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  1. K

    urgent (counter question)

    What do you mean it's not exactly like that. Your explaination is identical to mine.
  2. K

    how can i produce 15kV from 15V DC

    You use current to bring the voltage up. Accordingly, you can use even a DC voltage to bring the voltage up to a maximum peak to peak. However you cannot take this and rectify it nor filter it. You cannot rectify because the oscillation is not AC and you cannot filter because there is not enough...
  3. K

    urgent (counter question)

    You want asynchronous when the time is not crucial and you want a minimum number of devices. Use synchronous when the time is crucial but will require more devices. There is a minimum amount of time delay between devices when using synchronous.
  4. K

    RMS

    square the RMS value. That gives you the average of the function squared. Multiply by pi and that gives you the area. This area is different from the original functions area. Maybe you are getting the average of the original function which .636VP. In which case this is the true DC value of the...
  5. K

    Weird circuit

    And one final update. The impedances do win. The calculations even with feedback prove to be true. It was not the signal amplitude. It was a mere fact of impedance. However in my circuit, I am going to allow the feedback signal to produce the same change in base current as the signal source. The...
  6. K

    Weird circuit

    There is another update to my circuit. It is amazing that the calculations prove to be correct. The problem I was experiencing was from excessive signal amplitude. You should probably use less than 1Vpp when analyzing your circuit.
  7. K

    Weird circuit

    There is an update to the circuit I posted. It works fine. I am still getting a halving of the signal but I think it is arbitrary. It was not a change in beta that was the problem. It has to do with source of the signal and the feedback which is secondary. You can only create a certain amount of...
  8. K

    ECG for home use

    It is my opinion that in real ECG monitors, the filtering is suited to filter out the part of the ECG that is not wanted.
  9. 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...
  10. K

    Quick calculus question.

    I think you are wrong about that. If you take 90 degrees for example you get the derivative of sin90=cos90. Therefore the derivative of the sin 2x=cos 2x.
  11. 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.
  12. K

    Logic Level MOSFETs

    All you have to do is look at a digital circuit to tell that the logic level is a nuisance to the circuit. So what they do is use the logic level the best way they can. The result is high gain. The phase splitter handles the high gain while the input transistor acts like two diodes to handle the...
  13. K

    TRIAC question

    A triac can be tricky because it only requires a pulse of the shortest duration. When it conducts, in either direction, the voltage might be around .7 volt. When the voltage goes below .7 volts or when the gate voltage produces a reverse bias, conduction will cease.
  14. K

    help! transistor as diode

    I have seen the base emitter diode used in practice. I have also seen it used in a circuit diagram. This is a bizzare thing because the transistor was not meant to operate like two diodes. It is a current amplifier. The two diodes exist because that is how a transistor is made. The reverse...
  15. K

    Laser Applications???

    The time there at 300 meters is 1us. The time there at 1 meter is 3.3 ns.
  16. K

    Primary current waveshape

    If your regulator is not working properly then you might have an RL type circuit. Also the PW of the driving signal will allow for discharging of the inductor. But I think that if you are getting weird voltages then it is probably your regulator that is at fault.
  17. K

    Stupid op-amp question

    He is applying the .7v through the 10kohm resistor which will make the input .86v. 1-.86 x 22=3v.
  18. K

    Stupid op-amp question

    Try using the recommended load of 10kohms to the negative supply. Apply the 1 volt to the noninverting input directly. Then apply the .7v to the inverting input through the 10k. The voltage on the output will be 3V.
  19. K

    Digital meter circuit with rs232 output?

    Any of the electronics devices can be used in the millivolt range. In fact the uV range. They are presumed very accurate in terms of the voltage they exhibit. When you say measure, I am assuming you want to convert the voltage to a display. So you might use a device set to trigger at a...
  20. K

    Question on the 0-30 VDC PSU...

    I am not sure you can get the current requirement from 150VA. The transformer is rated for the current. The current is RMS. So the DC current you will be able to get after rectification for a 3Arms transformer will less than 3A. Maybe around 2ADC. The peak current for a transformer can be very...
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