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  1. (*steve*)

    100 milisecond delay circuite

    There is only a single capacitor
  2. (*steve*)

    Blowing fuses on 1980's Fisher CA-880

    Ok Travis, all we need now are some good photos. See here
  3. (*steve*)

    Current sensing circuit help

    You need values which will give you the same voltage the acs712 gives you when it has zero current through it. I don't know how you're powering it, it what it's rails are referenced to, so that bit is up to you. If you connect the voltage divider up to the power supply for the acs712, you...
  4. (*steve*)

    Current sensing circuit help

    No, I'm referring to R3 and R7 in my circuit in post #23
  5. (*steve*)

    Jazzmaster style bullet strat guitar cavity

    No. Is there a question in there? If that's the question, then I'd say "after the preamp".
  6. (*steve*)

    Square wave to DC level

    Is the input high, low, or indeterminate when the input signal is absent? How long from the first edge do you need to know that the signal has returned? How long after the last edge do you need to know that the signal has stopped? Assuming the answers are something like low, about 10ms, about...
  7. (*steve*)

    100 milisecond delay circuite

    What do you want to delay? A fairly simple solution would be something like this: With the appropriate choice of R and C, this will delay both rising and falling edges of a logic signal. However, as the edges get closer together, the delay will decrease, and at some point the output will no...
  8. (*steve*)

    Current sensing circuit help

    Yes, but you need to change the resistor RS so that the adjustment range is a few millivolts either side of the expected "zero current" output voltage of the ACS712
  9. (*steve*)

    Phone's car charger

    I don't know, that's why I suggested that replacing the IC wouldn't hurt.
  10. (*steve*)

    MOSFET burning up but similar circuit on another board is fine

    I would be interested in a few measurements and/or details. What is the voltage across the MOSFET when it is turned on (and in the process of "burning up". I would attach a heatsink to the MOSFET for this test. Is the solenoid actuating? What is the actual Vgs when the MOSFET is turned on (no...
  11. (*steve*)

    MOSFET burning up but similar circuit on another board is fine

    Since we now know where they came from, it may be time to get off this particular high horse for a while.
  12. (*steve*)

    Phone's car charger

    I wouldn't have thought that the fault is highly indicative of a failure of the IC, but if you have another one and you can replace it, there's not much to lose.
  13. (*steve*)

    Current sensing circuit help

    I would stick with the 1:100, and place three turns off work through it (or as many as you can). Make sure you fix the offset circuit. Also, look for millivolt level output. And the core doesn't need to saturate for the current transformer to operate. In fact, when it does saturate, you have...
  14. (*steve*)

    How much power needs to light up the LEDs?

    They may start to light up at about 3 volts and get brighter and brighter as the voltage increases.
  15. (*steve*)

    How much power needs to light up the LEDs?

    One thing you can tell by looking is that there must be 7 strings of 2 LEDs. That means the voltage you need to apply is at least twice the voltage each individual LED requires. The series resistor in each string acts to limit the current at a particular applied voltage. Because these are not...
  16. (*steve*)

    How much power needs to light up the LEDs?

    Read this. It contains a lot of information about LEDs. You don't need much power, but you need to apply it correctly.
  17. (*steve*)

    Wireless power transfer

    Crystal radios (and their modern equivalent, the RFID tag) are not exactly new tech. The problem is what you can do with a small amount of power, or conversely, how you can get an appreciable amount of power wirelessly.
  18. (*steve*)

    Current sensing circuit help

    The precision rectifier you have is better because the op amp is always operating in closed loop conditions. The protection they use of a pair of back to back zeners is functionally similar to the two diodes you are using (the expected voltages are low enough that it doesn't matter). The...
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