In order to see Luach displayed in Hebrew, you need Hebrew Support+ or Hebrew Lite enabled on your organizer. If you do not have Hebrew installed, the User Interface Language defaults to "English Only".

Luach can be used on all current models of the Palm Computing Platform running PalmOS 2.0 and higher.

Luach currently supports the years 1903 - 2072 (5663 - 5833).

The accuracy of the Zmanim calculations has not been completely validated. The current tests indicate an accuracy within plus/minus one minute when compared to other Jewish Calendar and Sunrise/Sunset programs. If there is ever a question as to the accuracy of Zmanim calculations, consult a halachic authority.

From Luach's main screen you can perform the following operations:

Set Luach Preferences (MENU icon)

Enable/Disable Luach Integration (Luach Integration checkbox)

View the Jewish Calendar (tap the Magen David button)

Set up the city definition for Zmanim calculations (Cities button)

Define User Events - yahrzeit, birthday, anniversary (User Events button)

Insert/Delete Luach Events into/from the Date Book (Events button)

Tap the Done button, or activate any other application to terminate the Luach application.

In order to access the Luach Preferences screen
tap the Menu silkscreen icon (bottom of the screen, to the left of the Graffiti area) OR touch the top left corner of the screen where you see "Luach Vx.x".
Now a drop down menu appears, select Preferences.

User Interface Language:

Checking English/Hebrew allows the display of dates, holiday names, "Parshat HaShavua" and "Sefirat HaOmer" to be displayed in Hebrew.

Checking English Only allows Luach to be operated without having "Hebrew Support" installed. All dates, holiday names, "Parshat HaShavua", and "Sefirat HaOmer" will be shown in English.

Holidays:

Checking Israel will cause the Holiday schedule that is observed in Israel to be used. The "Parshat HaShavua" will be determined based on the Israeli Holiday schedule.

Checking Diaspora will cause the Holiday schedule that is observed in the Diaspora to be used. The "Parshat HaShavua" will be determined based on the Diaspora Holiday schedule.

Tap the OK button, to return to the main screen of Luach.

For a list of Holidays, see the end of this manual.

The halacha involved in determining zmanim is quite complicated and there are many different opinions regarding these calculations. Luach is by no means a halachic authority on this subject, and if there is ever any doubt, you should consult a halachic authority.

Luach attempts to provide you with the most important Zmanim information. In addition, Luach allows you to configure zmanim to your own personal observance. Hopefully the flexibility provided in the Zmanim Preferences will cover most if not all different methods for zmanim calculations.

Many sources of information were consulted in developing this section of Luach. A partial list of sources are:

Books

Halachic Times by Rabbi Yehuda (Leo) Levi
Astronomical Algorithms by Jean Meeus
Zmanei HaHalacha L'Maaseh (Hebrew) by Yedidiyah Manat

Windows Software

HebCal by Joe Kohn, the Calendar Maven (http://www.calendar-maven.com)
Kaluach by Yisrael (Russ) Hersch (http://members.tripod.com/~kaluach)
Ephemeris Tool 2.2 by Manfred Dings (http://members.aol.com/DingsHMTSB/asappsen.htm)

Zmanim Preferences allow you to set certain settings related to the Zmanim and Shabbat calculations that are performed by Luach. Several of the settings can be specified as either Degrees or Minutes. Degrees refers to the number of degrees that the sun is below the horizon (before Sunrise or after Sunset). The number of degrees may correspond to a number of "equivalent minutes". According to Rabbi Levi's book, Halachic Times: "Equivalent Minutes is the number of actual minutes of the subject event in Jerusalem, at the equinox". When settings are specified in minutes, this refers to actual number of minutes before or after Sunrise or Sunset.

A detailed description of the parameters that can be set in the Zmanim Preferences screen is provided in the Displaying Zmanim section of this manual.

In order to access the Luach Preferences screen tap the Menu silkscreen icon (bottom of the screen, to the left of the Graffiti area) OR touch the top left corner of the screen where you see "Luach V1.20".
Now a drop down menu appears, select Zmanim Preferences.

Several of the Zmanim Preferences can be specified either as Degrees or Minutes. In order to change the settings between Minutes and Degrees, tap the appropriate Popup Trigger, and select the desired units. When specifying Degrees, the number of degrees should be entered as a decimal number. When specifying Minutes, the fractional part of the number should be set to 0. If it is set to anything other than 0, it will be ignored.

