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Photo & some advice on 3 of the shown components

Discussion in 'Datasheets, Manuals or Parts' started by KevinAlaska, Jun 12, 2007.

  1. KevinAlaska

    KevinAlaska New Member

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    Hello and thank you for reading my post first off. I have a photo link of a very small circut board that shows off a few components that I want to purchase but I am afraid to order anything because I lack the knowledge to make sure they are the correct components.

    I also need to find a good place to buy them if anyone knows of somewhere good. I probably only need like quantity 25 each of the 4 prime components on the board the other two are just resistors.

    Link is:
    http://farm2.static.flickr.com/1268/543321479_561182f163_o.jpg



    I have a question on first the capacitor. I think I found the following item and here is a link to a datasheep that seems like it. The text on the capacitor reads 474k and below that it reads 250V. I am also guessing that it is a capacitor. The link to the possible item's datasheet is next.

    Link is:
    http://www.alldatasheet.com/datasheet-pdf/pdf/179980/NTE/MLR474K250.html



    The second part is the little IC that has only 4 prongs coming off of it on to the circuit board. The following is the link that has a list of 7 items that could be all the same IC or all different. I was hoping someone could tell me. Here is the link to the possible IC's datasheet.

    Link is:
    http://www.alldatasheet.com/view.jsp?Searchword=DB107



    The last object is the LED. It is a rainbow LED which I know little about. The colors fade in and out kind of slowly maybe 1 color every 1 to 2 seconds. This is all of the main components that I can see besides the resistors and next which is the small electrolytic capacitor with 100micro farads and I think it listed 16v (is that 16 volts?).

    I love this circuit and I really want to make it over a few times if possible. I can't belive it is UL listed and runs so simply off of a standard US 120volts AC outlet.

    Well any help would be AWESOME. thanks again to everyone for the help.

    Sincerely,

    Kevin in Alaska
     
  2. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Kevin,
    The black component with 4 pins is a 'fullwave bridge rectifier' FWB.
    I would say 250Vac rated at 1amp.
    the '~' indicate the Vac input and the '+/-' the Vdc out.

    The red capacitor is a 0.47uF rated at 250Vac wkg.
    Using Xc=1/(2 * pi * 0.47uF * 60HZ) =5546R
    At 120Vac , Iamps= 120/5546= 0.021A, So across the 100R is approx 2.1V

    The resistor looks like a 100R.

    Cant help with the 'rainbow' LED.

    Important as there is no mains isolating transformer this pcb could be 'live', that is at mains potential, depending upon the mains connection.

    Where do you see the UL certification mark??
     
    Last edited: Jun 12, 2007
  3. KevinAlaska

    KevinAlaska New Member

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    Wow... great feedback... And thank you so much for it.
    The two wires just lead straight to a 120VAC us household style outlet. There is another small resistor on the bottom of the picture that read "brown, black, green, gold" so I thin that is 1,000,000R I believe? Seems high though. the lighting I had was yellowish and planned on checking that one closer before I did anthing.

    This mark is on the outside of the plastic housing of the unit that plugs in to the wall. Just RIGHT beside the plug on the Right hand side of the unit. This is just a little plug my son uses that lights up fiber optic like strands via the rainbow LED.

    Does the location of the UL mark mean anything? Why did you ask that?

    Sincerely,

    Kevin in Alaska

    PS... thanks again!
     
  4. dave

    Dave New Member

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  5. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Hi Kevin
    If the unit is sold enclosed in a 'sealed' plastic box, thats probably why it carrys the UL certification mark. [its safe] . Once you remove any plastic housing its no longer safe to use.

    It sounds like a 1M:eek:hm: resistor, it could be across the 0.47uF cap
     
  6. KevinAlaska

    KevinAlaska New Member

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    Yes it was sealed in a clear plastic (need a knife to open) package when I purchased it... only screw to actually open the housing up and 2 smaller screws to unmount the pcb off the inside of the housing.

    So last question is ... do you know of anywhere on the internet I can purchase some of these components and if so where? :)

    thanks a mill...

    Kevin in Alaska...

    PS... I have seen other posts of yours on here. You are very good at your answers. Can I like suck out the knowledge you possess in electronics... it would sure save me a heartache! :p

    Cheers!
     
  7. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Kevin,
    The components are very basic types that can be bought at most electronic suppliers.
    They are also fairly inexpensive, [cant say about the LED, insufficient info].
    Look in your local 'yellow pages' for your nearest stockists.
    [watch out for the shipping and insurance costs on web suppliers]

    I expect you are going to etch the pcb's yourself??

    Do you understand my concern regarding the lack of isolation.?
     
  8. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Kevin,
    This is a drawing of the circuit how I would expect it to be wired, check it thru and let me know what you find.

    The 10uF cap should be across the 100R.
     
    Last edited: Jul 7, 2008
  9. KevinAlaska

    KevinAlaska New Member

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    Well here is a layout of the circuit on that PCB. I have below a schematic of the componets for you. I hope it is easy enough to understand. I think I have some of the components drawn in the wrong direction but it should still be good to understand.

    [​IMG]

    Sincerely,

    Kevin in Alaska
     
  10. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi Kevin

    Redrawn, using your pcb track trace as reference.

    It looks as though they are pulsing the LED with fullwave rectified pulses via the 100uF cap.
    Its possible as the LED cycles thru different colours, there 'maybe' a counter in the LED, using the mains
    frequency.
    Reversed the LED.


