Junghans Watch Force Mega Solar 18/1401.00. Junghans is a pioneer in radio-controlled watch technology and is also at the forefront of solar energy for watches. These two technologies are combined in the Force Mega Solar model. The Connected radio-controlled solar movement calibre J615.84 draws its energy from a power reservoir that is continuously charged by solar cells in the dial. The entire device is housed in a ceramic case that is both lightweight and scratch-resistant. This watch combines high wearing comfort and coolness with enormous everyday usability.