# Need help in digital clock (hour, minute, and second) circuit

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by dj_ash1983, Oct 15, 2006.

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1. ### m3tasm_elzayatNew Member

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then if u dont mind give us ur diagram
i just strated in this project

2. ### pizzamixNew Member

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Hey, I have a school project for building a digital clock, and i have been using this thread as a reference. I was originally going to use 74161 counters, using their ENT and ENP leads to make them count to "59" correctly. After reading this, though, decade counters seem easier. My question is, can i use a 1Hz crystal oscillator circuit instead of the LM555? I have spent a few weeks in class building the oscillator using a 4060 chip and a 161 to limit the frequency to 1 Hz. Also, could someone post the full schematic? =(
I am using Electronics Workbench to plan out the schematic, but my school only has the 1996 version, and it seems a bit outdated. The seven segment displays on EW are hard to understand (for me anyway) and i am having trouble replicating this circuit. Any help will be appreciated! Thanks!

3. ### m3tasm_elzayatNew Member

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i also already finshed my digital clock project except pulse generator and Temporarily use ic 555 i asked my prof, he tell me the output pulse of 555 my be shanged more than or less 1 hz coz of rising temp of the ic , crystal oscillator is sutable but the problem in dividing the frequancy , also dividing the AC voltage of frequang 60 HZ not good idea

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5. ### Wond3rboyMember

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Ending finally!

Hi i was helping a junior of mine on the same subject and i stumbled upon this great PDF. Its uses 6 counter IC's(7490) and is very nice if you see how it works and all.It shows the versatality of 7490 for use a multi mod counter.

#### Attached Files:

• ###### digitalclk.pdf
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6. ### logoleafNew Member

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Need to finish project

Hello everyone. I'm new here and looking for a real help. I know that it's kinda freak me out to ask people for a diagram but time is running out for me. I have to turn in my project on 5/13/09. I've been sitting around to draw a diagram to make it works but, unfortunately got no luck. Now asking for dj_ash1983 to post a diagram. So, i can have it put together in 2 days. I would either turn in project or get 00 points. So, please help by post a diagram here or send it to <snip>. Any help or suggestion would be really appreciated because i'm out of thinking. Thanks in advance guys.

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7. ### HarkeNew Member

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Help

You can make minute hand as the same way what you have done for the second hand.To make twelve hour digital clock is very difficult task since after twelve we have to set it to 01.

8. ### mnearyNew Member

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Are you answering the 2006, 2008, or 2009 part of the thread?

9. ### ramiliNew Member

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Hi everybody! I'm doing the same project, I was reading the pdf file you attached about the digital clock, so I understand that second and minute part look the same, and when the the ten digit become 6 I have to reset the whole thing which I think they already did, and connect the output of the second part to the clock of the minute part, here is my question what is this output, what pin number of the second part has to be connected the the minute part? please give me the exact pin number, I'm getting a little bit confused! Thanks

10. ### jovelllNew Member

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I'm currently making a 12 hours clock..can you give me an advice as to how to make it 12 hours..I'm really having a hard time with it..I'm done with minutes and seconds..pls do help me..

11. ### arvinpaul_juareNew Member

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hi, can i have the circuit of this digital clock...i tried many times but until now it doesn't have any display

12. ### james2554New Member

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Hours,mins and second project nedd help!!

Can anyone show me a schematic of a 24 hour clock that counts hours,mins and secs using 74hct161 chips thanks

13. ### bledzaNew Member

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please i nid the same data as asamaster on digital clock display circuit my email is <snip>

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14. ### mazaismoNew Member

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please i want a full schematic diagram of a 24-hour digital clock circuit using 7490 as main ic or any ic , i really need it badly....my email is
<snip> thanks

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We are already finished making d clock. But the problem is how to design the hours so that after reaching 11:59, it will go back to 01 instead of 00. Anyone can help?

16. ### leocheongNew Member

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Please!!! I want a full schematic diagram of a 24-hour digital clock circuit, and it's about used only pulse generator (analog circuit using LM555), decade counters (74LS90), BCD decoders (74LS47), AND Gate ICs (74LS08), and 7-segment LEDs.

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17. ### emem118New Member

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may i ask you,what is the value of the capacitor and resistor??i really appreciate your reply as soon as possible.thanks.

18. ### romzkidNew Member

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that's also my problem... i cant find a way to make up for my hour using 74LS192

19. ### nhepNew Member

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hey man can you give me a schematic diagram pls.i need help in my project,digital alarm clock,with ic 7447 and 7493 if im not mistaken 7493 and 7490 is the same?

20. ### AnalogKidWell-Known Member

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This thread is almost three years old.

ak

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