    The 0.47uF is not polarised, it can be connected either way round, so have changed the symbol.

    EDIT: If you are wondering what the 1Mohm resistor, across the 0.47uF is for, look at 'fingers' thread "Meg ohm Resistors"
     
    Last edited: Jul 7, 2008
    • Like Like x 1
  11. KevinAlaska

    KevinAlaska New Member

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    Wow.. Awesome!

    I read that "Meg ohm Resistors" posting and it was easy to understand for a whelp like myself! Nice to learn something nifty as that one was. Does not sound like text book learning to me. Thank you for the advice of reading that. I like it when I can learn something that easy and that practical.

    So do you think this schematic is pretty much a done deal? Meaning, in your opinion do you feel it reads true? I can't wait to make a few of them.

    If it is good, then I am off like a wild herd of turtles to find a needle in a haystack... er... to find the much needed components on the internet. Any advice?

    :)

    I really REALLY appreciate it. I can not express how much you have helped me and you were AWESOME at it. Feel proud if you don't because you did your good deed for sure today! :)

    Sincerely,

    Kevin in Alaska
     
  12. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Let me know what type the rainbow LED is, if you can find out?

    Never had reason to use them myself, I'm sure other members can advise you.

    Dont worry about me helping out, just 'chill' out [thats a little alaskan joke].:D

    In the UK, we have a mental image of Alaska being super cool!

    Do they have herds of turtles in Alaska??;)
     
  13. KevinAlaska

    KevinAlaska New Member

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    is there a way of finding out on the LED? I can not see any images or printing. I can take it into the next room and inspect it further with much better light and maybe something to magnify it?

    Heh.. actually Alaska in the interior where I live (Fairbanks, AK) I have seen it reach 95F before. Nothing to where I used to live in Southern, California which hit 118F the summer before I left and moved here in the following December.

    But I have been to England 3 times each about a month long (Mostly in York). but I have toured all over from Lands End, to the top of a little past Edinburgh and from the west and east coast of England as well. I miss it and really want to take my family to visit there some day soon. They have never seen it.

    In the winters It has been as low as 56F below zero and I think the record is 66F below zero. FRICKEN COLD!

    Nope! No herds of turtles as of yet. But who knows. I might find the first. Just a saying a long ago friend in High School used to say that I adopted. Just a funny visual to me! ;)

    Cheers!
     
  14. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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  15. on1aag

    on1aag New Member

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    Hi Kevin,

    You better change the circuit a little bit, otherwise the 100 µF / 16 V
    capacitor will produce a hissing sound followed by a loud bang. :D

    on1aag.
     

    Attached Files:

  16. mneary

    mneary New Member

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    All of the parts you need are at Electronic Goldmine. It'll cost less than $3.50 on average to build them.
    G14518 bridge 3/$1
    G13897 blinking color LED $1.49
    G13213 capacitor $1.25
    G13646 capacitor 10/$1
    G433R resistor 100R 100/$3.50
    G516R resistor 1Meg 100/$3.50

    [edit] I'm tempted to use a smaller capacitor, G14508 8/$1, but because of its lower voltage rating I would add a fuse, G12999 4/$1, to protect me just in case. (315VDC should give me a safe capacitor at 120VAC.) [/edit]
     
    Last edited: Jun 14, 2007
  17. on1aag

    on1aag New Member

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    Hi Mneary,

    You better be careful, this circuit is meant for a continuous and
    constant current consumption, don't say I didn't warn you !
    Buy an extra bag of 100 µF / 16 V capacitors. :D

    on1aag.

    If you insist on using a blinking led you should connect a 1 Watt
    zener diode accross the capacitor's terminals like in this circuit.

    [​IMG]

    on1aag.
     
    Last edited: Jun 14, 2007
  18. mneary

    mneary New Member

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    That's a nice circuit, but it has nothing to do with this thread (driving one multicolor LED from a 120V 60Hz AC line).

    It's my understanding that the multicolor LED draws essentially the same current all of the time. In any case, 10uF should filter 21mA just fine.

    Why would we want an 'extra' bag of 100uF 16V capacitors? They don't appear in either schematic.
     
  19. on1aag

    on1aag New Member

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    Hi Mneary,

    You spoke of a BLINKING led, the current consumption will be
    approximately half of a normal led. This will cause the voltage accross
    the 100 µF capacitor to rise until it blows up. After that it's the blinking
    led's turn for it's final blink ! If you add the zener diode the excess
    current will flow through this zener diode and the voltage build-up
    accross the capacitor will be limited by the zener diode and nothing
    will blow up.
    I added the schematic of the 5 volt power supply to demonstrate
    that even a power supply with no load at all won't blow up if you add
    a zener diode.

    on1aag.
     
    Last edited: Jun 14, 2007
  20. KevinAlaska

    KevinAlaska New Member

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    Holly SMOKES! Thank you very much Mneary! I was looking for a place that I can buy components at and you did it for me thanks!

    How many of those blinking LEDs do you think that schematic I have just up a few postings can use before something is compramised? Any ideas?
     
  21. KevinAlaska

    KevinAlaska New Member

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    This project is already in existence. I was looking to figure out what was what on the PCB that I have in front of me. I can't imagine this would have any problems because its UL listed as is in its existing new package as you would buy it. Unless something is wrong in the listing. I reread the cap and it says on its side S.Y.(R), then 100uF then 16 v then finally 105C

    So what could be wrong with this then?

    sincerely,

    Kevin in Alaska
     

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