YES Watch Frequently Asked Questions

How does the time zone map work?
The world is divided into 24 time zones starting with Greenwich, UK at the 00 time zone. The +1 through +12 is counted eastwards, and -1 through- 12 is counted westwards until they meet at the date line cutting through the Pacific. Each time zone corresponds to 15 degrees but, over land, time zones are determined by geographical and national lines. Some countries have 30 minute time zones.

For a complete listing of the time zone data in the YES watch please see
City Listing

The YES watch can be set by latitude and longitude.

See your YES watch instruction manual for further DST info.

How does military time work?
Military time counts time from 0000, starting at midnight up to 2359 next midnight GMT. Military time is sometimes called ZULU or 24 hour time and does not consider DST.

What is GMT?
GMT stands for Greenwich Mean Time. For more information about Greenwich Mean Time, its history and relation to other time standards, click this link to the Wikipedia article on Greenwich Mean Time.

How does latitude and longitude affect time?
Times for sunrise and sunset, moonrise and moonset change depending on where you are on the planet, or, what your latitude and longitude is. The equator is latitude 00 while GMT sits on longitude 00.

What is the story behind Daylight Saving Time?
A long time ago, before electricity made its inroads, society implemented Daylight Saving Time, DST, to accommodate the working man and woman. Basically, during summer time, they moved the hours one hour up to get more social time in the evenings. There are more than a dozen different Daylight Saving Time systems across the world, some of which are decided annually by local governments.

What are equinox and solstice?
The sun turns 4 days out of the solar year of 365.4 days. Equinox, the only two days of the year when the days and the nights are each 12 hours long, is the day when the sun passes the equator. The equinox day/night is the template for all traditional watches and clocks. Fall Equinox falls around September 21st, and Spring Equinox around March 21st. Then we have the two solstices which is when the days are long and the nights are short, or vice versa if you are "down under". Summer Solstice falls around June 21st and Winter Solstice falls around December 21st. These 4 points of solar time, along with the moon, have been the foundation of time keeping across cultures since the dawn of time.

What does a full moon signify?
The full moon is the highlight of the lunar cycle. From full moon to new moon it takes about two weeks, and who among us has not felt the power of a full moon? It takes four weeks (28.4 days) for a lunar cycle to complete. The moon causes the tide and influences many life giving cycles.

Battery Replacement
Here's a useful visual Yes Watch Battery Replacement How-To from Rainy Day Magazine, for independent spirits would like to do it themselves. The illustration is with a Yes Cosmo, but the principles and tools used apply to all YES watches.