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LED replacement

A project log for Heroineclock II

Giant clock from a PIC18F6585, 135 cheap LEDs, foam core posterboard, hot glue, lots of hot glue

lion mclionheadlion mclionhead 07/07/2018 at 06:360 Comments

It was 1st documented in Nov 2017 that a segment had died, as they always do.  Lions wait as long as possible, in case more segments quickly followed.

8 months later, all 5 LEDs had to be replaced.  The lion only ordered 5 replacements.  The next bad segment will require using higher voltage ones with the higher voltage regulator or another $20 digikey order of yet another voltage.  Not easy to have any surplus, since China only does 1 run of each LED design.

Also replaced the backup battery with a 45000uF cap.  It feeds the regulator's feedback resistors, so it only lasts a second.  It's good enough for glitches & there's nothing to configure on the clock.  The backup battery was worthless, since the power went out often, for over 4 hours & a charging circuit would have been expensive.  Without a charger, it was easier just to reset the time than disassemble it.

During the year without the segment, telling time was still possible.  It made the lion kingdom wonder, with all the funky binary, octal, hex, flipper clocks, what is the minimum number of segments required for the minimum useful precision?  It's 11 segments, 5 bits for the hour in binary, 6 bits for the minutes in binary.  You'd have to be a savant to decipher it, or a candidate for a SpaceX job.  

Binary coded binary is still too hard.  Hex hours with base 10 minutes would allow dropping 2 hour segments & still be easy.  It might be hard to remember the minutes were base 10.

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