructed. I think it is because of the voltage that exists betweeen the collector and emitter. Whenever you get conduction from the base to...
  4. K

    Shift Registers

    Shekar, to get that much delay you might as well store it in RAM and retrieve it pending a real time clock.
  5. K

    Negative charge pump

    Yeah. I think the amplifier is a pushpull. The volume is adjusted internal to the chip. The amplitude of the input is taken into account and it drives the pushpull.
  6. K

    Volume

    This is the circuit I was looking for when I posted under the negative charge pump. My circuit was to generate the negative supply from the 0 and 12. I was going to use this to generate an AC for the speaker. Audioguru led me to believe the circuit could not be accomplished for lack of power. It...
  7. K

    FM WAVE PROPAGATION

    I think that all antennas radiate in all directions. I also believe the reason behind focusing the signal is because of the power that is wasted from trying to generate a signal in all directions. This means that all of the power put into a signal will be used in the transmission. This is ideal...
  8. K

    problem with a rectifier

    I think you are terribly wrong Audioguru. I have in fact experienced this phenomen. Please enlighten me. It does make sense that the resistance of the diode is part of the filtering RC. When the voltage of mains reaches peak, the capacitor is charged. This is a peak to peak result that is...
  9. K

    capacitance meter

    Thanks Audioguru, that is something I need to suspect. I am not really comfortable when it comes to clamping but I believe your statement to be true if the thing works. Isn't the design a little bizzare. I would just expect something different from a capacitance meter. It seems like the circuit...
  10. K

    problem with a rectifier

    Typically you will have large ripple if the diodes don't produce enough impedance. Try using larger diodes and you will get less ripple. Then you should have a stable DC to run the lm317. It also sounds like you have turned the lm317 into a voltage follower. This happens if you hook the...
  11. K

    capacitance meter

    I took a look at this circuit and found it odd in a couple of ways. What is the purpose of the two diodes. It seems that one end of the capacitor in question is charged to 5.2volts and the other end swings from 0 to 5.5volts. While I understand discharge through the ammeter I don't understand...
  12. K

    Transformer Power Rating

    The 8Amps is the maximum RMS current that the wire of the transformer can withstand. This holds true for both the primary and the secondary. You might be tempted to use the average value but I think it is the RMS.
  13. K

    Ground a astable 555 at startup

    A simple trigger can be constructed with a resistor and inductor to ground. When you turn the power supply onto this circuit, the result is a pulse. This is a better way to trigger your oscillator. Just design the oscillator as usual and use this trigger to generate the reset. The pulse will...
  14. K

    Relatively new, looking for some basic answers.

    Storing DC without the reoccuring charge of the input is not a good method. You are relying on the current from the capacitor solely and the energy stored is not that great. energy=.5CVsquared.
  15. K

    Need help with really simple thing!

    C1 is the oscillator portion of the circuit. It charges from the apllied 12volts and discharges from the last transistor that turns on when there is 12volts and turns off when the discharge reduces the voltage at the first transistor.
  16. K

    Logic Gates IC Chips

    To test the opamp I would just adjust the offset and determine that it switches in polarity. In the case where you don't have an offset null, you will have to apply direct voltage. Don't worry about the values, just check to make sure the polarity of the output reflects the input.
  17. K

    Ground a astable 555 at startup

    Just as a side note, there is normally a correct way of doing things. The two circuits only produce similar results. Besides, why don't you just use the switch to supply power to the 555. This way it will oscillate the moment you press the switch.
  18. K

    Relatively new, looking for some basic answers.

    A transistor can be thought of as a current amplifier. Because there is multiplication involved, the change in current is greater. That is really what the transistor is about.
  19. K

    Negative charge pump

    Audioguru, I simply removed the transistor and increased the voltage output from -10.3volts to -13.3volts. I know what you mean by the NPN that transfers -7.3. I think that the resistors could need fine tunning. What is interesting is that in spite of the fact I got -13.3volts, there was a...
  20. K

    Negative charge pump

    Hey audioguru, everything is copasetic. Here is my lower current negative charge pump. The first part is very similar to the second delivering a total of -10.3 volts from 0 and 12. Take a look. The NPN's are 3 A becuase that is all I have left. The PNP's are about 500mA. The capacitors should be...
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