There is a prohibition against turning on or off circuits or switches on the Sabbath. Because of this, normal alarm clocks cannot be used on the Sabbath, because the user would not be able to turn off the alarm and it would go of for the rest of the day. There do exist Sabbath alarms which go off for 30 seconds and then shut off automatically, but they still annoy anyone in the room while they’re going off and if the user is sleeping very deeply, won’t work. These reasons, combined with my own personal preference to make my own things, led me to design a Sabbath alarm that I could use. The original design came from my Roommate Alarm Clock. When I scrapped that idea, I was left with a virtually soundproof container. Using my iPod as an alarm, I had an alarm that would wake me up just as it would during the week but that I could still silence immediately upon waking without violating any prohibitions.
Moving from the inside to the outside, the first layer is foam from an old yoga mat. Around that is a very dense cardboard cylinder, followed by more foam, followed by a layer of cloth, in this case socks. All this is put into another, thinner container, to hold it together.
The lid is made of layers of foam and wood and held on with cords to seal the container tightly, although this is not usually necessary.
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