controlling circuits with an actual clock.

[JonathanAnon]

Hi guys, I'm working on something that I want to trigger at a particular time.. I was gonna just open a clock and tap off a part of the alarm to trigger a transistor/relay .. but what do people normally do?

I want to just have a relay click on at 8am which kicks my kettle on.

[budm]

Re: controlling circuits with an actual clock.

Using something like this?
http://growace.com/24-hour-programma...FUQ6QgodC0QA8A

http://www.amazon.com/s/?ie=UTF8&key...l_10hetq9muz_b

[JonathanAnon]

Re: controlling circuits with an actual clock.

Hey Bud, I have a circuit built at the moment based on a 555 timer. I have this triggering a transistor which triggers a 240V (Ireland AC) relay. So I'm toying with ideas of what I could do with a mains voltage devices using a circuit based on a realtime clock (not the oscillation that the 555 provides).

I put a search in my provider's site and I get a load of ICs...

http://radionics.rs-online.com/web/c...view-type=List

Could I use one of these chips, and attach some sort of display? How does it work?

[Rob Northen]

Re: controlling circuits with an actual clock.

I have used the Dallas DS3231 chip in a few projects, and it is really keeps precise time, even over longer period

[JonathanAnon]

Re: controlling circuits with an actual clock.

I have used the Dallas DS3231 chip in a few projects, and it is really keeps precise time, even over longer period

I'll check it out, thanks Rob..

[ben7]

Re: controlling circuits with an actual clock.

I believe there are some RTC chips that have a programmable timer output. You'd have to use an arduino or the like to write to the registers in the RTC chip.

Or else you can use a programmable divider chip, and use a crystal as the main clock source. For example, dividing a 10Hz wave by two will give you a 5Hz wave. Some digital clocks that plug in to the wall use the mains frequency as a timebase, it actually works fairly well - divide the 50Hz by 50 and you get 1Hz, or once per second

[JoeyJoe]

Re: controlling circuits with an actual clock.

You should defiantly get an Arduino. So much fun if your into electronics. Get a RTC module too (or the parts to make one).

[eccerr0r]

Re: controlling circuits with an actual clock.

Is this what's wanted?

heh. Sorry, that's what I thought when people post a topic like this...

[JonathanAnon]

Re: controlling circuits with an actual clock.

Yeah it's hard not to just ask for the above, as it's probably the best description of the function of the circuit I'm looking for... But I didnt want red flags popping up all over the place though, and the Gardaí arriving at my house with a SWAT team..