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  1. (*steve*)

    Reverse Polarity Protection (some questions)

    The diode clamps the reverse voltage to about 1V until the heavy current causes the fuse to blow. After that, there is no reverse voltage. The failure mode for the diode is a short circuit, so the fuse will continue to blow and no voltage will reach the device until it is replaced.
  2. (*steve*)

    Partialy Discharging Capacitor

    Perhaps if you gave us a link to the original rather than your own interpretation we might be able to comment
  3. (*steve*)

    What are these symbols in a schematic.

    F is a double pole double throw switch.
  4. (*steve*)

    SMD 0805 capacitors

    Typically ESR measurements are only valid for capacitors above some value. Smaller value capacitors will show a voltage drop sure to the capacitor charging which exceeds that due to the ESR. When you read 95ohms, you are probably measuring a small value capacitor and not seeing the ESR. ESR...
  5. (*steve*)

    Reverse Polarity Protection (some questions)

    Place a diode from rail to rail after the fuse with anode to negative. If you connect the power around the wrong way, the diode will conduct and the fuse will blow. The diode may also fail (short circuit). Such a failure is safe because fuses will continue to blow until the diode is replaced...
  6. (*steve*)

    Replace Relay with TRIAC?

    Spurious high intensity transients When measuring the output under these circumstances with your scope, you may find "chaotic response at probe". If working on amplifiers, you may also get "frequently audible raucus tones".
  7. (*steve*)

    Voltage dropping in resistor

    I think I am just echoing what others have said, but for most purposes, the connections between components are considered to have zero length, zero resistance, etc. Practically they're not, but the difference is normally so small as to be inconsequential. For those of us with the appropriate...
  8. (*steve*)

    Reverse Polarity Protection (some questions)

    2 and 3 are equivalent. Neither require a heatsink for substantial loads with the correct mosfet. Large enough forward out reverse polarity will destroy the MOSFET though. Your next circuit (the one with the relay) could allow a brief pulse of reverse polarity to be applied to the load. This...
  9. (*steve*)

    Partialy Discharging Capacitor

    If it we're that simple everyone would do it. The circuit we've seen to control the flash duration is significant more complex, yours won't do it at all.
  10. (*steve*)

    Automatic switching between parallel and series connection

    At about the point that this simple analogy breaks down.
  11. (*steve*)

    Automatic switching between parallel and series connection

    In that analogy, voltage would be pressure, current would be the rate at which water is flowing, and resistance is the difficulty the water has flowing through the pipe. Resistance could be inversely related to the pipe diameter or roughness of the pipe or, well, resistance to flow...
  12. (*steve*)

    Automatic switching between parallel and series connection

    I've not used any of the energy harvesting chips, but I suspect that if you're getting the losses you observe then your doing something wrong. Can you provide a link to the datasheet for the energy harvesting board you have and for the chip and I'll do a bit of reading.
  13. (*steve*)

    2.4V Ni-Cd Charger

    I am now :) I wouldn't think so. NiCd chargers tend to either rely on the user to terminate the charge (typically with a 14 hour charge rate of C/10 or use rather more sophisticated circuitry to detect cell heating or a voltage dip.
  14. (*steve*)

    How do I run a dc motor slowly?

    If you're considering a stepper motor, there are a number of geared stepper motors. These are not geared so much that the stepper has to spin it's box off but it will make the rotation much smoother. Something like this might be suitable
  15. (*steve*)

    2.4V Ni-Cd Charger

    A resistor in series with D5 and another in series with D6 might help. When charging, NiCd's come up to voltage very quickly. The voltage is not a reliable measure of charge level. It's certainly not while the battery is being charged.
  16. (*steve*)

    Shmoo Plot

    Or it could be the dimensions of the array of data. For example 30 rows of 50 columns.
  17. (*steve*)

    Need help determining what pins go where

    The board send to have a very dark, near opaque solder mask making it very difficult to see where the tracks go. After following Dave's advice, try finding lighting that reveals the traces. Do you have the schematic (circuit diagram)?
  18. (*steve*)

    HP 54510A Power Supply Smelling

    Re-reading the thread to familiarize myself with the problem again... My understanding is that the SCR has been completely removed from the circuit, and that the power supply operates. The last image you posted showed 2 leads of the SCR unsoldered, but the remaining lead very close (shorting)...
  19. (*steve*)

    Trends Of Electronics

    If you know what each of these things are, you'll know which one is not a PhD research area.
  20. (*steve*)

    Consultation

    Ok. If you still have a problem then please redraw your circuit so it represents what you're now using.
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