Press the red button (A2) to switch the instrument on. The instrument will power down 20 seconds after the last key has been pressed. All information stored, being retained.

按红色按钮(a2)将仪器启动，仪器将在20秒没有任何操作后关机。所有的信息将会被记录保留。

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The pen works as a transmitter: When you press down to write, a switch inside the pen turns it on.

WSJ: Pen and Paper Find a Place in the Digital World