- on Hobby & Modelling
- Published in issue 7/2010 on page 31
Cheap Bicycle Alarm
(Summer Circuits 2010 article)
The author wanted a very cheap and simple alarm for some of his possessions, such as his electrically assisted bicycle. This alarm is based on a cheap window alarm, which has a time-switch added to it with a 1-minute time-out. The output pulse of the 555 replaces the reed switch in the window alarm.