If you want to set your Zmanim according to the Magen Avraham, then use these settings:
Dawn (Alot): SR -20.0 Deg (Early Dawn)
Earliest Talit: SR - 50.0 Min (change if you need)
Latest Sh'ma: M"A (Magen Avraham method)
Dusk (Tzet): SS + 20.0 Deg (Rabeinu Tam)
Shabbat Ends: SS + 72.0 Min (late Shabbat)

Another common set up is to leave as is, but change:
Shabbat Ends: SS + 45 Min (45 minutes after sunset)

Tap the Save button so that the settings will be saved, and you will be returned to the Luach Main screen.

Tap the Cancel button in order to return to the Luach main screen without accepting any changes that were made

Tap the Set Defaults button in order to restore the Zmanim Preferences to their original default values. You still need to tap the Save button after restoring the default values in order to save these values.

From the main screen of Luach, tap the Cities button. The "Current City" is displayed at the top of the Cities screen. This is the city that will be used by Luach for Zmanim and Shabbat/Chag calculations.

Below the display of the current city is a Popup Trigger which will popup a list of all the cities that have been defined when it is tapped. A city can be selected from this list by tapping the name of the city. That will cause the list to close, and the city that was selected will be displayed in the Popup Trigger. That city can then be manipulated by tapping on any of the buttons at the bottom of the screen.

The city that is selected from the city list can be set as the current city by tapping the Set City as Current City button.

In order to take elevation into account for Jerusalem, see the FAQ.

In order to modify the definition of a city, select the city from the city list, and tap the Edit button.

To define a new city, tap the New button.

In order to delete a city definition, select the city to be deleted from the city list, and then tap the Delete button. You cannot delete the city that is set as the current city.

Tap the Done button to close this screen and return to the main Luach screen.

Luach allows a maximum of 50 cities to be defined. Once all 50 cities have been defined, no additional city definitions can be made. In order to define another city, first delete one of the existing city definitions.

The list of cities is not displayed in alphabetic order, but rather using a "Least Recently Used" algorithm. The "Current City" is always at the top of the list. Whenever the "Current City" is changed, the new "Current City" is moved to the top of the list, and all other cities are moved down in the list. Whenever a city definition is modified, or a new city is defined, that city will be moved to the second position in the list (after the "Current City"), and all other cities will be moved down. Using this algorithm, the cities that are most recently manipulated will stay near the top of the list, and cities that are not used too often will migrate towards the bottom of the list.

When tapping the Edit or New buttons on the "Cities" screen, the "City Definition" screen will be displayed. This allows you to define or edit the definitions of a city. On this screen there are fields for specifying:

City Name
Special Candle Lighting
Latitude
Longitude
Offset from GMT (Greenwich Mean Time)
The Daylight Savings Time (DST) characteristics of the city

Tapping the Save button will cause the data displayed on the form to be saved. If no city name has been defined, you won't be able to save the city definition. Tapping the Cancel button will cause any changes to be discarded. No warnings or confirmations are provided.

City
The City name can be up to 28 characters.

Special Candle Lighting
When this field is checked, any time set in the Zmanim Preferences for Candle Lighting will be over-ridden. Enter the number of minutes before sunset for candle lighting in this city. This is used for Jerusalem with a setting for -40 minutes.

Latitude
Latitude is specified in three parts; degrees, minutes and North/South. If the latitude of a city is specified as a negative number, then South should be selected to indicate a location that is south of the equator (for a positive number select North). There is currently no error checking being done on the Latitude fields. The degrees part should be between 0 and 90, and the minutes part should be between 0 and 59. Entering a number that is out of range may cause incorrect calculations. Calculations will not be accurate for locations which are too close to the North or South Poles.

Longitude
Longitude is entered in three parts; degrees, minutes and East/West. If the longitude of a city is specified as a negative number then East should be specified to indicate a location that is east of the Greenwich Meridian (for a positive number select West). There is currently no error checking being done on the Longitude fields. The degrees part should be between 0 and 180, and the minutes part should be between 0 and 59. Entering a number which is out of range may cause incorrect calculations.

