Wisconsin's variation of CDT

Larry Larry
Wed Jul 13 23:14:41 UTC 2011

Paul Eggert wrote:
> Robert Elz <kre at munnari.oz.au> writes:
>> Do you really believe that almost anyone (members of this list 
>> perhaps
>> excepted) actually changes their clock at the precise instant that 
>> DST (or summer time, or whatever it gets called in different areas) 
>> actually changes.
> Yes, I do.  Many people in this country no longer use watches; they 
> use cell phones to tell time.  And cell phones did change at 02:00 in 
> Wisconsin on April 2; see 
> <http://www.wisbusiness.com/index.iml?Article=58272>.

At 2 a.m. on April 2, most of the United States turns clocks ahead one hour as Daylight Saving Time begins. The clock function on wireless phones is controlled by information in the signal from the network on which the phone is located. U.S. Cellular uses Global Positioning Satellite (GPS) technology to set the time on its network, transferring that information to customer handsets. At 2 a.m., the network adjusts the wireless handsetÆs clock for Daylight Saving Time automatically, making each phone an accurate reflection of the current local time.

This argument is starting to recurse into itself;
1) If people in the state of Wisconsin tell time based on electronic equipment.
2) That equipment is keyed off of dataset that is incorrect for them.
3) That dataset should stay the way it is because this is how the people of Wisconsin tell time.

Isn't this a circular argument?

Please don't get me wrong...  I am just publishing my finding, and I expect that before March of 2007 this will all be a moot point.  When Wisconsin changes its law (as its dates will be wrong) I expect it will remove date and time and refer back to the U.S. law.  So I expect these finding to be of historical nature by the time anyone outside of this list sees them.

> I myself prefer an old-fashioned pocket watch, but I've observed that 
> my students, whose ages are typically around 20, use cell phones or 
> laptops to tell time just as often as they use watches -- perhaps even 
> more so.  Sales of cheap watches reportedly declined 10% last year in 
> the US, most likely due to the popularity of telling time by cell 
> phone; see 
> <http://www.news-journalonline.com/NewsJournalOnline/News/Headlines/frtHEAD03042406.htm>.

"Nowadays with all the electronic goods such as cell phones, iPods, the younger generation is more techno-savvy and they're relying upon electronics that they have and not wearing the watches."

Again, using data based on tzdata.

> I imagine that people who have to log times (nurses, doctors, police 
> officers, and fire departments, for example) make sure their clocks 
> are close to the consensus time.  These days no doubt a lot of this is 
> automated (mostly by our work, by Microsoft's, and by the cell phone
> companies') but that still counts.

Again, based on tzdata.

> I did consult some sources in Wisconsin for what people actually do, 
> and they agreed that 02:00 was the time people switched.  See, for 
> example,
> Bob Petrie, Locals prepare to lose sleep, gain daylight, Sheboygan 
> Press (2006-04-01) 
> <http://www.htrnews.com/apps/pbcs.dll/article?AID=/20060401/SHE0101/60
> 4010508/1062>

At 2 a.m. Sunday, Wisconsin makes the switch, which pushes sunset 60 minutes later into the evening. Sunday's sunset will be at 7:20 p.m.

It can be argued that this reporter hadn't checked his facts.

>> More likely to be relevant would be what time the radio stations 
>> announce during the "different" hour
> I'd be surprised if radio-station time announcements in Wisconsin 
> differed materially from the federal daylight-saving rules.

I have a number of phone calls out to different radio stations in regards to this, but it would not surprise me to find that they are using some device to track time and that it is linked back to using tzdata.

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