It looks like the 5V voltage regulator may not like extremely cold temperatures. Here's a little background of my situation:
I am in Salt Lake City, UT. and we are looking at about 15F degrees or so at night. When turning everything on last night, all my LE's that were powered down would not power up when I turned them on. The 3.3v LED was lit, but everything else was dead. 3 out of 5 of my LE's were this way. The other two that were working, were powered on all day long.
So, I took one inside to troubleshoot, and within a minute or so, it powered on as normal and everything worked. I went out side and tried to warm up the 5V regulator on the other LE's with my hands, and what do you know, they started working. It seems that it doesn't take much heat to get them working again, but it does look like it doesn't like the cold all that much either. So here's my question:
What would you recommend to use to keep the inside of the box a little warmer, so I don't have this problem? I thought about using a little 20 watt bulb or something, but I wonder if theres something out there that is a little more effective and safe. I don't want to be heating it up all that much - just enough to keep it working.
Ideas?
-Brandon