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  1. (*steve*)

    Off grid and popping capacitors on electronics

    If the title of this thread has any meaning, then buying 1000 replacements will not solve your problem. If these devices are failing it is likely because your voltage is too high or the are high energy voltage spikes.
  2. (*steve*)

    Hey, anyone want something they can take into space?

    The most special thing about them is the labeling. I expect there was once a paper trail which could be used to prove they meet the specifications and allow them to be traced back to the manufacturers batch. I assume it's not unlike medical device QA stuff.
  3. (*steve*)

    Transistor pair to switch between Voltages

    To keep it simple, you must use a P channel MOSFET and an additional transistor to do level switching.
  4. (*steve*)

    I want to design using by cascading 74*163 ic

    First you need to understand how to cascade the devices so you can count to a higher number than 15. Then you need to understand how to load a number into them. Then you need to work out the logic to decide if you have reached a certain maximum count. You might want to look for an 8 bit...
  5. (*steve*)

    I want to design using by cascading 74*163 ic

    I'm sorry,. I can't understand what you want.
  6. (*steve*)

    I want to design using by cascading 74*163 ic

    I think you want this.
  7. (*steve*)

    Woo Hoo HP5316A

    For those playing along at home, the GPS receiver is an HP Z3805A. Oh, and the two clock signals look so nice together on a scope. :-) Next step is to compare the GPS signal to my rubidium frequency standard (but not this weekend)
  8. (*steve*)

    Woo Hoo HP5316A

    I've spent some time getting my HP5316A and HP5334B working. (They are both 2 channel counters AKA frequency meters). I am using my GPS 10MHz signal source as a reference. With a bit of tweaking the HP6316A's clock can be adjusted to within a few tenths of a Hz from the GPS, but it drifts a...
  9. (*steve*)

    Current control and defence

    Where does that circuit come from? As far as I can tell it's badly wrong, but if you can point me to a source I may be able to make more sense of it.
  10. (*steve*)

    Current control and defence

    What you are saying is wrong in too many ways to easily set you straight. What sort of battery is it? Is it a lead acid battery? If so, what capacity? SLA? What power source do you have?
  11. (*steve*)

    Current control and defence

    Why do you want to short the battery? All that will do is discharge the battery.
  12. (*steve*)

    Hey, anyone want something they can take into space?

    Check this out.
  13. (*steve*)

    More woes driving LEDs via PWM

    What voltage do you get with the rpi outputs? is it 3.3V? What current are you switching? Have you tied the rpi ground to the source of the mosfets? Have you looked at what is happening at the rpi output with an oscilloscope (or even measured it with a multimeter)?
  14. (*steve*)

    More woes driving LEDs via PWM

    Definitely gate to source (what was I thinking!). Do the mosfets heat up when the gate resistors are fitted, but no connection is made to the Arduino? (they shouldn't) Are you certain you set the pins to be outputs and pull them low as part of the arduino initialization code? Do you know the...
  15. (*steve*)

    Current control and defence

    The input may be pulsed DC. SCRs have been used as regulating elements. Given what seems to be a major design fault whether I'm not going to try to figure out what's up with this part of the circuit.
  16. (*steve*)

    More woes driving LEDs via PWM

    Well, they are necessary if what is connected to them is floating. It sounds like the OP did not have them set as outputs at some point.
  17. (*steve*)

    Current control and defence

    Presumably the TIP142 is there to act as a smoke generator? From the look of this circuit it shorts out the battery.
  18. (*steve*)

    More woes driving LEDs via PWM

    Add a resistor between gate and SOURCE of each MOSFET. A value between 1k and 10k should be fine. edit: I said drain (aaaagh)
  19. (*steve*)

    Step Down DC Buck Capacitor Blow up

    My guess is that the battery voltage is higher than the nominal 48V. My guess is that fully charged it would be a little higher than 50V (assuming 12 cells in series). So there's the source of the 50V that was read at the output -- the board didn't need to act like a boost converter. if the...
  20. (*steve*)

    Oscilloscope

    You might want to view this. He spends all of a few minutes on scopes, but it's worth a look at. Compare the price with an analog scope. Sure, I still have an analog scope (several actually) but you need to balance age, price, and reliability.
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