Actions
Forum Thread Details
  • Replies 20 replies
  • Subscribers 33 subscribers
  • Views 2263 views
  • Users 0 members are here
Related

Like-a-pro soccer display?

Former Member

Dear Ben,

I would love to make something special for the non professional soccer team my son plays for.

How difficult would it be to create a large (7-segment led ?) display the coach could use to call for players' substitutions during a match?


Design requirements:

-to have two pair of 2 digits separated by ":" (first pair red, second green)

-to be big/bright enough to be readable from 30 yards/meters in sun light

-to use self contained energy (a battery I suppose)

-to be portable, light and sturdy in the same time

-to be low cost

-to be easy to operate

 

Thank you in advance,

Carlo

Parents

  • Hi Carlo,

    If you use 3 LEDs per segment and 7 segment digits you need 42 red LEDs and 42 green LEDs.

    These cost about $15 - $20 / 100.

    You could use 4 BCD switches to control the digits at about $7 per switch.

    You could use 4 BDC to 7-segment decoder chips to drive each digit at about $1 each.

    You also need a resistor on each segment, a battery and a power switch.

    From there you need to decide how to connect everything (trade-off between labor and cost)

    Doug

  • in reply to dougw

    "You could use 4 BCD switches to control the digits at about $7 per switch."

     

    Yes, that would work.

     

    One rotary encoder switch would be cheaper. Push to select the digit, turn to change the digit. 4 inputs required. <$3.

    Left-right (select digit) and up-down (change value) is another option.

     

    A super-cheap bluetooth serial module (~$2) is an option. Serial into the Arduino and control it from your smartphone. No buttons, easy UI.

     

    For daylight visibility across a football field you probably do need high power LEDs @ >>50mA. Bright ones will be 350 - 700 mA.

    Not sure that you will get BCD-7 seg decoders that will drive that sort of current.

    4 x 7 matrix is fewer i/o lines (11) than 4 x 4 BCD (16).

     

    Arduino Nano should be enough. You can get those <$5.

  • in reply to Former Member

    The cheapest way to get a lot of bright LEDs connected up is to use some LED strip. Shop around and you can get some bargains. Cut the strip into lengths to form the segments. Stick them to a board and wire them up. They typically just need 12 on the end terminals. Series resistors are included.

    Get 60 LED/m. If you want denser spacing put two or more strips next to each other to form a segment.

Reply
  • in reply to Former Member

    The cheapest way to get a lot of bright LEDs connected up is to use some LED strip. Shop around and you can get some bargains. Cut the strip into lengths to form the segments. Stick them to a board and wire them up. They typically just need 12 on the end terminals. Series resistors are included.

    Get 60 LED/m. If you want denser spacing put two or more strips next to each other to form a segment.

Children
No Data