Offset from GMT
The Time Offset is the time zone with respect to Universal Time (UTC) or Greenwich Mean Time (GMT). You should select "-" for cities which are West of Greenwich, England and "+" for cities which are East of Greenwich, England (e.g., New York is "-5", while Israel is "+2"). There is currently no error checking being done on this field. The numbers in this field should be between 0 and 12. Entering a number which is out of range may cause incorrect calculations.

Daylight Savings Time
Daylight Savings Time (DST) can be specified as Off, On or Auto.

Setting Daylight Savings Time to Off will cause the program to assume that Daylight Savings Time is never in effect for the specified city when calculating Sunrise, Sunset and other time based calculations.

Setting Daylight Savings Time to On will cause the program to assume that Daylight Savings Time is always in effect for the specified city when calculating Sunrise, Sunset and other time based calculations.

Setting Daylight Savings Time to Auto will allow Luach to use the Start and End dates to determine when Daylight Savings Time is observed in a particular city. The Start and End dates are determined by specifying the occurrence of the day-of-the-week and month (e.g. First Sunday in April). Any Zmanim calculations will be made based on whether the date that the calculation is made for is in the Daylight Savings Time range or not.

When a new city is defined, Daylight Savings Time will be set to Auto by default, and the Start and End dates will be set to First Sunday in April and Last Sunday in October. This is the setting for most cities in the USA. In most European cites DST starts on the "Last Sunday in March" and ends on the "Last Sunday in October". In Israel the starting and ending dates of DST change every year. For Israeli cities, make sure to update the "Start" and "End" dates based on the dates that will be used in the current year. For other cities that have a fixed schedule for DST, make sure to set the Start and End dates appropriately. For cities that never observe DST, select the Off setting.

In order to make it easy to add additional city definitions, Luach includes the "cities.txt" and "cities.prc" files. These files contain city definitions for about 200 cities throughout the world. The "cities.txt" file is a standard text file and may be viewed with any text editor or word processor. The "cities.prc" file is in the Palm's standard Doc format, and can be loaded onto the Palm, and viewed with any compatible Doc reader (e.g., TealDoc, AportisDoc). For additional city definitions see the AstroDienst web site.

The User Events function allows the definition of events that occur based on the Jewish Calendar. The events that can be defined are Yahrzeits (the anniversary of a death), Birthdays, and Anniversaries. Defining a User Event allows you to keep track of the secular date on which these events occur on each year. User Events can be inserted into the Datebook using the Event Management function (see Event Management). User events are graphically displayed in the Integrated Jewish Calendar by a small rectangle next to the day of the month. (see The Jewish Calendar Dialog).

From the main screen of Luach, tap the User Events button.

View the selected User Event and see when these events occur in different years
Edit User Events
Define New User Events
Delete User Events

At the top of the User Events screen is a Popup Trigger which displays the description of the currently selected User Event (if no events have been defined this will be indicated on the screen). When the User Events screen is activated from the main screen, the "User Event" that will occur next in the calendar, is selected automatically. Tapping on the description will open a list of all of the User Events that have been defined. The list is sorted chronologically in the order of the next occurrence of each event from the current system date. Tapping on another event in the list will cause that event to be selected, and its details will be displayed.

In addition to the description of the selected event, the event's type (Yahrzeit, Birthday, Anniversary) is displayed, and the Defined Date (the secular and Hebrew dates on which the event originally occurred) is displayed. Below this, the Occurs On field shows the secular and Hebrew dates of the next occurrence of this event. Tapping on either of these dates will cause the Jewish Calendar dialog to be displayed. Selecting a date will not cause either of these dates to be changed, but will just return to the "User Events" screen.

Below the Occurs On dates are three buttons - a left arrow, a button containing a number, and a right arrow. The left and right arrow buttons are repeating buttons that will change the Occurs On date to the previous or next year respectively. Holding the stylus down on either of these buttons will cause the year to increment or decrement rapidly. The button between the two arrow keys, displays a number which is the number of years that have passed from the Defined Date until the currently displayed Occurs On date. Tapping on this button will set the Occurs On date to the "next occurrence" of this event (i.e., it will reset the date to the date that was displayed upon entering this screen). If the event is defined as a Birthday, and the year is already on the "next occurrence", then tapping this button will change the date to display the 13th birthday. This can be useful in calculating Bar Mitzvahs. When the 13th birthday is shown, just tap on the Occurs On date in order to view the Jewish Calendar dialog.

Select the next Shabbat, and tap the  button in order to see the "Parshat HaShavua" for the Bar Mitzvah.

