The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Monthly Science: Wearable LED vs. Dead CR2032 Lithium Cell

    Eight months later, the dead CR2032 cell driving the “ruby” wearable LED has dropped to 2.15 V:

    Wearable LED - on window
    Wearable LED – on window

    It’s not a true red LED with a 1.5-ish V forward drop, but a white / blue LED with red phosphor or a red filter, with a forward drop well over 3 V.

    Against the sunlit backdrop from our kitchen window, the LED looks dark:

    Wearable LED - daylight
    Wearable LED – daylight

    Seen in a dim room, it’s still glowing:

    Wearable LED - dim light
    Wearable LED – dim light

    The current is now far below the 1 mA/div of my Tek A6302 Hall effect probe, so I have no way to measure the few microamps lighting the junction.

    The coarse grid outside the window is a swatch of deer netting we put up during feeder season to keep the birds from killing themselves on the glass.