A while back I noticed one thing that i see *everywhere* around construction equipment, but i don't see it anywhere in 1/14 stuff online...
I need an arrow board!
http://www.wanco.com/products/detail...148&type_id=10
Little math and caliper time later, i broke out the solder station.
http://www.555-timer-circuits.com/flashing-led.html
15 yellow 3mm LEDs, a 555 timer chip, 2 resistors, a capacitor, an on/off switch, and 3 position switch. I can turn my board on and off, or set it to point either direction, or as a center line for slow moving hazard.
I have it set as mono flash instead of sequential since that's all i ever see around here, and the circuit is much easier to build. Right now i'm sitting around 4 sec on 4 off, i need to play around with component values to get the flash rate up to 1/2 - 1 hz.
Then i'll need to get brass stock and build the trailer!
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Edit
Their site now shows the 15 light boards having 7 modes.
Mine has 2 modes. It can be 3 mode if you use a 3 position center off switch, but it's not the full line.