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  1. BobK

    Voltage to current converter circuit

    Do you even bother to read data sheets? That is an OPAMP that can only put out 23mA. Bob
  2. BobK

    Voltage to current converter circuit

    If you did, you did not tell us about it here. You mentioned trying two different opamps, one that could deliver a max of 50mA and the other that could deliver a max of 200mA, and then you complain that you cannot get 1A. Find a Audio Power Amp (which is NOT the same thing as an opamp) that...
  3. BobK

    Arc of LED lights...any ideas?

    Great minds think alike! I was wondering the same thing. If the wires are close to the middle of the string, you might be able to cut notches between each LED and bend it. But, since you mentioned that the NEO pixel 60 ring is the right curvature, why not use it? How many degrees of arc...
  4. BobK

    Transmit and receive parallel data through radio link

    The solution to this is called a start bit. When not scanning, you should always transmit 0 (or 1, which is actually what is sued for RS-232.) Then then it is time to start transmitting data, you transmit the opposite for 1 cycle. The awakens the receiver and readies it to receiver the data...
  5. BobK

    Transmit and receive parallel data through radio link

    I think you and I are not speaking a different language (though both look suspiciously like English.) No, I mean the bits output from the encoder. Your circuit will sequentially link each input bit to the output bit for one clock cycle. I.e. first clock cycle: bit 0 input of encoder appear...
  6. BobK

    How Transistors Work

    Exactly the same thing can be said about the base-emitter voltage. You can have a Vbe of 1V which would allow a large current to flow, but if there is a collector resistor it might limit the collector current to a much lower value. Bob
  7. BobK

    Starter Solenoid Switch

    Duh. Mind fart. Bob
  8. BobK

    Transmit and receive parallel data through radio link

    So the transmitter is constantly transmitting bit 0 until scan is started, right? So, suppose bit's 1, 2 and 3 have the same value as bit 0. How does the receiver know that the scan has started, it sees no change until bit 4? Bob
  9. BobK

    Starter Solenoid Switch

    Your picture is a switch, not a relay. You cannot have a relay with 2 leads. The starter solenoid draws a large current and operates infrequently, so a relay is probably more appropriate than an electronic switch, though there is not reason you could not use an electronic switch as long as...
  10. BobK

    Clock generator

    You can get a 1MHz oscillator in a single package as well. Bob
  11. BobK

    Arc of LED lights...any ideas?

    I'll go out on a limb here. I don't really know, but, as I understand it, these are just linked together in series, so they can be cut anywhere. In fact, if you read about the ring, it consists of 4 arcs that are soldered together to make the ring. If you need a 90 degree arc, that is the way...
  12. BobK

    Transmit and receive parallel data through radio link

    I did not analyze your schematic in detail, but I think this is what you are doing: A signal called <scan> starts the scanning of the (up to 8) input channels and outputting their value to the data input of the transmitter. The problem with this is that there is no way to sync the receiver...
  13. BobK

    [free energy] is there hidden power in plain sight?

    The only thing you can do by varying the number of turns of wire is increase voltage at the expense of current or increase current at the expense of voltage. And power is voltage x current, which does not change. Except that power is lost to the resistance of the wires, and cannot be...
  14. BobK

    How can I generate 0.1v output?

    Could you measure the resistance of the probes as they will be used? If you think 6uA is required, that would translate to 16K Ohms. I doubt that it is that high. And by the way, you cannot specify both current and voltage. Bob
  15. BobK

    Laser dalek!!

    Yep, I am here! How much current does the green laser need? What transistor and resistor did you use? Bob
  16. BobK

    RGB LED Control

    So you want discrete colors for different voltage ranges: 0-2V = blue 2-4V = ? 4-6V = ? 6-8V = ? 8-10V = ? 10-12V = red right? edit: I think fading them would be more fun, and with a micro would much less hardware than the 6 ranges you want. Bob
  17. BobK

    Transmit and receive parallel data through radio link

    Yes, it would not work. Bob
  18. BobK

    RGB LED Control

    Change color could mean anything. You only said blue at 0V and red at 12V. What colors in between? If you want it to fade from blue to read through all mixes of red and blue, that is fairly easy. If you want it to go from blue to green to red through all the colors of the rainbow, a little...
  19. BobK

    RGB LED Control

    Okay, I missed the part about not wanting to use a micro. Much more difficult without one. Bob
  20. BobK

    Looking at an arduino

    No, it doesn't, but they would be lying if they called it Arduino. Bob
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