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Not another Clock! Surely!

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I am keeping my head low with this post :) but I have been asked to design a clock, preferably using a blank CD as the face :D
Well the idea is this, one outer row of 60 Led's, assuming they will all fit, (THINKS- This is going to be a big CD), and an inner row of 12 Blue LED's to represent the hours. Each outer LED will be bi-colour such that for the first 15 seconds it glows Green, then for the next 15 seconds it glows Yellow, then the next 15 seconds Red. Finally for the last 15 seconds it flashes Green before changing over to the next LED. I suppose using common cathode LED's would make it a bit easier, with the Cathode selecting the actual LED to be lit. The Green and Red wires of each LED going to two circular Bus Bars that control the actual colour displayed. The hardest part it seems is getting 60 individual decodes, any ideas? A long string of 4017's errrr there must be an easier way?
I think it would be a cute clock if it is possible to build even though its accuracy is only down to the nearest 15 seconds. But a good conversation piece for visitors. Maybe someone has already made one?
Les
 
hi Les,
Consider breaking down the clock face into quadrants. [ or more sectors]
The same drive on/off's driving going to all 4 qudrants, with only one active quadrant enabled.

Do you follow OK.?
 
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Hi Eric, yes that sounds very very plausible. I must confess that the thought of running something like 74 wires to the clock face a bit too much to take :D

The ol' 4 to 16 line decoder might help here?
 
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Have a look at John Smout's web site: https://www.clock-it.net/
He has photos of several small circular led clocks.

For a CD sized one you may need to use surface mount leds.
If they were just single colour, you would only need an 8x8 matrix or use charlieplexing to reduce the microcontroller pin-count.
**broken link removed**

Using bi-colour leds adds a lot of complexity for such a small display, but it may be possible.
There are also several other designs, here are a few:
https://www.dos4ever.com/ledklok/ledklok.html
https://www.siliconchip.com.au/cms/A_104564/printArticle.html
 
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I am keeping my head low with this post :) but I have been asked to design a clock, preferably using a blank CD as the face :D
Well the idea is this, one outer row of 60 Led's, assuming they will all fit, (THINKS- This is going to be a big CD), and an inner row of 12 Blue LED's to represent the hours. Each outer LED will be bi-colour such that for the first 15 seconds it glows Green, then for the next 15 seconds it glows Yellow, then the next 15 seconds Red. Finally for the last 15 seconds it flashes Green before changing over to the next LED. I suppose using common cathode LED's would make it a bit easier, with the Cathode selecting the actual LED to be lit. The Green and Red wires of each LED going to two circular Bus Bars that control the actual colour displayed. The hardest part it seems is getting 60 individual decodes, any ideas? A long string of 4017's errrr there must be an easier way?
I think it would be a cute clock if it is possible to build even though its accuracy is only down to the nearest 15 seconds. But a good conversation piece for visitors. Maybe someone has already made one?
Les

Hi Les,

why not make it bigger? I made a "normal" analog clock using blades of a jet engine compressor. It's an eye catcher too. Sticking with the CD you might construct two circles, one for the hours around the CD and the bigger one around the blades to indicate minutes, enough space for duo-LEDs.

How to get compressor blades? Chase your chicken in front of a taking off jet. Get the blades free after engine overhaul. :D


Regards

Hans
 
Wow, some of those clocks are truly awesome. There is quite a lot of work on these type of clocks out there that I had not realised. Many thanks folks for the links and providing so much food for thought.
Les
 
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