70 second clock very freaky

[flexx]

Dear all , please help me to built a very freaky circuit :

my circuit will be a watsch but not regular watsch , the regular watsch calculate the 1 minute equale 60 second , i want to built a circuit to calculate the 1 minute to 70 second .

please help me becouse i want to calculate the moon moving threw the earth .

:?::?::?::?:

 

[flatulent]

One method is to start with the usual 32 kHz crystal oscillator. First divide by 2^n to get the one second pulses. Then divide this by 70 go get your "minute" pulses. After that you can count in any way you want and decode the outputs to some display.

 

[flexx]

do you have a special circuit , and i can built it easily ?

can i control by NE555 by the pulse

 

[IanP]

You can use 555 to generate 0.1s square wave which then will be didvided by 700 using frequecy divider from the following site: **broken link removed**
This divider is a universal divider with which you can divide frequencis by up to 999 times. It is based on 7490 counters, so if you choose to build this circuit you will have gain some eeperience with clasic TTL stuff ..
Regards,
IanP

 

[echo47]

Move the moon through the earth?
Please don't do that. I'll spill my beer.

 

[flexx]

PLEASE HELP ME ,

this is too simple to made , just i want to change the time for 1minute = 60 sec to 1 minute = 70 sec

 

[VVV]

Use a microcontroller and you will divide down the frequency any way you like.
Can you be more specific, do you need a true minute, divided into 70 "seconds" or a "minute" consisting of 70 true seconds?
Either way, a micro will solve the problem easily and accurately. (PIC12Xxxx)

 

[flexx]

do you have the control circuit ? all i need the seconds turn in to 70 not 60 , and the minutes stil regular

1 hour = 60 Minute and every minute = 60 sec (regular)

1 hour = 60 minute and every second =70 sec
(this is what i want to do)

 

[VVV]

That is what I thought you wanted.
The schematic is really just a PIC12C508 for example. The code is the key. I will try something and then post it.

 

[VVV]

I finally got around to doing it. The schematic is very simple, just the micro and the crystal and some caps. The switch is not needed, unless you want to also produce real second pulses. There are two complementary outputs.
The code runs OK in the simulator.

 

[aldevan]

I make it using a microcontroller at89s8252, I make it only by software not RTC periferic used, by software when the count segund is 69 next clock is 00 and increment 1 minute, if you want it I can post, is in C language compiled with sdcc