Building a Race Clock

Allow for TCP or UDP connection to the clock. Preferably UPD. I'm not personally a fan of wireless (802.11). I'd rather have a wired network.

Why not buy a used display that already works with Lynx if you are on a budget?

I'm not really on a budget, just thought it would be a fun project.

Who has used displays available? I don't see them all that often.

I've built two. They were a fun project. Cost was about $300 for each. One was a wired ethernet, the other used WiFi. We use the WiFi one on the 200m mark, and the wired one at the finish line. I'd say it took about 100 hours or so designing and building.

Basically I used a raspberry pi to perform the clock display logic and a virtual com port to send data from FinishLynx to the pi.

The clocks are made of 250 high intensity LEDs, organized as segmented strips in a ##:##.# fashion, and do a great job in bright sunlight.

I can post more info if anyone wants it.

I have built an ethernet clock using an arduino, worked great with lynx, only issue was that the LEDs weren't bright enough. Definitely a fun project

Love to see pictures! How bright are they?

The LEDs I used were rated at 20000mcd

http://www.amazon.com/Bluecell...light/dp/B006G6TKQW/

Each digit's segment is composed of 7 of these babies. They were so intense, that I actually had to diffuse them with two layers of fluorescent light diffusers.

Here's some pics:

At the track:
https://drive.google.com/file/...TZj/view?usp=sharing

Notice the battery. This 35ahr will run the clock for about 14 hours:
https://drive.google.com/file/...VEE/view?usp=sharing

Here's the clock at a distance
https://drive.google.com/file/...dnM/view?usp=sharing


And the electronic guts:
https://drive.google.com/file/...cDQ/view?usp=sharing

The Raspberry PI with WiFi:
https://drive.google.com/file/...QnM/view?usp=sharing

Wow... Cool stuff guys. Would love to see some of the Arduino clock pictures.
Thanks!

quote:

The clocks are made of 250 high intensity LEDs, organized as segmented strips in a ##:##.# fashion, and do a great job in bright sunlight.

Why only for displaying tenth?

Ciao

dirk

Well, When a race is happening, FinishLynx will only output a maximum resolution of a tenth of a second. For track we don't need any an hour digit, so for us, a clock that displays MM:SS.t is perfectly fine. This isn't a scoreboard - just a finish-line clock.

Ups - Our System will give us hundreth.
That's why I am wondering...

So do you start the clock manually? THEN we will have thenth only too...

Ciao

dirk

DudeMan this looks great. One question though: I can see you used wooden material for the housing. Are there any issues with water/humidity? Any side-effects of the black housing in terms of heat? Or are you using fans to blow out the heated air?
Cheers
ML

Yes, I used 1/8" wood for box since it is a material I can work with. As we are in SoCal, our youth track season (March-June) rarely gets wet, but that would be an area of improvement. Paint can only protect so much.

On the first clock I made, I used a PC power supply - which does generate enough to heat that I needed to vent, but a fan attached to the grill on side takes care of that. For the second clock that runs on battery, passive venting is all I needed.

Cheers!

Could you post a block schematic of the LYNX/RasPi arrangement and the logic which drives the LEDs? I can see you used discrete transistors (1 for each segment).
Thanks

Here's a sketch up of the LED array use for each segment on the clock, composed of 7 LED's and 7 100-ohm resistors going into a 2N2222a transistor that is driven by 74HC595 shift register.

https://drive.google.com/open?...x4MnFmZHM&authuser=0

And here is a sketch up of the PI to a BiDirectional Level Shifter to the 74HC595 shift register.

https://drive.google.com/open?...9zajZ0OW8&authuser=0

(Sorry for the rotated images).

I know this post is quite old but I've been thinking of a similar project
does your display need much code in order for it to interact with the FinishLynx system?

Hey,

Yes, the project does require quite a bit of programming and electrical engineering knowledge. I did complete the project, but it took a while. The design is not as robust as it could be but this is just my first version. Someday, I will make a better version.