Counters and repeating timer... help needed !

[yusuf]

Hello Friends ;

Friends, I have a repeating timer ... I have attached in my attachment.. please have a look !


And i want :

I want that this repeating timer to run for only four time because at running 24hr's a day the
time period will not be precise...

SO I want to run this repeating timer at least four times , and after four timer it
should turn off and stay turn off for 1 hr... and after 1hr it should starts to run again..
up till four time...
And this repeats...

As I am new in electronics field ...... but I hope we will need counter and Oscillators..
For 1hr timer we can use Cd4060 and we can also use as counter to sense 4th pulse...

eg : 1 , 2 , 3 , 4 (from repeating timer) and after running four time the repeating timer
will become off and cd4060 timer will start to run for 1hr...

It just a guess... as I am new so ....

Friends I need your help's and suggestions to complete this !

Thanks

 

[alec_t]

The circuit you have attached won't work. It oscillates at ~2.5MHz ....much too fast to drive a relay. Why don't you use the conventional single-gate oscillator?

 

[yusuf]

I HAVE SET R1 : 1mega ohms and R2 :3mega ohms. I am getting 10 minutes on and 30 minutes off time successfully.. And the relay is also working good.

 

[alec_t]

In that case what you have built isn't exactly the same as what you have drawn in your schematic ;-)

I love Knowledge !!!! very much.....

Yusuf, with all the help you have already been given on your other timer projects you should have gained enough knowledge to work out for yourself how to make a 1 hour timer and how to count up to 4. Use that knowledge to advantage in this new project.

 

[yusuf]

I have made 1hr timer with CD4060 sucessfully alec.. But how do i join to my repeating timer friend..

 

[alec_t]

If your repeating timer is giving 10 mins on and 30 mins off then its period is 40 mins. You can't run it four times in one hour!

 

[yusuf]

I dont want to run it four times in one hour.. I hope you haven't understood what I mean..
Again... I want the repeating timer to run only four times.. And after running four times it should become off for 1hr(cd4060 timer). And after 1hr the repeating timer should again run for four times.. And this repeats..

 

[alec_t]

I want that this repeating timer to run for only four time because at running 24hr's a day the
time period will not be precise...

However you run it the period will not be precise, because of the form of oscillator you are using. A 470uF capacitor has a leakage current comparable to the current you are using to charge it (via the 1meg resistor etc), and that leakage current will vary with temperature and with aging of the cap. For precise timing you need a crystal-controlled oscillator feeding a counter.

 

[yusuf]

However you run it the period will not be precise, because of the form of oscillator you are using. A 470uF capacitor has a leakage current comparable to the current you are using to charge it (via the 1meg resistor etc), and that leakage current will vary with temperature and with aging of the cap. For precise timing you need a crystal-controlled oscillator feeding a counter.

I am using 470uf non-polarize capacitor's and it is working good .... I am getting very close to precise time...

If possible can you provide me a crystal-controlled oscillator feeding a counter.....
so that I can deep study on it..

 

[ronv]

These make me an absolute believer in evolution.

 

[alec_t]

I am using 470uf non-polarize capacitor's and it is working good .... I am getting very close to precise time...

Well if that's 'precise' enough for you use it ;-), but in that case I don't understand why you think switching it off for 1hr after a 2hr:40min run will make it any more precise?

If possible can you provide me a crystal-controlled oscillator feeding a counter.....
so that I can deep study on it..

Try googling for 'crystal-controlled oscillator'. There must be lots of examples on the net.

 

[yusuf]

but in that case I don't understand why you think switching it off for 1hr after a 2hr:40min run will make it any more precise?

it's precision changes to some minutes in 24hr's...

But I want to switch off the repeating timer for 1hr after running four times because I want to switch the led..
And I want to make this project for further knowledge !
Please help friends?

Thanks

 

[alec_t]

it's precision changes to some minutes in 24hr's...

Sorry, you've lost me ;-(

But I want to switch off the repeating timer for 1hr after running four times because I want to switch the led..

Surely you don't need to stop the timer just to switch on a LED?

And I want to make this project for further knowledge !

You should certainly have learned something by the time you complete this project.