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  1. F

    timer to trigger latch

    like i said, it's silly
  2. F

    timer to trigger latch

    alright... the intent of my device, though it sounds silly,  is this: http://www.canadiantire.ca/AST/browse/6/Tools/WeldingSoldering/AccessoriesRodsWire/PRD~0580037P/Lincoln%252BElectric%252BAutodark%252BFlame%252BThemed%252BWelding%252BHelmet.jsp?locale=en i can't cough up that much for some...
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    timer to trigger latch

    it wasn't a competition. i wouldn't have come here if i knew the answer. other than that, i have a question about latching push button switches... do they usually go back to being open after the power through them has been cut-off?
  4. F

    timer to trigger latch

    the "high capacitance capacitor", above, when shorted, is what supplies the power for my external electromagnetic coil; snapping a hinged mechanism. i know i sounded non-sensical. i tend to do that every once in a while.  ;D
  5. F

    timer to trigger latch

    cool. it's just that i really don't have a clear grasp of the theory. so, you'd have to explain to me why and how much better this one works. although i think you forgot that i wanted to start the timer after i pressed a second button.
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    timer to trigger latch

    cool. so it works glitch-free, then, huh? and after the whole cycle (after it shorts the control and turns itself off), the whole circuit absolutely doesn't draw any more power, right? btw, is there any way to lower the voltage to just about 3-5V?? i'm thinking of only using rechargeable...
  7. F

    timer to trigger latch

    btw does this: draw power even when switch has not been pressed yet?
  8. F

    timer to trigger latch

    this is my mod... i'm thinking C1 = ~70uF and C2 = 10 uF.... would it work?? of course, the TIP32 (<- 1st time i've seen a transistor like that, really) on the top would still be drawing power. and to avoid that, i'd have to replace that section with the latching relay again and that...
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    timer to trigger latch

    i'll edit and combine the 1st and 3rd circuits so to point out what i meant -- i could be wrong, of course. but i'm basing this on my assumption that the 3rd circuit cuts off the output supply after the button is pressed. i haven't picked which schematic editor and/or SPICE simulator to use...
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    timer to trigger latch

    well i pretty much get the GIST of the above diagrams. and really can't do the calculation or math, but i can see that when assembled together as a control circuit (i guess i'll pick the PNP version??).... i can use a dpst switch for both circuits... press it... 1, 2, 3... turns on the...
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    timer to trigger latch

    @hotwater: call me silly, but i take it that my mod works, just that there are no "non-debouncing" button out there so i have to build it out of another 555?.... pfffttt... then the circuit just got bigger. had to be small. ok.... if there are other packages out there that does what i asked...
  12. F

    timer to trigger latch

    will MY mod produce the functionality that i outlined above? if so then i need to know parts numbers for the relays and non-debouncing push button, if it even exists. the s1 latching button should ideally re-open when power is cut-off. a bit idiotic to ask, but is it even possible for this to...
  13. F

    timer to trigger latch

    ok, i guess there's no harm in stating the full functionality of the device... (i didn't say so as it seemed silly) press push button 1 and it switches the time delay control circuit on. for practical purposes, the high capacitance capacitor for the electromagnet will always be in parallel (ON)...
  14. F

    timer to trigger latch

    http://www.electronics-lab.com/forum/index.php?topic=22577.0 the above is just the rough sketch.... ok, i guess there's no harm in stating the full functionality of the device... (i didn't say so as it seemed silly) ok. press push button 1 and it switches the time delay control circuit on...
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    timer to trigger latch

    what specific part do i need if want a solid state relay that is normally open, dpst, and is operated by a current that has a very large gap to switch on or off... (by the last requirement, i mean if the normal off current is 0, the on has to be 100mA... or 10mA - 1 A. or something like that.)...
  16. F

    timer to trigger latch

    ok, if i get the explanation on the main page correctly i want to base the trigger on this circuit: http://home.cogeco.ca/~rpaisley4/LM555Delays1.GIF (i'm referring to circuit #1, ignore #2) what's the cheapest way to rig  this so that it will short a high capacitance capacitor (about ~30 mf...
  17. F

    timer to trigger latch

    i am using a coil. it's just that the core will be made from electrical steel. those small transformers are made out of sheets of electrical steel, right? i'll just cut them up and stack them together again to get a bar as a core
  18. F

    timer to trigger latch

    figure i'd be making the core from electrical steel bar about 2.5 cm x 0.3cm x 0.3cm (salvaging from strips off a small transformer)... something like that. has to be small and light. basically press the toggle switch... 1, 2, 3.... hinged mechanism snaps close.
  19. F

    timer to trigger latch

    i need to have a really small timer circuit that would trigger the closing of a hinged mechanism. not much, but i want it snap shut really fast. so i was thinking of using a simple electromagnet that would pull back the hinge. the timer has to be small and can be very crude. i'm not asking...
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