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  • Digital clock with seven segments display flickering

    From wu.ming2@icloud.com@21:1/5 to All on Wed Dec 11 04:24:51 2024
    My no brand digital clock is beginning to flicker. Numbers are the
    illuminated kind, 7 segments display and not LCD. Powered through USB
    cable.

    I have been using it for about five years. Most evenings I switched it to
    the touch sensor so display is actually off for the night. Trying to extend
    the display lifetime.

    There’s anything I can do to fix it? Thanks for sharing.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Miguel Gimenez@21:1/5 to All on Wed Dec 11 11:06:34 2024
    El 11/12/2024 a las 5:24, Wu Ming escribió:
    My no brand digital clock is beginning to flicker. Numbers are the illuminated kind, 7 segments display and not LCD. Powered through USB
    cable.

    I have been using it for about five years. Most evenings I switched it to
    the touch sensor so display is actually off for the night. Trying to extend the display lifetime.

    There’s anything I can do to fix it? Thanks for sharing.

    A dying LED does not flicker, just looses brightness (white lighting
    LEDs do blink, but that is a thermal problem with chinese crap).

    The power supply (external or internal) may be oscillating; Change the
    external supply or look for dry capacitors in the internal one (if any).

    --
    Saludos
    Miguel Gimenez

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Richard Jones@21:1/5 to Wu Ming on Wed Dec 11 11:32:35 2024
    On 11/12/2024 04:24, Wu Ming wrote:
    My no brand digital clock is beginning to flicker. Numbers are the illuminated kind, 7 segments display and not LCD. Powered through USB
    cable.

    I have been using it for about five years. Most evenings I switched it to
    the touch sensor so display is actually off for the night. Trying to extend the display lifetime.

    There’s anything I can do to fix it? Thanks for sharing.

    Could be a fault appearing in the mux circuitry. In most such displays
    all the same position segments are connected together and each number
    selected one at a time in turn. When done fast enough the human eye
    doesn't notice the chasing.
    Mind you that's probably all done within the main clock IC so not much
    else to go wrong. Any chance of getting the clock open and posting the
    main IC device number?

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From wu.ming2@icloud.com@21:1/5 to Miguel Gimenez on Wed Dec 11 11:22:11 2024
    Miguel Gimenez <me@privacy.net> wrote:
    El 11/12/2024 a las 5:24, Wu Ming escribió:


    A dying LED does not flicker, just looses brightness (white lighting
    LEDs do blink, but that is a thermal problem with chinese crap).

    Actually they are white. Flickering is currently faint but perceivable
    already.


    The power supply (external or internal) may be oscillating; Change the external supply or look for dry capacitors in the internal one (if any).


    Will switch to batteries first and see if it changes anything. Thanks for
    the suggestion.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From wu.ming2@icloud.com@21:1/5 to Miguel Gimenez on Fri Dec 13 23:46:34 2024
    Miguel Gimenez <me@privacy.net> wrote:
    The power supply (external or internal) may be oscillating; Change the external supply or look for dry capacitors in the internal one (if any).


    It is the USB power supply oscillating. Switched from a HuntKey one, brand
    I have never heard of and can not remember the bundle it came with, to an
    Apple one and is now rock solid. I need the Apple supply though: it is
    possible to fix the oscillating one? Thanks.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From wu.ming2@icloud.com@21:1/5 to Richard Jones on Fri Dec 13 23:50:08 2024
    Richard Jones <news@rgjones.screaming.net> wrote:
    Could be a fault appearing in the mux circuitry. In most such displays
    all the same position segments are connected together and each number selected one at a time in turn. When done fast enough the human eye
    doesn't notice the chasing.
    Mind you that's probably all done within the main clock IC so not much
    else to go wrong. Any chance of getting the clock open and posting the
    main IC device number?


    Interesting. It was not necessary to disassemble and I doubt would have
    been possible. Don’t see screws so likely is glued together.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Miguel Gimenez@21:1/5 to All on Mon Dec 16 11:48:31 2024
    El 14/12/2024 a las 0:46, Wu Ming escribió:
    Miguel Gimenez <me@privacy.net> wrote:
    The power supply (external or internal) may be oscillating; Change the
    external supply or look for dry capacitors in the internal one (if any).


    It is the USB power supply oscillating. Switched from a HuntKey one, brand
    I have never heard of and can not remember the bundle it came with, to an Apple one and is now rock solid. I need the Apple supply though: it is possible to fix the oscillating one? Thanks.

    Yes, replace the electroytic capacitors; Usually there is one in the
    high voltage side and other in the low one, start with the latter.

    --
    Saludos
    Miguel Gimenez

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)