An impressive and sophisticated mechanism as solution that (hardly)
nobody asks for a problem that (hardly) nobody has.
A sundial that indicates the civill time, gives you no more
information than you've already on your watch. A sundial that
indicates the real time, the solar time, is easy to read without
corrections and gives you information that you do'nt have.
Its challenge is that it incites to reflect about the difference
between civil time and reall time.
Willy LEENDERS
Hasselt in Flanders (Belgium)
www.wijzerweb.be
Op 27-sep-2009, om 6:48 heeft Robert Bargalló het volgende geschreven:
---------- Forwarded message ----------
From: Robert Bargalló <[email protected]>
Date: 2009/9/17
Subject: Direct reading time.
To: Robert Bargalló <[email protected]>
Hello All,
When an inexperienced person examine a well constructed Sundial,
often underestimate the instrument because it is not marking the
official time and having to make some “antipathetic” corrections of
the indicated time. That is the main reason we have built a sundial
that gives civil time accurately, enough to adjust the minute a non
solar clock that it has stopped. In a word, in our quadrant
needless resort to the equation of time or to the local position
versus the Meridian corresponding to the time zone. No arithmetic
corrections are needed.
Descriptively, the device is a horizontal sundial with a gnomon
consisting in thin thread nylon. The mechanism presents a 48 teeth
gear, powered by an endless screw, which allows the entire clock to
rotate some degrees around an axis parallel to the Earth rotation
axis (around the gnomon). In other words, the mobile set plays like
a hypothetical sundial indicating the exact civil time is
elsewhere, in another position but in the same geographic parallel.
As to the accuracy, the quadrant presents marks of all the minutes
from the 5 h 45 a.m. until the 8 h 15 p.m. The single need
featuring the device is that one or twice a week requires adjusts a
rotatable knob to indicate the current date. This disc, of course,
acts on the endless screw and, for that reason, on the rotation.
Really, the rotation movement compensates not only the equation of
the time, but also the error caused for the geographic longitude
position of the instrument.
For the same method we can use the sundial giving 3 types of time:
the local solar time, the standard time, or the daylight savings.
Since we installed it, from November 2006 to date, it has indicated
time with an error that in no case exceeded one minute.
Happy Dialling!
Robert Bargalló
More information at next blog
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