A Newcomer (Digital Clock) - Electronic Circuits Projects Diagrams Free

Digimaniac · 22nd March 2004, 06:34 PM

Hi Guys and Girls,
I am so glad to find such forum on the internet after about 4 days searching so I wish you can help me here.
First , I wannna inform you that I am a Student in The Faculty of Engineering here in Egypt but I have my own works too , So that's my first try to make my first Electronic Device, so forgive my unconscious mistakes in writing this topic.
Now I am trying to make a Digital clock using 555 to make a pulse , 7490 as a counter ,7447 as a BCD Decoder and a 7 segment displays.
Now I managed to make a units of the seconds I mean by the units the 0-9 part and went to make the tens part (0-5) but here is the problem as I can't force the 7490 to work as a 6 decade counter so please inform me on how to do with it and if you got any idea of R91,R92,R01 and R02 please tell me about them As I think that the problem is in joining those pins , Yours Aly

elec_lover · 22nd March 2004, 07:11 PM

It is hard to build a clock with basic components, look at Sams clock: http://users.otenet.gr/~athsam/samgordon_clock_eng.htm

Digimaniac · 23rd March 2004, 01:16 PM

Hi Guys,
I finally managed to make the 74ls90 work as a 6 decade counter (0-5) and if anyone wants to know the way just ask about it and I'll be so glad to answer.
Yours, Digimanic

ljcox · 27th March 2004, 02:39 AM

Quote:

Originally Posted by Digimaniac

Hi Guys,
I finally managed to make the 74ls90 work as a 6 decade counter (0-5) and if anyone wants to know the way just ask about it and I'll be so glad to answer.
Yours, Digimanic

A counter that counts from 0 to 5 is not a decade counter. It is a Modulo 6 counter. A decade counter is a Modulo 10 counter.

If you search my posts, you will find some Modulo 6 counters in answer to Alex (johnsoax) See the posts dated Mar 10 and Mar 12.

Len

renren1227 · 23rd November 2006, 10:33 AM

could you please make a diagram on digital clock... i really need it

RODALCO · 23rd November 2006, 05:44 PM

http://www.google.co.nz/search?q=TTL...&start=40&sa=N

Try above link which has a simple TTL counter with a schema.

Hope it works

RODALCO · 28th November 2006, 08:03 AM

renren1227 I have just posted a thread with a complete TTL clock schema.

Digimaniac The R0¹ and RO² can be linked together for the normal clock applications same for the R9¹ and R9² terminals.

You leave these separated when a 24 counter without a 7400 is needed. For example: and can be wired by connecting the R0¹ from the hours and ten hours to the Q2 output from the 10 hour decoder.
Then the R0² from the hours and ten hours have to be connected to Q3 from the hour decoder.
The R9¹² can be bonded together to the negative rail.

anthony123 · 15th October 2007, 05:26 PM

hi guys.... i'am in the same proyects.. somebody can helpme?? Some people told me that i cant use the house electric line that contains a 60 Hz...
I hope some anwers...thank.. and sorry for may bad english, i'am a spanish talker...

Cry_Wolf · 18th October 2007, 12:43 AM

well you can use the 60 Hz house electric line. I hope all u need for your project from the line is DC 5 or 12 Volts

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22nd March 2004, 06:34 PM	(permalink)
Digimaniac	A Newcomer (Digital Clock) Hi Guys and Girls, I am so glad to find such forum on the internet after about 4 days searching so I wish you can help me here. First , I wannna inform you that I am a Student in The Faculty of Engineering here in Egypt but I have my own works too , So that's my first try to make my first Electronic Device, so forgive my unconscious mistakes in writing this topic. Now I am trying to make a Digital clock using 555 to make a pulse , 7490 as a counter ,7447 as a BCD Decoder and a 7 segment displays. Now I managed to make a units of the seconds I mean by the units the 0-9 part and went to make the tens part (0-5) but here is the problem as I can't force the 7490 to work as a 6 decade counter so please inform me on how to do with it and if you got any idea of R91,R92,R01 and R02 please tell me about them As I think that the problem is in joining those pins , Yours Aly __________________ Alilo

22nd March 2004, 07:11 PM	(permalink)
elec_lover	It is hard to build a clock with basic components, look at Sams clock: http://users.otenet.gr/~athsam/samgordon_clock_eng.htm

23rd March 2004, 01:16 PM	(permalink)
Digimaniac	Secceeded Hi Guys, I finally managed to make the 74ls90 work as a 6 decade counter (0-5) and if anyone wants to know the way just ask about it and I'll be so glad to answer. Yours, Digimanic __________________ Alilo

23rd November 2006, 10:33 AM	(permalink)
renren1227	could you please make a diagram on digital clock... i really need it

23rd November 2006, 05:44 PM	(permalink)
RODALCO	http://www.google.co.nz/search?q=TTL...&start=40&sa=N Try above link which has a simple TTL counter with a schema. Hope it works __________________ There are more ways to get to Rome. Electricity, Electric clocks, Meters and Trains are great. Last edited by RODALCO; 23rd November 2006 at 05:51 PM.

28th November 2006, 08:03 AM	(permalink)
RODALCO	renren1227 I have just posted a thread with a complete TTL clock schema. Digimaniac The R0¹ and RO² can be linked together for the normal clock applications same for the R9¹ and R9² terminals. You leave these separated when a 24 counter without a 7400 is needed. For example: and can be wired by connecting the R0¹ from the hours and ten hours to the Q2 output from the 10 hour decoder. Then the R0² from the hours and ten hours have to be connected to Q3 from the hour decoder. The R9¹² can be bonded together to the negative rail. __________________ There are more ways to get to Rome. Electricity, Electric clocks, Meters and Trains are great.

15th October 2007, 05:26 PM	(permalink)
anthony123	hi guys.... i'am in the same proyects.. somebody can helpme?? Some people told me that i cant use the house electric line that contains a 60 Hz... I hope some anwers...thank.. and sorry for may bad english, i'am a spanish talker...

18th October 2007, 12:43 AM	(permalink)
Cry_Wolf	well you can use the 60 Hz house electric line. I hope all u need for your project from the line is DC 5 or 12 Volts __________________ Khizer Naeem Mughal IIUI