Made in China fail- LCD watch

Discussion in 'General Electronics Chat' started by takao21203, Nov 8, 2014.

  1. takao21203

    Thread Starter Distinguished Member

    Apr 28, 2012
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    Today I decided to open it instead of trying to get a refund.

    I found the problem quick- the foil connector wasnt glued correctly (or it has come off).
    No way to fix it.

    The tilt sensor seems to be a masterpiece of chinese engineering.

    Eventually I want to make a 7segment display from small LEDs which just fits behind the window, and use the PCB from a small USB charger to power it (via mains).

    I'll keep the thread updated, some time it can be moved to Projects/completed projects.
    Making the 7seg display isnt easy- there are no gaps between the LEDs. So far did 1 digit.

    Most likely I will use a serial display PCB, and a small 14pin PIC, maybe a RTC module too.

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  2. shteii01

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    The tilt sensor reminds me of Russian pencil vs American pen for the space program.
    ☺7
     
  3. takao21203

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    making a 7seg display! A regular 7seg display is far too thick, and only covers half of the area.

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  4. ErnieM

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    Apr 24, 2011
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    Heh... nice to see the insides. I got one like this last spring from Ikea.
     
  5. takao21203

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    Apr 28, 2012
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    update. The power supply fits into the battery compartment! The US plug can be attached to the backside too, there are two holes previously used for pushbuttons.

    The 7seg display will just fit into the display window.

    Inside the enclosure there is little space, probably have to put the refresh controller parallel to the 7seg display, and the clock PCB vertically.

    Maybe I would try to patch the power supply to 6 volts, and run it through PNP transistors to common anodes. I use 2x green LEDs in series each. Wiring the display is quite uncomfortable. A lot of work to do!

    I always wanted a clock that can be plugged in directly without a cable. And superbright emerald green too, not this green yellow french green.

    Cant use RTC module, there is not enough space, probably will use a 16f1503 running at 32 KHz directly. The serial display firmware is tolerant it can wait infinitely, clocking speed doesnt matter at all.

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  6. shteii01

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  7. takao21203

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  8. takao21203

    Thread Starter Distinguished Member

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    DSC02026.jpg

    This is how they look like, never saw a LED alarm clock with emerald green display (if you dont count VFD clocks which are not often found nowadays).

    DSC02037.jpg

    I will use one of these 16F54 PCBs for the display.
    In theory it is possible to integrate the clock program too, but it needs a 32 KHz crystal and the refresh will be slow, or complicate algorithm for other crystals.
     
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  9. takao21203

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    7segment DIY...

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  10. ISB123

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    May 21, 2014
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    Looks like fun project,in what kind of package are those leds?
     
  11. takao21203

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    they must be 3x2x1 or something like that.

    And very bright.
     
  12. AnalogKid

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    Aug 1, 2013
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    I know that story. It's great, except the part where none of it is true.

    ak
     
  13. shteii01

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    "Never let facts get in the way of good story."
     
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