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  1. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    The emitter resistors should not need to drop a large voltage, and thus should not dissipate so much heat that a heatsinked resistor is needed. If you add base resistors, balancing will be even better. Yes I'm also surprised the resistors were not isolated from their case, but this is...
  2. (*steve*)

    Getting into hot water

    Arriving at the office today I saw the following: And I noticed a circuit board had been pulled out. Hmmm, something is going on... Some subtle clues on the top side: And some evidence of poor design and Hodges to fix it: It looks to me that there is/was a high resistance...
  3. (*steve*)

    Component used to measure weight?

    sorry, what you want is a load cell (which is a form of strain gauge designed for measuring weight, ebay have them
  4. (*steve*)

    Pokemon Go

    I can't imagine they'd mind too much.
  5. (*steve*)

    Mini USB on camera PCB came loose

    It looks like the usb socket has been ripped from the board taking the solder pads with it. This is a very difficult repair.
  6. (*steve*)

    Standard method to prevent over discharge of Li-po 3.7V battries

    A protection circuit. (google "lipo protection circuit")
  7. (*steve*)

    Component used to measure weight?

    You would be unlikely to build anything smaller than a small commercial scale. What you are probably looking for is a strain gauge. The electronics to convert the small signal to a voltage are not trivial.
  8. (*steve*)

    Measure very low valued photoresistor

    So do you just want to measure its resistance, or use it to measure illuminance?
  9. (*steve*)

    Vending Machine GUI

    C, assembler, C++, python, basic, forth, Cobol, Fortran, algol, Pascal, apl, pl/1, c#, f#, PHP, Java, JavaScript, ruby on rails, Haskell, ada, Modula 2, lisp, prolog, bash, bcpl, SQL, cold fusion, clipper, dbase, Delphi, Eiffel, Legoscript, logo, perl, R, Smalltalk, teco, or any one of many...
  10. (*steve*)

    wheelchair joystick

    I guess the answer is no :( Do you know anyone with one you can borrow?
  11. (*steve*)

    wheelchair joystick

    Without technical documentation it is impossible to say. Do you have the technical specs of the interface?
  12. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    Having parsed the original circuit (and my brain hurts) it appears to be topologically similar to mine above with the exception of base resistors (R3) which are not strictly necessary and the change in the feedback loop position. @heavyfletch2nd, if you need help with your circuit, people can...
  13. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    I have wondered why this isn't an option for variable regulators? You could parallel the transistor and its associated resistors at the red points as far as you see fit. You would probably want a resistor from pin 2 of the 317 to ground as well. (and the capacitor values would need revision)...
  14. (*steve*)

    Pokemon Go

    With the amount of free time I have, I'm somewhat glad my phone doesn't support it.
  15. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    On a circuit diagram the components are shown in a way which makes the function of the circuit clear. Part of this involves following certain conventions, one of these being that in general inputs are shown in the left and outputs on the right. The actual physical placement of the pins is...
  16. (*steve*)

    Fuses, fuses...

    If you have the old fuse, it should have some markings which indicate the speed (other things are listed but you already know them). If unspecified, use a "fast" fuse. These are the typical fuses you find. The other common type is slow -- they generally have some sort of spring inside them.
  17. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    Where did you get that circuit from? I think you'll find the correct circuit in the LM317 datasheet.
  18. (*steve*)

    Which chip used to optimize measuring many batteries.ject

    You may want to pass the resulting waveform into a peak hold circuit. The voltage read here will not be the battery voltage. You will need to determine a calibration curve to convert the peak voltage to a battery voltage
  19. (*steve*)

    Ultra Bright LED Dimmer with a sliding potentiometer

    24V is too high for a 555 from memory. But if you're asking if you power the 555 circuit and it powers the LED, then yes.
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