More about light (490)

1-07-1984 | switches itself on (and off) This circuit forms a switch that can be triggered on (or off) at the onset of darkness and remain active for a...

1-07-1984 | july/august 1984 react at the speed of light The human eye has a certain "built- in" delay. This fact is used for films, TV sets, and fluore...

1-07-1984 | motion study by flash-light WARNING! The circuit of the stroboscope is connected directly to the mains and experiments on the opened unit ar...

1-07-1984 | protects your car battery Who has not at one time or another forgotten to switch off his car"s lights on a murky morning? That is not much o...

1-07-1984 | see the phone ringing In many instances it is not only the hard of hearing who are unable to hear the telephone ringing: even with normal he...

1-02-1984 | The essential ingredients for any self-respecting disco are well known, plenty of the right type of music, an abundance of coloured lights a...

1-12-1983 | The generator described in our November 1982 issue superimposes a high-frequency alternating voltage (uL) onto the direct- voltage output (U...

1-11-1983 | doorbell — or telephone - operated flash-light elektor november 1983 It was, of course, known before the outbreak of disco fever that flas...

1-10-1983 | solid-state dark room lighting elektor october 1983 LEDs are normally only used in those applications for which they were designed: as indic...

1-07-1983 | 2 constant light source In many occupations it is important that the light incidence at a certain location remains as nearly constant as pos...