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Custom 8 digit Alpha Clock help.


Sorry if this is the wrong section.

I've been thinking about making an 8 digit Alpha Clock. I'd like to start out with the Alpha Clock Five kit, and order three more displays, but it seems like the displays are pre-attached to a board, as I'd need them separate for the particular project I want to work on. 

Are the displays already attached onto the board, or can they easily be separable? If already attached, is there a part list I could follow to order the individual parts, just like the kit, just with three more displays and anymore splitters/boards I'd need (or anything else for that matter)? 

Thank you! 


  • The displays are socketed, and can be removed with some careful wiggling. Our store does also sell the displays separately, so there's no issue there.

    The displays are a bit challenging to drive, since the different segments take different voltages and currents, and the Alpha Clock Five multiplexes the displays to spread the cost of the drivers amongst five displays. You could in principle extend the multiplexing to three additional units, at the cost of some challenging wiring and a ~40% hit in brightness.

    You are of course welcome to use the design of the Alpha Clock Five as a starting point (it's a fully open source project-- the schematics, circuit board designs, and part lists are all available for you to play with), and design a fully independent project. Another approach that you might consider would be to get two Alpha Clock Five (basic edition) kits, and connect them with a ribbon cable. The default firmware supports daisy chained display, and you could play with the firmware to make a stand-alone version that forms a single 8-digit clock. (The circuit boards can be tiled side to side seamlessly.)

    If you contact customer service, we can also pack a custom kit for you that includes just the number of displays that you want to purchase, and we do sell the individual components as well.

  • Thanks for the informative post. 

    So, just to check to see if I'm understanding this right: If it could be daisy chained like that, then I guess it would be possible to: get two clock kits, remove a display from each, and daisy chain the two now-four display clocks for a full functional 8 digit one? 

    As for what I'd need, does this look good?
    -2 Basic kits
    -FTDI Friend
    -6 Pin female to female header 

    A bit more advanced question(s). Say if I wanted to make this portable. With a battery, and a master switch to turn it on only when I need it (so the batt isn't constantly drained), but still have a power jack to plug in at home. Is this possible? 

  • Yes, that is all correct, with the note that the firmware does not have a mode that directly supports a clock spanning two units; you will need to play with the firmware to get it to do this function. We would recommend that you leave the Chronodot on one, and designate that as the controller, and have it send serial display commands to the second unit.

    Yes, you can potentially run from a power supply and switch. The red Alpha Clock runs at 5 V, and the blue/white version runs at 9 V.
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