Tapping the Edit button will cause the "User Event Definition" form to be displayed with the data of the currently selected event. Tapping the New button will cause an empty "User Event Definition" form to be displayed. In order to delete the selected event, tap on the Delete button. An alert box asking for confirmation will be displayed before the event is deleted.

The "User Event Definition" form is used to define new User Events and to edit existing User Events. The operation is the same for both of these actions, except for the initial data that is shown on the form. When editing an existing User Event the data that was defined for that event, will be displayed. When editing a new User Event, an empty form will be displayed. The appropriate fields must be filled in before the form can be saved. The "User Event" form contains the following fields:

Description - a description of the event
Type - allows you to specify the event as a Yahrzeit, Birthday, or Anniversary
Date - the secular date of the event
Jewish Date - the Jewish date of the event
After Sunset - a checkbox which allows you to specify if the event occurred after sunset on the secular date

Enter a description (maximum 28 characters). If you have Hebrew installed, you can enter the description in Hebrew.

Select the event's type by tapping on Yahrzeit, Birthday, or Anniversary.
NOTE: If a Yahrzeit is defined in Adar, then in a leap year, it will fall out on Adar Aleph. If this is not your minhag, then in the description of the event, tap the "Birthday" button and not "Yahrzeit". Then the event will fall out on Adar Bet.

Tap on either the Date or Jewish Date selector fields. This will allow you to select the date that the event occurred on. Tapping on the Date field will bring you to the Jewish Calendar screen using secular dates, and tapping on the Jewish Date field will bring you to the Jewish Calendar screen using Jewish dates. (see Selecting a Date).

If the event occurred after sunset (but before midnight) on the specified date, check the After Sunset checkbox. If you selected the date using the Jewish Date, the secular date will be shifted to the previous day, and if you selected the date using the secular date, the Jewish Date will be shifted to the next day.

Tapping the Cancel button causes any changes that have been made to be lost. The form will be closed, and you will be returned to the "User Event" form. Tapping the Save button causes any changes to be saved. The form will be closed, and you will be returned to the "User Event" form.

The "Event Management" screen lets you insert certain events into the Palm's Datebook, or delete them from the Datebook.

The events that can be inserted are:
- Jewish Dates
- Jewish Holidays (see list at end of this manual)
- Rosh Hodesh
- User Events.

Each event that is inserted into the Datebook, is inserted as an "Untimed Event" for the day that it occurs. "Untimed Events" are displayed at the beginning of each day in the day view of the Datebook application.

Note: In order to see "Untimed Events" in the month view, make sure that "Show Untimed Events" is checked in Menu/ Options/ Display Options of the Date Book.

There is no alarm set for these events.

From the main screen of Luach, tap the Events button, to display the Event Management screen.

The Start Date and End Date specify the range of dates for which events will be inserted or deleted. Tapping either of these dates will activate the Jewish Calendar dialog, so that you can select the desired date.

The Action is selected by tapping on Insert or Delete. Selecting either one of these will automatically deselect the other one.

Selecting an Event Type determines which type will be inserted (or deleted) into the Datebook. Selecting one of these will automatically deselect the other one.

If Dates is selected, the Jewish Date for each day in the specified range of dates will be inserted into (or deleted from) the Datebook.

If Holidays is selected, any Jewish Holiday that occurs in the specified range of dates will be inserted into (or deleted from) the Datebook on the appropriate date. See Table of Luach Holidays.
If a holiday has been moved from its normal date to a different date, the holiday name now has an asterisk (*) at the end of the name, in order to indicate that it has been moved from its original date.
For Details.

If Rosh Hodesh is selected, any Rosh Hodesh that occurs in the specified range of dates will be inserted into (or deleted from) the Datebook on the appropriate date.

If User Events is selected, any User Event that occurs in the specified range of dates will be inserted into (or deleted from) the Datebook on the appropriate date.

Once you have selected the Start Date and End Date, and specified the Action and Event Type, tap the "Process...." button, to insert/delete the events. A screen displaying the message "Processing.... 50%" will be shown. This message will remain on the screen while the dates are being inserted (or deleted), and the percent counter will change to indicate the percentage of completion. This could take several minutes depending on the date range that was selected. Once the operation has been completed, there will be a short beep, and the "Processing..." message will disappear. You can now view the Datebook, to see the entries inserted (or deleted) as untimed events within the date range selected.

