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  1. (*steve*)

    why is this comparator triggering on falling edge?

    You also need to look at the maximum range of input voltage on the input pins. For example I bet it has limits on how far outside the supply rails they can be.
  2. (*steve*)

    Anyone ever build a DC to AC inverter ? Needs to run on 32v DC

    Also, you'll note that the circuit you have used PNP transistors. If you do your research you'll find it was designed for germanium transistors. Whilst silicon transistors are better in many respects, the BE breakdown voltage is one area where they are not. It is quite possible that if you...
  3. (*steve*)

    Anyone ever build a DC to AC inverter ? Needs to run on 32v DC

    The first change would be to use an approx 60V CT transformer. That may be hard to find.
  4. (*steve*)

    why is this comparator triggering on falling edge?

    One important reference is the datasheet. It will give you limits on input voltage ranges. If your circuit exceeds these, you should only be surprised if it continues to work correctly.
  5. (*steve*)

    Want Guidance for my Arduino Networking

    With nodes at that distance from each other, they will almost certainly require high gain antennas at the remote nodes. It is thus also very probable that the remote nodes will not be able to hear each other. In this case, any form of collision sensing is likely to be totally ineffective. You...
  6. (*steve*)

    dissipation in a zener diode

    The dissipation is V*I. If you have a datasheet for the panels it might have a V vs I curve at a nominal 100% solar irradiance. From that you can determine a current at 40V. Let's say it's 5A. That will give you a power dissipation of up to 200W. It may be very expensive to get a zener with...
  7. (*steve*)

    A simple one with LED strip

    *Some* cheap strips from eBay work fine.
  8. (*steve*)

    A simple one with LED strip

    Running them at maybe 50% of their "rated" current will make them last a lot longer. Because of the non-linear nature of LEDs, this may require only a small change in voltage. It is most easily done by placing a low value resistor in series with the strip. If you look on the strips, there...
  9. (*steve*)

    DC-DC Converter

    Perhaps you can upload those attachments again. It looks like you deleted them -- don't do that :-)
  10. (*steve*)

    what is the difference/s if i use a thyristor instead of the transistor in this circuit?

    The diode doesn't prevent back EMF, it prevents the back EMF from doing damage. "A coil" in this sense is referring to a device with inductance. Inductance means that it has the property of resisting the change of current flowing through it. (If you understand inertia, it is somewhat...
  11. (*steve*)

    Carbon monoxide sensor

    Yeah but you ignored the most important part of what I said. And what at I've been saying for most of my posts.
  12. (*steve*)

    Carbon monoxide sensor

    How can I write this more clearly... WHAT ABOUT THE OTHER GASSES IT IS SENSITIVE TO?
  13. (*steve*)

    Help with powering a circuit board

    If disagree with that. Most chargers these days are switchmode power supplies which have pretty good output voltage regulation. This will almost certainly be true if the charger has a USB socket. Beware that a charger can supply the required current, and preferably more.
  14. (*steve*)

    Carbon monoxide sensor

    But given the sensitivity of the MQ9 to methane, you need to be sure you haven't eaten beans because your own methane emissions may swamp the CO level. Are you able to extrapolate the graphs? I thought something I read suggested that the MQ7 has a resistance which varies linearly with...
  15. (*steve*)

    Capacitor in parallel help

    If you connect two categories in parallel the total capacitance is the sum of the individual capacitances. The voltage rating is that of the lowest rated capacitor. As to which is "better", it depends on what you need the capacitor for.
  16. (*steve*)

    Passive low-pass filter

    Like crossover filters? ;-)
  17. (*steve*)

    Passive low-pass filter

    And it may be easier to place the filter before the amplifier, assuming the amplifier is for the subwoofer only.
  18. (*steve*)

    40 pin lcd to 50 pin controller board

    Are you certain that the display and the controller are compatible? Do you have the datasheets for both?
  19. (*steve*)

    Carbon monoxide sensor

    That's what the datasheet suggests. Have you read it?
  20. (*steve*)

    Carbon monoxide sensor

    MQ9 is also sensitive to other gases like methane
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