Mains light-on indicator - Electronic Circuits Projects Diagrams Free

M.Joshi · 9th December 2003, 09:05 PM

Hi,

Could anyone tell me how I can design a mains light-on indicator to fit into the back of a standard light switch plate. I would like an L.E.D to flash every second and a beeping sound every 5 minutes while the mains light is on.

Thanks.

M.Joshi · 15th December 2003, 05:19 PM

Can anyone recommend a suitable I.C other than the 555 to generate the beeping sound every 5 minutes?

panic mode · 15th December 2003, 06:46 PM

You can use anything you like to generate delay and tone signal.
It doesn't have to be 555. Actually I don't really like 555 because
of pin arrangement. You can use TTL or CMOS chips...
Maybe you prefer bipolar transistors? Maybe UJT or PUT?
Or microcontroller?

M.Joshi · 17th December 2003, 09:52 PM

Hi,

Is it possibly to accurately generate a long delay with Bipolar transistors / UJT's?

Could you tell me where I could find information on how to generate long time delays using TTL / CMOS I.C's.

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

9th December 2003, 09:05 PM	(permalink)
M.Joshi	Mains light-on indicator Hi, Could anyone tell me how I can design a mains light-on indicator to fit into the back of a standard light switch plate. I would like an L.E.D to flash every second and a beeping sound every 5 minutes while the mains light is on. Thanks.

15th December 2003, 05:19 PM	(permalink)
M.Joshi	Timer Can anyone recommend a suitable I.C other than the 555 to generate the beeping sound every 5 minutes?

15th December 2003, 06:46 PM	(permalink)
panic mode	You can use anything you like to generate delay and tone signal. It doesn't have to be 555. Actually I don't really like 555 because of pin arrangement. You can use TTL or CMOS chips... Maybe you prefer bipolar transistors? Maybe UJT or PUT? Or microcontroller?

17th December 2003, 09:52 PM	(permalink)
M.Joshi	Bipolar Transistors / UJT Hi, Is it possibly to accurately generate a long delay with Bipolar transistors / UJT's? Could you tell me where I could find information on how to generate long time delays using TTL / CMOS I.C's.