Tap the Done button to close this screen and return to the main Luach screen.

The language (English or Hebrew) for the text for Dates, Holidays or Rosh Hodesh is determined by the User Interface Language setting. Luach provides support for an "English Only" mode. If your Desktop Computer doesn't support Hebrew, you may want to set Luach preferences to "English Only" when inserting Dates/Holidays/Rosh Hodesh into the Datebook. By doing this, you can insert these events into the Datebook in English. When deleting events from the Datebook, you must make sure that the language that was used for inserting is the same one that will be used to delete them.

If an event that is to be inserted already exists in the Datebook, it will not be duplicated. If the text of any event that has been inserted into the Datebook by Luach is modified, the event will not be deleted by Luach.

Since the Jewish Calendar can be made available from within the Palm's Datebook application, it is not necessary to have all of the Jewish Holidays and Jewish Dates inserted into the Datebook. Particularly, it may not be necessary to keep events that have already passed in the Datebook.

There are 54 Jewish Holidays which are supported by Luach. Therefore, inserting Jewish Holidays for one "Jewish" year will cause 54 events to be entered into the Datebook (this may vary slightly for a secular year), and will use approximately 2 Kbytes of memory.

When inserting Jewish Dates, there will be an event for each day in the range specified. A month of Jewish Dates will cause about 30 events to be inserted, and will use approximately 1.3 Kbytes of memory.

The suggested strategy (feel free to change this based on your personal needs) for managing Jewish Calendar events would be to decide how many years of Holidays you'd like in the Datebook (e.g., the current year, and the next 3 years), and insert these Holidays into the Datebook. After that, once a year, you can delete the old year's holidays, and insert another year of holidays. Similarly, decide how many months of Jewish Dates you'd like to have in your calendar, and insert these dates. At the beginning of each month, delete the oldest month's dates, and insert another month of dates. This strategy will keep the number of Jewish Calendar events in your Datebook fairly constant. By deleting old events, you will not fill up the memory with events that are no longer needed.

As an example, if you always have 10 years of Jewish Holidays in your Datebook, this will be 540 events, and use about 120 Kbytes of memory. If you always have 4 months of Jewish Dates in your Datebook, this will be about 120 events, and use about 5 Kbytes of memory.

If you regularly "Purge" events via the Datebook's purge function, it will not be necessary to delete events using the Jewish Calendar.

The User Events function allows the definition of events that occur based on the Jewish Calendar. The events that can be defined are Yahrzeits (the anniversary of a death), Birthdays, and Anniversaries. Defining a User Event allows you to keep track of the secular date on which these events occur on each year. User Events can be inserted into the Datebook using the Event Management function (see Event Management). User events are graphically displayed in the Integrated Jewish Calendar by a small rectangle next to the day of the month. (see The Jewish Calendar Dialog).

The User Events function allows the definition of events that occur based on the Jewish Calendar. The events that can be defined are Yahrzeits (the anniversary of a death), Birthdays, and Anniversaries. Defining a User Event allows you to keep track of the secular date on which these events occur on each year. User Events can be inserted into the Datebook using the Event Management function (see Event Management). User events are graphically displayed in the Integrated Jewish Calendar by a small rectangle next to the day of the month. (see The Jewish Calendar Dialog).

Whenever the Jewish Calendar dialog is displayed, a regular (Gregorian) calendar will be shown. This calendar looks different than the Palm's standard calendar that is normally shown. The month is displayed at the top of the screen on the left side, and the year is displayed on the right side. There is a grid which shows the days of the month, with the selected day highlighted.

There are graphical indicators within the grid that indicate special days on the Jewish Calendar:

- A Jewish Holiday which is a "Yom Tov", will have either a solid black line on the bottom of any day on monochrome devices, or red on color devices.
- A Jewish Holiday or other special day on the Jewish Calendar that is not a "Yom Tov" (e.g., Chol Hamoed, Chanukah, minor fast days, etc.), will have either a dotted line on the bottom of any day on monochrome devices, or orange on color devices.
- Most Jewish Holidays begin in the evening, this is indicated on the calendar grid with the line starting on the previous day.
- There are certain fast days which do not begin in the evening, this is indicated by a dotted line which does not completely fill the grid for that day.
- Rosh Hodesh is indicated by a small black circle on monochrome devices, or a yellow circle on color devices. This circle appears next to the day of the month. Rosh Hodesh is on the first of every Jewish month (except Tishrei), and also on the 30th of any month that has 30 days.
- User Events are indicated by a black rectangle on monochrome devices, or a blue rectangle on color devices. This rectangle appears next to the day of the month.

