For Guido Vollmar's complete instructions on how to build your automatic tea timer, click here. To view pictures and a schematic diagram of the tea timer, click here.
In search of the perfect cuppa, Guido engineered this simple, battery-operated tea timer with a built-in LED display. Just fix a tea-bag on the mechanism's extension arm, place a cup of hot water beneath it, and push a button according to the desired brew time. The microcontroller-operated, 5V circuit provides a servo motor with control pulses to lower and raise the extension arm. The brew process can be interrupted via a stop button, while the power supply is switched off automatically via FET.
Tea Timer Parts List
Allied Part #
100 nF Capacitor
330 pF Capacitor
10 µF Capacitor
470 µF Capacitor
BAV 100 Diode
400 mA Fuse
NO Push Button
Si 9430DY MOSFET
Additional parts required: IC1 PIC: 16C54; Servo motor like used in RC-toys; Old cookie box or similar package as housing; Short piece of wood for extension arm; Screws for mounting servo and protoboard; Assorted resistors (see detailed parts list online); Protoboard; Battery holder
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