The noise is an output bit from a feedback shift register psuedo random number generator. A button press starts the timer which closes contacts of a reed relay for the duration set by the pot. Weather Station Measures temperature, wind speed and humidity. Temperature uses a National Semi. Humidity uses a Phillips humidity to capacitance transducer.
Wind speed is measured with a small thermister as a hot wire anemometer.
These are output by RS-232. Video Test Pattern Generator More or less standard bar, dot and crosshatch patterns as black and white interlaced composite video signals. A PIC running on a 14.31818MHz crystal oscillator does all the timing. Light Dimmer, serial contol Phase controlled triac lamp dimmer using the PIC for the timing. The lamps brightness can be made to slowly change up and down over time.