TIME SWITCH WITH SOLAR FUNCTION

PURPOSE:To facilitate the solar setting by including a means of setting and inputting the latitude and longitude of the set position and an arithmetic memory section for calculating the sunrise and sunset time everyday based on the latitude and longitude to reduce errors due to difference in the latitude. CONSTITUTION:With the east longitude and the north latitude read out of a second memory 10 as parameter, an auxiliary number M is read out of a fourth memory 13 while an auxiliary number N out of a fifth memory, the current date done out of a calendar/timepiece section 8 and the sunrise and sunset time T0 of the former Tokyo Astronomical Observatory, out of a third memory 12 are searched. With time difference P=(sunrise time - sunset time)/2 as parameter, an auxiliary number (n) is read out of a sixth memory 15 and the time T0, and the numbers M, N and (n) are substituted into the formula to calculate the sunrise and sunset time T at the set position, which are memorized into a first memory 9 as solar control time.