OT: Christmas light weirdness

[DP]

I have three identical strands of white pearl (little globes) lights for our tree. One strand isn't working and I can't find a burned out bulb because the globes are frosted. So I get my voltage detector figuring I can find where the current stops and that will be the burned out one. No such luck-it's reading current to the end.
I figure then to tediously pull each one out and put in a bulb that works until I find it. I get a bulb from the working strand (to use in the non-worker) which of course goes dark and I replace it with a bulb from the non-working strand. Surprise! The rest of the strand lights back up but the bulb I put in doesn't. OK, I grab another bulb from the non-working strand and it does the same thing. Try a third-yep! it also stays dark while the rest of the strand lights up.
I am no electrician but doesn't this seem weird? What's the explanation?
No, I haven't checked the fuses on the non-worker yet as they are ridiculously small and crammed in but if I have current to the end it wouldn't be the fuses, right?

[tenders]

Hey, I had the same problem!

I assumed that one bulb burned out, leaving a slightly too-high voltage across the rest of them. This voltage accelerated the burnout of another bulb, increasing the voltage across the rest, which led to the rest burning out faster and faster.

Perhaps if I'd replaced the original burnout soon enough, the other bulbs would've hung in there. But once the lights are mounted for the season I don't audit them.

I threw the non-working strand away. They're so cheap it wasn't worth troubleshooting with other bulbs.

[DP]

Very interesting! But if a bulb was burned out, tho', how would it allow current to flow in the working strand?
Another problem is that I bought these strings about five years ago and haven't seen any since.

[BigGuynRusty]

[quote DP]Very interesting! But if a bulb was burned out, tho', how would it allow current to flow in the working strand?
Another problem is that I bought these strings about five years ago and haven't seen any since. You have a bulb that is out of its socket, not burned out.
the reason a burnout doesn't cause darkness is the internal shunt.;
http://christmas.howstuffworks.com/chris...ights1.htm

BGnR

[DP]

Thanx all. Someone else old me about jumpers (shunts) too.
BGnR: What's "The EULA"?

[SteveO]

eula = end user license agreement

It's the agreement you stipulate to when you put new software in use. Also includes stuff like, you can only install this on x number of machines (usually one), do not eat the software, we are not responsible for misuse of the software, do not destroy the world with the software, etc.