On 11/7/2011 7:59 AM, ---MIKE--- wrote:
I have an inexpensive bedroom clock. It is not an atomic clock and it
doesn't use WWV but somehow it always resets correctly at the time
change. I don't know how it does this.

---MIKE---

In the White Mountains of New Hampshire
(44� 15' N - Elevation 1580')

That one is programmed with the time change in the processor
inside the clock. I have one like that, only mine was built
before they changed the DST dates. So it is off by an hour
for a month in the Spring and an week in the Fall. The
thing that amazes me is how accurate it is. It hangs right
in there almost on time for months at a time. Of course
if the battery goes dead you lose it and have to reset it.

Bill