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  1. BobK

    APOLOGIES TO THE GROUP

    About the return of wind generators: https://www.google.com/amp/s/amp.theguardian.com/environment/2012/feb/29/turbines-energy Summary: lifetime return of 20 to 25 X the energy used to build and install. Break even point, 3 to 6 months. Bob
  2. BobK

    Spinning/rolls count device

    You need a microcontroller to interpret the info coming out of the sensor and format and write this info to the LCD. This also requires programming. Bob
  3. BobK

    battery troubles

    What 12V batteries are you using? Even an AA sized cell can supply 1A, at least for a short while. And a 12V Lithium Ion battery can supply 10s of Amps. How long does it have to run? Bob
  4. BobK

    Spinning/rolls count device

    The gyro is a sensor to count the rotations, not the thing he is measuring. Bob
  5. BobK

    Help in deciding method for de-modulating? a signal to extract one frequency!

    There are two general methods you could use, one analog and the other digital. The analog solution involves a set of bandpass filters, one for each frequency, and each followed by a peak detector. The digital solution would involve some form of Fourier transform. Bob
  6. BobK

    What does your workshop / workbench look like?

    Why do you think it took me days before posting a photo? It took me that long to get it to where you could see anything. Bob
  7. BobK

    What does your workshop / workbench look like?

    Okay, here is my work area. A bit less equipment than Steve!
  8. BobK

    Can Power Supply Sink Current

    Rechargeable batteries can, within limits. Bob
  9. BobK

    Easiest method to convert analog ac voltage or frequency to digital 0-5v dc?

    Do you need to measure both the frequency and the amplitude, or just the frequency? Bob
  10. BobK

    What does your workshop / workbench look like?

    In my case, I am sure the lovely wife Morticia would love it! Bob
  11. BobK

    Serial communication problem.

    Okay, a little more research find that there are 3 varieties. 2N2222 metal can P2N2222 TO-92 euro pinout CBE PN2222 TO-92 american pinout EBC You might want to try reversing the 2N2222 ones to see if it works. Bob
  12. BobK

    Serial communication problem.

    Are you sure you have a 2N2222? The ones in TO92 cases are generally PN2222, wtih pinout EBC. I don't know if there even exists a 2N2222 in TO92. They cone in an old metal can. The BC547 is CBE. Bob
  13. BobK

    Convert ADC code to a voltage

    If you want to convert the output of an ADC to a voltage, why not just use the input instead? Bob
  14. BobK

    Question about Diode potential of anode with respect to cathode

    Which is why ideal diodes do not exist. Bob
  15. BobK

    Linear or switching regulator?

    Well, it depends on the current. If you are using only 1mA, the wasted power is only 19mW , and a linear regulator is a no brainer. The changeover point is probably somewhwe in the region of 50mA, which results in 1W of loss, which can be handled by a TO220 case woth no heat sink. Bob
  16. BobK

    Understanding Datasheets

    The gate of a MOSFET is essentially a capacitor, with the source being the other terminal. Therefore it does not draw any current when the voltage on it is steady. Current comes into play only for fast switching times. Some will need over an Amp of current, for nanoseconds, to achieve their...
  17. BobK

    Network Time Display

    And more power. Bob
  18. BobK

    Need to drain off curent.

    There is something I don't understand here. Are you saying that, to go down, you supply the motors with the same polarity as you do when going up, but lower voltage so that the motor slips backwards? If so, the motors are not just stalled, they are going backwards. This will use more current...
  19. BobK

    Need to drain off curent.

    Limiting thr current can only make it worse. You need a power supply with a higher current rating. Bob
  20. BobK

    PWM Control with Shift Register Support for 3w White LED's

    Isn't Ebay great, Adapters like that used to cost 10 times as much as the part they were adapting. Bob
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