If the "User Interface" in the Luach Preferences is set for "English/Hebrew", the days of the week are shown above the grid using Hebrew letters ("aleph" for Sunday, "bet" for Monday, ..., "shin" for Shabbat").

Below the grid on the right side, are three fields (of which 2 are buttons).

The top field will show the name of the holiday, if there is a holiday on the selected date. If the selected date is Rosh Hodesh this will be displayed in the top field as well (except on Chanukah, when Rosh Hodesh and a holiday coincide - in that case, Rosh Hodesh is displayed in the middle field.)

The middle button is used to show the counting of the Omer. Tap this button to display the complete Omer text.

The bottom button shows the Jewish date corresponding to the selected date on the calendar. Tap this button to swap the calendar mode (Jewish/Gregorian).

Below the grid on the left side, are 2 buttons: and

Tap the button when the selected day is Friday, Saturday, Erev-Chag or Chag to display Shabbat/Chag Info. For additional details see Displaying Shabbat/Chag.

Tap the button to display all of the user events occurring on the selected date. For additional details see Displaying User Events.

There are four buttons along the bottom of the screen.

Tap Cancel to close the Jewish Calendar. The Palm will return to the application from which the Calendar was activated, however the application will return to the date that was selected prior to activating the Jewish Calendar, even if a different date was selected in the Jewish Calendar.

Tap Today to cause today's date to be selected. The Gregorian date and the Jewish date will both be updated.

Tap OK to close the Jewish Calendar. The Palm will return to the application from which the calendar was activated, and the application will be updated with the last date that was selected in the Jewish Calendar dialog.

Tap the Zmanim button to display Sunrise, Sunset and other "Zmanim" for the selected date. For additional details see Displaying the Zmanim

In order to display details of User Events occurring on the selected day, tap the button. Any User Event occurring on the selected day will be displayed.

The Shabbat/Chag information is initially based on the Current City that is specified in the Luach application (see Cities/City Management), however a different city can be selected by tapping on the city name. The Israel/Diaspora setting is set in Luach Preferences.

At the top of the Shabbat/Chag Info screen the city name is displayed along with an indication of whether daylight savings time is active (DST) or not (ST). Below the city name is an indication of whether Luach is set for Israel or Diaspora Observance. Below this indication the date of the selected day is displayed.

The Shabbat or Chag candle lighting time and the time for the End of Shabbat/Chag will be displayed. In certain cases, two candle lighting times will be displayed.

In addition, the "Parsha" will be displayed. If it is a special Shabbat, this will be displayed as well. Special Shabbatot that are shown are: Shabbat Shuva, Parshat Shekalim, Parshat Zachor, Parshat Parah, Parshat HaHodesh, Shabbat HaGadol, Shabbat Hazon, Shabbat Nachamu, Shabbat Mevarchim, Machar Hodesh, Rosh Hodesh, Chol Hamoed Pesach and Sukkot, and Chanukah.

The language of the "Parshat HaShavua" and special Shabbat text is determined by the User Interface Language setting.

If you want to see Shabbat/Chag info for a different city, tap on the city name and a list of available cities will appear. Choose a city from the list. Tap on the Select button to select the new city temporarily. The Shabbat/Chag info will be updated for the new city. This temporary city selection will remain in effect until you exit the Jewish Calendar Dialog. Tap on the Set City as Current City button to set the selected city as the new current city. The Shabbat/Chag info will be updated for the new city. Tap on the Cancel button to return to the Shabbat/Chag info screen without changing the city setting.

In order to display Zmanim for the selected date, tap on the Zmanim button. The Zmanim information is initially based on the Current City that is specified in the Luach application (see Cities/City Management), however a different city can be selected by tapping on the city name. The Israel/Diaspora setting is set in Luach Preferences. For information on how to change the Zmanim settings, see Zmanim Preferences. Some Zmanim calculations are based on the Sunrise and Sunset which are determined by the Latitude and Longitude specified for the selected city.

