This is a device that is designed to alert owls that it is nighttime. I made it for my little brother.
Step 1: Go and Get Stuff.
1 - Fake Stuffed Owl
1 - PC Board Grid-Style (Radioshack 276-150)
1 - PC Board IC-Style (Radioshack 276-159)
1 - 14 Pin Socket (Radioshack 276-1999)
1 - 9V Connector
1 - LM339 Chip (Radioshack 276-1712)
1 - SPST Rocker Switch (Radioshack 275-694)
2 - 2 digit 8 segment displays
1 - wire (black and red)
1 - 1K resistor
1 - photocell
1 - 9V battery
1 - 9V battery Holder (Radioshack 270-326B)
1 - tube of epoxy (not shown)
- soldering iron
- hot glue gun
- box cutter
Most everything can be purchased at Radioshack. I got the 8-segment displays at The Electronic Goldmine (goldmine-elec.com). Their part number was G4031. The owl should be purchased in San Francisco's Chinatown.