Disclaimer: This prop page is provided as-is, for informational purposes only, without warranty of any kind. You are solely responsible for any and all consequences of its use. Selecting this prop page and viewing the information constitutes acceptance of these terms.
Here's my version that looks really kewl and will be seen! My requirements: must run on battery power a long time---bonus, running on battery power will eliminate a long cord to run to the tree near the street where the TOTs can readily see them. Must be very visible, appear as random blinking, and be cheap!
To meet these requirements....it's time to use the most popular chip timer in the world....the 555. I actually used two 556 chips (which has two 555 timers in it) to drive 4 sets of LED pairs...at various SLOW blink cycles. All the electronics are driven with a single, safe 9 volt alkaline battery which lasts many many hours (days?) driving the eight LEDs through the 556 chips. I used a Radio Shack project box waterproofed around the edges with packaging tape...and with a small switch to turn it on and off.
Here's the schematic--click on it to get larger view.
I assembled the all the electronics on a perfboard shown here screwed into the project box. Here's a view of that. Note the LED eye wood blocks shown to the right.
I just connected the LED eyes via wire pairs to the project box. For the eyes to be seen at all, you must use bright LEDs and these really great "glass diamonds" at WalMart for $3 (pack of 20) in the Crafts department. I epoxied glass diamonds to the front of the LEDs to magnify the light.
Standard LEDs are about 10 mcds (millicandles) in brightness and are too dim. I found LEDs at Radio Shack that had greater than 700 mcd (millicandles) of light. Not cheap at Radio Shack, but a quick variety. I used a pair of 5 mm blue, yellow, and red LEDs...with a pair of 10 mm RED ones (with 5000 mcds each!). I didn't put the glass diamonds on the 10 mm ones--didn't need to--they are super bright already.
Then, I used speaker wire, whatever..any small gauge wire will do to connect up the LEDs. Then, just attached the LED eye wood blocks to various tree limbs that face the street.
Nothing special about assembling the wood blocks. They are basically just 7" x 1.5" scraps of cedar, spray painted black, with holes drilled in them...about 3" apart... to accept the LEDs (I used epoxy to hold the LEDs in the holes.) I put a screw on the back of the blocks to wrap the wires around to provide strain relief.