Also, in the meantime I have built quite an attractive solution using a small relay, that has been built into a Lego 'mailbox'. I will post a little tutorial on my site on building it, because I am rather charmed by the simplicity and robustness of (...) (22 years ago, 8-Sep-02, to lugnet.robotics)
(...) I hope this tutorial will give you some good ideas of your own too! It can be found here: (URL) please e-mail me with your comments or mistakes in the tutorial, or post it here. Have fun, Remko (22 years ago, 11-Sep-02, to lugnet.robotics)
