All posts in the 'Alarm Projects' Category
Posted on 03 Jul 2008
The projet built using the OOPIC microcontroller.Features:
- Each day of the week can be set independently to any of 4 times or disabled
- Crescendo alarm (starts soft and gets louder until you wake-up).
- Each day’s alarm can be set to skip one week, alarm resumes the next week.
- Each day’s alarm can be set to a different time for one week, alarm resumes normal time the next week.
[more]
Posted on 11 May 2008
This circuit features automatic Exit and Entry delays - timed Bell/Siren cut-off - and system reset. It has provision for normally-open and normally-closed switches - and will suit all of the usual input devices (Pressure Mats, Magnetic Reed Contacts, Foil Tape, PIRs and Inertia Sensors). [more]
Posted on 11 May 2008
Joel Avrunin writes:The high-tech student of today has many tools at his disposal for keeping track of his hectic schedule. From computer date books to Palm Pilots, every event can be tracked. But however well organized he is, nothing will help him if he is oversleeps. The alarm on a personal organizer is too quiet, and most alarm clocks offer limited functionality. To solve both problems, we developed an alarm clock for today’s world.Our alarm clock features a large, bright time display, easily visible in the bedroom. It also features a loud, irritating alarm, sure to wake even the soundest of sleepers. By far the most innovative part of the alarm is the LCD display, which gives the date, alarm status, and status for setting the clock.[more]
Posted on 11 May 2008
The project uses a PIC16C84 to monitor 4 NC alarm inputs that when triggered, activates an output relay. The first zone triggered is illuminated with a solid lit LED, while the second and subsequent zones are indicated with a flashing LED.This project serves as a complete, although relatively basic introduction to digital electronics, PIC microprocessor programming and interfacing techniques.[more]
Posted on 11 May 2008
The circuit detects a sudden shadow falling on the light-sensor and sounds the bleeper when this happens. The circuit will not respond to gradual changes in brightness to avoid false alarms. The bleeper sounds for only a short time to prevent the battery running flat. Normal lighting can be used, but the circuit will work best if a beam of light is arranged to fall on the light-sensor. Breaking this beam will then cause the bleeper to sound. The light sensor is an LDR (light-dependant resistor), this has a low resistance in bright light and a high resistance in dim light.[more]
