Search results

Search Forums New Posts
  1. (*steve*)

    Help With Circuit

    That's a lowecase m. Perhaps it is a 1 milliohm current sense resistor. However, that's a pretty low value resistor.
  2. (*steve*)

    Designing my first basic circuit - But have a few Questions

    I don't know. If the charger is smart enough to realise it is charging a low capacity battery and wind back its charge current then you may be ok. If the charger is one of the old fashioned barely regulated types then it may very quickly kill the battery. Post a link to both the battery and...
  3. (*steve*)

    Help With Circuit

    Why do you say upside down?
  4. (*steve*)

    HELP. transmit a wireless signal to

    So someone holds a button down for hours?
  5. (*steve*)

    Circuit Wanted To Buy...

    The original poster never came back. And is been 4 years.
  6. (*steve*)

    HELP. transmit a wireless signal to

    Ok. If a button press turns on the device, what turns it off? Is it another button press (of the same button) or something else? If you have a push once to turn on, push again to turn off situation, what happens if the system gets out of sync? I'd it a human pushing the button (who can push...
  7. (*steve*)

    Designing my first basic circuit - But have a few Questions

    Almost certainly. It's a possibility depending on how large the mismatch is and how dumb the charger is. No.
  8. (*steve*)

    HELP. transmit a wireless signal to

    So you want to send a stop signal when the switched 12V gets switched off? Can the switching on and off occur simultaneously (or within a very small period of time? E.g. Two 12V lines switched on within 10ms of each other, or one line being switched on simultaneously with another switching...
  9. (*steve*)

    Buck convertors

    I'm running short on time, but it's only 240W if the output is shorted. DONT SHORT THE OUTPUT Otherwise the power dissipated is I * (Vin - Vout) Even a TO-3 package can't dissipate much power without a heatsink! And transistors in parallel require additional work to ensure that the current...
  10. (*steve*)

    Help With Circuit

    Sorry, I was using my phone at the time and misread the 0V rail for 9V -- I assumed it was the positive rail. OK, so this is a current source which requires a negative voltage input. I'm going to have to go back and look at that circuit again. It looks like I've drawn the mosfet with the...
  11. (*steve*)

    HELP. transmit a wireless signal to

    Yeah, but that's not really relevant to whether or not you can place (say) a mosfet across the switch.
  12. (*steve*)

    Can't identify LED

    Ask the seller. Sometimes these types of LEDs can run off a straight 5V, other times they need a resistor. It may work placing three in series, but (in the case with flashing LEDs, for example) their current varies so much that they can be used to flash other LEDs in series with them.
  13. (*steve*)

    Boost converter 36 volts

    It's easier to have a voltage source higher than the led requires and then to build a constant current source. See our resource on LEDs for way more information.
  14. (*steve*)

    HELP. transmit a wireless signal to

    We lover amps here without resistors. But let's not talk about that. Do you have a constant 12V as well as the switched 12V? You would have to see how the buttons are wired in, but simulating a key press is way easier than building a multi channel transmitter and receiver. Is it possible for...
  15. (*steve*)

    Power supply help?

    That would probably be fine. Note that you have to do mains wiring to use this power supply. Not the best idea for a Newby.
  16. (*steve*)

    Power supply help?

    I'd recommend a 12v to 24v power supply rated at more than 3A
  17. (*steve*)

    Can't identify LED

    Here are some red/green color changing LEDs http://m.ebay.com.au/itm/100-pcs-5mm-red-and-green-alternately-flashing-LED-colour-changing-diode-au-/252406757728?nav=SEARCH
  18. (*steve*)

    Can't identify LED

    However, from the description, the OP is after color changing LEDs, not bicolour LEDs.
  19. (*steve*)

    I'm an electronics newb, and I need help with my first project (static grass applicator).

    The dc adapter is the plugpack (aka wall wart) The leftover piece needs to be redirected to the part you're using or nothing will happen. What voltage/current did the negative ion generator use, and what is your dc power supply rated for?
  20. (*steve*)

    OPA in mic preamp

    If there is any noise on the power rail, the reference voltage will move up and down. If both the feedback loop and the signal are referenced against this, the CMMR of the op amp will take care of the noise. In this case, the two have separate reference voltages. One will vary against the...
Top