Search results

  1. K

    The backwards transistor

    I have an idea to develop a backwards transistor. I had this idea from the limitations I was getting. I wanted to operate the collector of a common base as an emitter. The reason is for the high impedance aspect of the collector as seen by the rest of the circuit. If I used an emitter, the...
  2. K

    Barrier potential discrepancy

    I thought I would give this new section a try. What about the diodes barrier potential. We all know that it measured with a meter and the polarity is that of the battery. I have read, though, that since the free electrons move from the N type to the P type, a negative potential appears in the P...
  3. K

    Ampliude and rate of change

    Is there any sort of modulation that uses the change of amplitude to give you a different rate of change. I know in AM the amplitude change is at the frequency of the message. But what about the amplitude of the signal itself. You know that whenver you gain a signal the amplitude increases and...
  4. K

    lm741 schematic diagram

    What I want to know is about the input stage. It seems there is a constant current in there. You know how you can have +7 and +7 on the inputs and have a 0 voltage out. I think there is a transistor there that sets the initial current at the base of the two connected transistors. If you have an...
  5. K

    AM demodulator diode

    How does this work. I can't see being able to change the frequency with a diode.
  6. K

    Weird circuit

    I have this weird circuit that I can't devulge too much about. It involves feedback and high current transistors and time delay. What I would like to know is if the beta of a high current transistor can change drastically. If I apply a large signal to the base, I get a large change in current...
  7. K

    Quick calculus question.

    The derivative of the sin 2X is the cos 2X. Correct. I was looking into the RMS and found some interesting stuff. If you take the RMS value and square it you get the average of the equation squared.
  8. K

    Simple RC circuit problem

    I am always coming up with new problems in electronics. Take a simple RC circuit and apply a triangle wave. Doesn't the signal divide down. This means there is a change in current. But on the other hand, the capacitor following the equation I = C dv/dt will have a constant current. So, must not...
  9. K

    Bad 7912's

    I have heard comments of 7912's not functioning properly and I am the next victim. What is going on with these bad parts. I didn't ask, but I think the person I talked to got their parts from another distributor. Has anybody experienced bad regulators before. Although the likelihood of getting...
  10. K

    I wish I knew

    I wish I knew that Electronics Lab offered a cheap oscilloscope. The one I bought off Ebay is a Madell. There is an interesting story behind it too. Right after a purchased the thing the horizontal went out. They were very kind in their repacement attitude and I received a new one. The only...
  11. K

    transformer windings

    I learned something new that I would like to share with everybody. I have a transformer with multiple windings. I thought that the taps off the different windings would return to each other. I found out that the voltage is just stepped down to the winding and that the voltage of the windings has...
  12. K

    Sine wave inverter

    In reference to the design of the inverter under the projects section, couldn't we replace the opamps with transistors? If the device that supplies the sine wave operates at 5v, shouldn't it be a 12v device? Could somebody hint at the design change because I feel that it is not designed entirely...
  13. K

    lm337t

    I have to fix the kit I have. The regulator seems to give out under higher currents after a brief while. I replaced the positive variable voltage regulator with the lm317t. This was easy to configure because I had the diagram. The lm337t which is the negative variable voltage regulator does not...
  14. K

    energy bands

    Current can come from either of two energy bands. What is the difference between current at one energy band and the current at the other energy band? They both consume the same amount of power, I believe. This is an open question to anyone that has a theory.
  15. K

    transistors

    I wanted to know if someone could corroborate this point in theory. When a signal is applied to the emitter of a transistor, it is divided by re. When the signal is applied to the base, it divides in the other direction re. This makes re division bidirectional. Am I correct about this assumption?
  16. K

    Many supply voltages

    I am in the process of a project and I am concerned that I may need many different supply voltages. I want to revamp this circuit I have to include the correct supply voltage. I really want to maximize this circuit and the constraints of a few voltage levels is not acceptable. How difficult is...
  17. K

    C problem

    I am using the Borland compiler and the examples don't seem to work. I make a call to a standard function in the correct header file and it says it doesn't exist. What could the problem be? I have had similar problems with serial communcations functions. I have a theory as to why it does not...
  18. K

    Latch triggering

    I have this latch I want to trigger, but it is very sensitive. So I used a pull down resistor on the input. The input to the latch is the ouput of a gate. This seemed to pull down the voltage so that it would not be so sensitive to trigger with a short duration pulse. Do you think this actually...
  19. K

    Shift Register

    Please let me know of a simple shift register with a clock input where the data propagates through the device. The one I bought shifts the first bit to the end and requires a shift out function.
  20. K

    MUX and DEMUX

    Why aren't multiplaxars and demultiplexars used for serial to parallel conversions? I understand that the operation of these devices could be used for conversions. Any help as to why would be appreciated. Are they used in chips to help complete these operations? I would like to see a...
Top