The accuracy of the Zmanim calculations cannot be completely validated. The current tests indicate an accuracy within plus/minus one minute when comparing to other Jewish Calendar and Sunrise/Sunset programs. If there is ever a question as to the accuracy of Zmanim calculations, consult a halachic authority.

At the top of the Zmanim screen, the selected city and selected date are displayed along with an indication of whether daylight savings time is active (DST) or not (ST). You can tap the city name in order to select a different city.

Tap the OK button, to return to the calendar.

According to the "Default Zmanim Preference screen", you would see these Zmanim times:

According to the "Magen Avraham Zmanim Preference screen", you would see these Zmanim times:

The following is a description of the fields displayed on the Zmanim screen, and how they can be configured in the Zmanim Preferences screen.

Sha'a Zmanit: 1/12 of the time between Sunrise and Sunset (h:mm:ss).

Dawn (Alot): Alot HaShachar. One of the most widely used definitions is 72 equivalent minutes before sunrise (SR - 16.10 Deg.), as specified by Rambam (this is the default). Another option is "Early Dawn" which is 90 equivalent minutes before sunrise (SR - 20.00 Deg.). Other values in degrees or minutes may be used.

Earliest Talit: The earliest time for putting on Talit and Tefillen. One common value used is when the sun is 11 degrees below the horizon (this is the default SR - 11.0 Deg.). Other values that are used include 10.20 degrees below the horizon (SR - 10.20 Deg.), as well as 50 or 60 regular minutes before sunrise (SR - 50 Min. or SR - 60 Min.). Any of these values can be specified in Luach.

Sunrise (Netz): Calculated based on Latitude and Longitude of the selected city. Sunrise is when the sun is 0.8333 degrees below the horizon.

Latest Sh'ma: The latest time that Sh'ma may be recited. This can be specified using one of two methods - the Magen Avraham (M"A) or the Vilna Gaon (GR"O). The day as specified by the M"A begins at Dawn (Alot HaShachar) and ends at Dusk (Tzet HaKochavim). Latest Sh'ma based on the M"A is 1/4 of an M"A day, which is determined by calculating 1/4 of the number of minutes between Dawn and Dusk, and adding that number of minutes to the time of Dawn. The day as specified by the GR"O starts at Sunrise and ends at Sunset. Latest Sh'ma based on the GR"O is 1/4 of a GR"O day, which is determined by calculating 1/4 of the number of minutes between Sunrise and Sunset, and adding that number of minutes to the time of Sunrise. The default setting for calculating Latest Sh'ma is to use the GR"O method.

Hatzot Hayom: Midday. Halfway between Sunrise and Sunset.

Mincha Gedola: This is the earliest that Mincha may be recited. This is 30 minutes after Hatzot Hayom. The 30 minutes can be specified in one of three ways. "30 Regular Minutes" is exactly 30 minutes. "30 Proportional Minutes" is half of a "Sha'a Zmanit". "30 Strict Minutes" is the same as "30 Proportional Minutes" unless this value is less than 30 minutes. If it is less than 30 minutes, then 30 minutes is used as the value. The default setting for Luach is "30 Strict Minutes".

Plag Hamincha: 1.25 Sha'ot Zmaniot before Sunset.

Sunset (Shkia): Calculated based on Latitude and Longitude of the selected city. Sunset is when the sun is 0.8333 degrees below the horizon.

Dusk (Tzet): Tzet HaKochavim. Two of the widely accepted values for specifying Dusk are: 24 equivalent minutes after Sunset (SS + 6 Deg) as specified by Rav (this is the default), or 90 equivalent minutes after Sunset as specified by Rabeinu Tam (SS + 20 Deg.). Others values that are used sometimes, include 72 minutes after sunset (SS + 72 Min.).

Light Candles: Candle lighting is usually 18 minutes before sunset (SS - 18 Min.). This is the default setting. There are certain cities which use different values for candle lighting time (e.g. in Jerusalem the custom is to light candles 40 minutes before sunset). Rather than needing to change the Zmanim preferences whenever switching to a city with a different candle lighting time, Luach allows you to override the candle lighting time for any defined city. This is done in by checking the "Special Candle Lighting" checkbox in the City Definition screen, and specifying the number of minutes before Sunset. Any city for which this checkbox is not checked will use the Candle Lighting specified in the Zmanim Preferences screen. When candle lighting time is displayed, if the selected city uses Special Candle Lighting, this value will be used in place of the Zmanim Preference value.

