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  1. (*steve*)

    LM358n issue

    We can't do anything until you show us your circuit.
  2. (*steve*)

    Counterfeit IC's

    The more worrying thing is the re-labelling of parts by the manufacturer. Sure it seems to be to label (if I read it right) high spec parts as lower spec, but it really muddies the water.
  3. (*steve*)

    Circuit Issue Help

    Do you have a series resistor with that LED?
  4. (*steve*)

    LM358n issue

    33 Amps? From an op-amp? You've got to be kidding. Tell us what you are actually trying to do, not how you think it can be done.
  5. (*steve*)

    LM358n issue

    The answer to the problem is becoming clear...
  6. (*steve*)

    Decade Counter

    Do any LEDs light? A problem that you will have is that a single press of the button may cause the counter to count anything from a few to dozens of pulses as keybounce from the button causes lots of transitions. Also, you need to pull the input to a definite voltage level via a resistor...
  7. (*steve*)

    Question on LM317 based high current voltage regulator

    You don't show where the output is. I presume it is across the 1K resistor?
  8. (*steve*)

    Decade Counter

    Do you have a circuit diagram? Presumably that's a 4017? What is your power supply and which of the wires are positive and negative?
  9. (*steve*)

    Transistor

    I'm really not sure what you want to do now. What is your source of 0-5V? What do you want to do with the 0-18V? it's not generally possible to get an output higher than your supply voltage. And as I said, some op-amps can operate from a single ended power supply (+ve only) but there may be...
  10. (*steve*)

    Transistor

    So you want to convert a signal that varies between 0 and 5V to a voltage which varies from 0 to 16V? What external power supply do you have available (it will have to exceed 16V)?. A +/- 18V supply would be ideal, but it doesn't have to be symmetrical -- +18V/-2V would probably work just as...
  11. (*steve*)

    Unidentified Circuit

    Maybe this that know can't say? :) I doubt you can actually tell what it was from the photos, however there has been some perfectly reasonable suggestions as to the type of equipment it could have come from. Think high reliability, high vibration environment, zero maintenance once deployed...
  12. (*steve*)

    Identify smd capacitor

    Unfortunately that schematic fails to list most of the part numbers.
  13. (*steve*)

    Finding suitable portable LED light replacement IC charge regulator

    My first choice would be to try to find one of these chips. What is your train for suspecting this chip?
  14. (*steve*)

    Submerging a CoB LED

    60W of LED lighting is probably the equivalent of the or four 100W bulbs. The first question is whether you need that much light.
  15. (*steve*)

    MOSFET getting hot and making noise

    In light of it now functioning, no. The voltage regulation really only works by accident. If it's working, don't mess with it. I suspect that with a better design the quiescent current would be closer to 20mA than the 40mA it is now, but that's not a huge difference. I suspect that what...
  16. (*steve*)

    MOSFET getting hot and making noise

    The main problem is that the voltage control doesn't work right. It controls the frequency rather than the duty cycle. As a simple mod, I would disconnect the stuff connected to pins 4 and 5, then connect what was connected to pin 5 to pin 4. This will pull the 555 into reset as the voltage...
  17. (*steve*)

    Simple digital clock

    Use a higher value pull-down. 10k should be fine.
  18. (*steve*)

    Kustom organ repair of funky contacts

    A picture would help, but presumably these switches were made to a price (cheap). You may be able to replace them with a lever operated microswitch or similar.
  19. (*steve*)

    High voltage: Can't stop electricity from jumping over resistors

    If using standard resistors, a max of between 200 and 500 volts each would be a reasonable guideline. So instead of using 6 x 100k resistors, use something like 100 x 6.8k resistors.
  20. (*steve*)

    For Sale: Heathkit original manuals - pristine

    $3 flat rate to Australia, cool! :-D
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