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| Principle | The same as the clock at
Vitensenteret.
Electronic timebase. Time counted by number of balls in 4 trays. The ping pong balls are lifted by an air fan. |
| Building material | Mainly plywood. Balls are lifted in a plexiglass tube.
The complete clock is mounted on a wall. |
| Number of trays | 4 trays. A new ball arrives every 2 minutes.
Two trays count 2-minutes, 5 x 6 = 30. Two trays count hours, 6 x 4 = 24. |
| Fan arrangement | Low noise 12V fan with just enough power to lift a ball.
Electromagnet controlled entry mechanism for balls. |
| Electronics | Crystal oscillator timebase.
Microprocessor controlled functionality. Microchip PIC16F84 microcontroller. Everything, including fan powered through ordinary 12V AC/DC converter. |
| Project schedule | Start january 1998.
Finished may 1998. |
Last modified 5. nov 98