1986 年 32 巻 4 号 p. 236-247
A hand-held programable computer (SHARP PC 1501 with EC-150) has the function of both chronometer and chronograph as well as that of calculator. We construct a program for the computer, by which solar observation and its reduction can be performed for determining longitude and latitude of stations without the use of solar ephemeris. We also discuss the implication of the outputs. The dump-list of the program is shown in BASIC.