Shabbat Ends: According to R.Y.M. Tukaczinsky, shabbat ends when the sun is 8.5 degrees below the horizon (SS + 8.5 Deg.). This corresponds to "3 small stars visible" and is the default value used by Luach. Other values that are commonly used include 42, 45, or 72 minutes after sunset (SS + 42 Min., SS + 45 Min., or SS + 72 Min.).

If you want to see Zmanim for a different city, tap on the city name and a list of available cities will appear. Choose a city from the list. Tap on the Select button to select the new city temporarily. The Zmanim will be updated for the new city. This temporary city selection will remain in effect until you exit the Jewish Calendar Dialog. Tap on the Set City as Current City button to set the selected city as the new current city. The Zmanim will be updated for the new city. Tap on the Cancel button to return to the Zmanim screen without changing the city setting.

In order to delete Luach, tap the Luach icon, and make sure that the Luach Integration checkbox is NOT checked. Now you can delete Luach by selecting "Menu/Delete" from the Application Launcher. If you have inserted any dates or holidays into the Palm's Datebook, you may want to delete them before deleting Luach. Leaving these items won't cause any problems, but if you want to delete them after Luach has been deleted, you'll need to do that from the Datebook application.

Erev Rosh HaShana

Erev Rosh HaShana

Rosh HaShana (1)

Rosh HaShana (1)

Rosh HaShana (2)

Rosh HaShana (2)

Tzom Gedaliah

Tzom Gedaliah

Erev Yom Kippur

Erev Yom Kippur

Yom Kippur

Yom Kippur

Erev Sukkot

Erev Sukkot

Sukkot 

Sukkot (1)

Chol Hamoed Sukkot (1) 

Sukkot (2)

Chol Hamoed Sukkot (2) 

Chol Hamoed Sukkot (1) 

Chol Hamoed Sukkot (3)

Chol Hamoed Sukkot (2) 

Chol Hamoed Sukkot (4)

Chol Hamoed Sukkot (3) 

Chol Hamoed Sukkot (5)

Chol Hamoed Sukkot (4)

Hoshana Raba

Hoshana Raba

Simchat Torah

Shmini Atzeret 

Erev Chanukah

Simchat Torah

Chanukah (1)

Erev Chanukah

Chanukah (2)

Chanukah (1)

Chanukah (3)

Chanukah (2)

Chanukah (4)

Chanukah (3)

Chanukah (5)

Chanukah (4)

Chanukah (6)

Chanukah (5)

Chanukah (7)

Chanukah (6)

Chanukah (8)

Chanukah (7)

Asara B'Tevet

Chanukah (8)

Erev Tu B'Shevat

Asara B'Tevet

Tu B'Shevat

Erev Tu B'Shevat

Ta'anit Esther

Tu B'Shevat

Purim

Ta'anit Esther

Shushan Purim

Purim

Erev Pesach

Erev Pesach

Pesach

Pesach (1)

Chol HaMoed Pesach (1)

Pesach (2)

Chol HaMoed Pesach (2)

Chol HaMoed Pesach (1)

Chol HaMoed Pesach (3)

Chol HaMoed Pesach (2)

Chol HaMoed Pesach (4)

Chol HaMoed Pesach (3)

Chol HaMoed Pesach (5)

Chol HaMoed Pesach (4)

7th Day of Pesach 

Pesach (7)

Erev Yom Ha'Shoah

Pesach (8)

Yom Ha'Shoah

Erev Yom Ha'Shoah

Erev Yom Ha'Zikaron

Yom Ha'Shoah

Yom Ha'Zikaron

Erev Yom Ha'Zikaron

Yom Ha'Atzmaut

Yom Ha'Zikaron

Erev Lag B'Omer

Yom Ha'Atzmaut

Lag B'Omer

Erev Lag B'Omer

Erev Yom Yerushalayim

Lag B'Omer

Yom Yerushalayim

Erev Yom Yerushalayim

Erev Shavuot

Yom Yerushalayim

Shavuot

Erev Shavuot

17th of Tammuz

Shavuot (1)

Erev Tisha B'Av

Shavuot (2)

Tisha B'Av

17th of Tammuz

Erev Tu B'Av

Erev Tisha B'Av

Tu B'Av

Tisha B'Av