On Thu, 11 Oct 2012 03:13:01 -0400, "Michael A. Terrell"
wrote:


Jeff Liebermann wrote:

On Mon, 8 Oct 2012 06:27:05 -0700 (PDT), George Herold
wrote:

Hi SEB. Well I sent an email to Don klipstein on this topic. And
have permission to copy his reply.
from Don K. below

2: In incandescent traffic signals, the bulbs for yellow last
longer than for red and green. So even after being switched on
and off about a million times, on-time is still a significant
factor in life expectancy.

That means for my proposed test comparing a 50% duty cycle flashing
light bulb, with one that is on continuously, the continuous light
bulb will burn out first. That's the opposite of what I saw with the
theater marquee bulbs. Now, I'm really tempted to run the experiment.


Was there any vibration in that theater marquee?

That's a good point. Were there any bulbs continuously lit on the marquee to
use as a reference?