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Basic problem with transistors

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by giftiger_wunsch, Jul 25, 2009.

  1. giftiger_wunsch

    giftiger_wunsch New Member

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    Yeah I noticed you said coping saw twice. And once with a typo :p


    Though the IDC header looks useful, there are two problems:

    1) As I mentioned before, I'll want one- or two-pin sockets for the cable-mounted sockets

    2) The physical lack of space around where the header is going to be situated means that the boxing around the connectors will prevent it being mounted on the board. Give me a second and I'll provide a photo to show you what I mean. There's very little clearance around the parallel terminals, barely even room for the PCB interconnect headers I linked to before.
     
    Last edited: Aug 13, 2009
  2. Hero999

    Hero999 Banned

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    Did you checkout the components I linked to?
     
  3. giftiger_wunsch

    giftiger_wunsch New Member

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    I did; see the edited post :)
     
  4. dave

    Dave New Member

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  5. Hero999

    Hero999 Banned

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    So I take it you're going to be using one 26pin header and connecting loads of little two pin cable sockets to it?

    I'll have a look for two pin IDC cable mounted sockets.

    EDIT:
    Short of buying a Molex connector which would also require you to buy 500 or so crimp sockets for £7.90. You could use a PCB mount connector soldered on the end of a piece of cable. It's a bit of a bodge but it'll work. I strongly advise covering the exposed sholder connections with heatshrink sleeving.

    http://www.rapidonline.com/producti...nnect&tier4=Single+row+sockets&moduleno=76075
     
    Last edited: Aug 13, 2009
  6. giftiger_wunsch

    giftiger_wunsch New Member

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    Indeed. Or even single-pin sockets if possible.

    [NOOBQUESTION]By the way, what exactly is IDC? Looking at the connectors, it seems to be more or less the same as the headers I was looking at, except it had a plastic frame around the pins. They seem familiar as well... used to be used in computers to connect hard drives etc. I believe...?[/NOOBQUESTION]

    Either way, the 36-pin single-row headers I found are cheap and look useful, so really it's just a matter of finding 1- and/or 2-way wire-mounted sockets suitable for use with them.


    By the way, here's the photo as promised. Sorry for the large size, that was *after* cropping it down and then setting the image size to 40%. I love my camera :D

    [​IMG]


    For an idea of scale, the holes are 1mm wide and 2.52mm (ish) apart, and the module you see mounted above the board is approximately 8mm above the board.
     
    Last edited: Aug 13, 2009
  7. Hero999

    Hero999 Banned

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    IDC connectors are just connectors with the pins arranged in a 2.54mm, 2mm or 1.25mm matrix. The headers will mate with ICD connectors.

    See my edit to my previous post for a two pin socket suggestion.
     
  8. giftiger_wunsch

    giftiger_wunsch New Member

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    I was considering that but that seems... complicated. It's surprising rapid don't sell such a common part. Is it worth me asking what a molex connector is by the way? :eek:
     
  9. thepaan

    thepaan Member

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    Molex is a 4 pin power connector providing +12V and +5V that once was the standard connector for nearly everything inside a PC. SATA drives have a new connector (both optical and disk drives) and video cards and motherboards both have different connectors now as well.
     
  10. giftiger_wunsch

    giftiger_wunsch New Member

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    If that's all it really is, I think I'll probably just stick to the 2 x 34-pin headers and cut them down to 25 pins each. All I need now is a tonne of 1- and 2-way wire-mounted sockets. Unfortunately the closest I can find are jumper links, which are no good to me :(
     
    Last edited: Aug 14, 2009
  11. giftiger_wunsch

    giftiger_wunsch New Member

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    I sent a query to rapid, and it seems I'll have to make do with the 2-way variety of these. I'll have to simply solder the wires onto the pins and trim the pins down. Unfortunately these are nearly 8x the price of the 2-way header plugs.
     
    Last edited: Aug 14, 2009
  12. Hero999

    Hero999 Banned

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  13. giftiger_wunsch

    giftiger_wunsch New Member

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    The 2-way housings are £4.50 for 50 and 100 crimp terminals are £3.95, so it shouldn't be too bad... that'll last me a while. The headers are shorter and more expensive and have a raised piece of plastic on one side which may get in the way, but if the pin sizes are the same the housings should be compatible with the cheaper headers I linked to earlier.

    The pins on the headers linked to earlier were 0.64mm square, but the data sheet for the molex headers doesn't seem to indicate the actual pin dimensions...
     
  14. Hero999

    Hero999 Banned

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    I forgot to mention that ideally you'll need an expensive special crimping tool but you might be able to get away with using pliers.
     
  15. giftiger_wunsch

    giftiger_wunsch New Member

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    I hope so :D the contact just needs to be pressed together to bend the incomplete circle of metal around and hold the wire in place right? Sorry, crimping is another thing I haven't yet had to do. A sturdy pair of pliers should do the job, I hope.
     
  16. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    You can solder them quite easily, and in the absence of the proper crimping tool is probably the best method - use pliers to close the cable restraint over the insulation.
     
  17. giftiger_wunsch

    giftiger_wunsch New Member

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    That should do fine then. Only remaining problem is that the raised plastic portion of the molex header is likely to get in the way, and that they don't sell any larger than 12-way. If possible I would like to use the molex housings + crimp terminals to plug into the cheap headers I was already planning on purchasing, but unless I can be sure that the molex housings will fit over the pins, that may be a bad idea :( if molex is a standard, perhaps I could find a better data sheet, which gives the dimensions of the pins themselves?
     
  18. Hero999

    Hero999 Banned

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    Please post a link to them.
    Yes you can solder them but I would have never got away with that at work.:D
     
  19. giftiger_wunsch

    giftiger_wunsch New Member

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    Rapid Electronics - Cables & Connectors

    It's just the first link in your post. Note that the 100-packs of crimp terminals are at the bottom of the page.

    Good thing it's a hobby project; I'm my own boss :p if I catch myself soldering it I'll just have to give myself a stern talking-to.
     
    Last edited: Aug 14, 2009
  20. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Why not?, it's certainly better than not using the correct tool, and probably actually better than using the correct crimping tool.

    Or are you talking about the time involved?, crimping is far faster than soldering, which is why it's used.
     
  21. giftiger_wunsch

    giftiger_wunsch New Member

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    Indeed I did mentally groan at the mention of soldering every contact on, but hey it's good practice and I certainly need it :D
     

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