Digital Master Clock with 7 Seg LED Displays & Hourly Ch - Page 3 - Electronic Circuits Projects Diagrams Free

jatinder singh · 12th September 2006, 11:12 AM

Does the knowledge of PLCis necessary for seven segment LED display

Engineer SOSO · 7th December 2006, 09:57 AM

Hiiiiiiiiiiiiiiiiiii how r u all iam a new member here i wish all the members to be my friends . i am studying computer engineering this semester iam taking digital logic design and my instructor want a project from me which is digital clock and i saw the schematics that attached here but they are soo complicated and she wants a simple digital clock so if any one like to help me in this project because really i need it and i will be thankful for him

thanks a lot

mvs sarma · 8th December 2006, 05:15 PM

Hi Engineer SoSo

i can understand your condition. . when you get oppertunity to learn, really and sinerely do it. you may be comfortable in seeking help, as you used to seek as a child from parents. Now it is educatiuon for your brain to get trained and be able to take challenges in future. In the future , moment to moment who would help or spoon feed you-- sorry for this word-- just study with concentration and practice you will, i am sure excell in your academics and get ready for a higher education and even PHd whoknows?
please try to hardwork and practice the subjct my dear-- please don' get offended. there are, i am sure eminent personalities on this and sites like this. they could well solve or physically remove all your problems-- but is it REAL ??
all the best and look forward a brilliant expert in you

Sarma

Engineer SOSO · 10th December 2006, 05:07 AM

Hi mvs sarma

i want to tell you iam not the person who depends on others i try all the time to do every thing by my self . iam just saying that i need a help from who can and iam sorry for this word i dont need it from you . just this

thanks alot

audioguru · 14th December 2006, 12:26 AM

Quote:

Originally Posted by Engineer SOSO

my instructor want a project from me which is digital clock and i saw the schematics that attached here but they are soo complicated and she wants a simple digital clock

The clock circuit here is SIMPLE! It is a clock and a clock circuit is fairly complicated. It uses gates and counters and LED drivers. A watch uses one IC that does all that stuff.

Make a circuit that uses fewer parts, an LED Chaser maybe. Then tell your teacher that the blinking LED is counting and displaying the seconds.
http://www.electronics-lab.com/proje...003/index.html

Engineer SOSO · 14th December 2006, 03:07 AM

hi audioguru ,

thanks for the schematic that you posted , you helped me.

thanks alot

manoj.patil.1974 · 14th December 2006, 05:50 AM

How did you generate a time base using 32.768Khz ? I think you must have divided it till 1Hz ...
I am right now looking out to select an appropriate crystal frequency to generate either 50Hz or 60Hz accurately. any idea ?

Hero999 · 14th December 2006, 11:42 AM

You can do this with one IC, a CD4521 and a 4.194304MHz crystal will do.

oliverb · 11th February 2007, 09:34 AM

I have added a 1 sec electric clock motor drive pulse to this clock (taken from the 2sec ootput). This will drive quartz clcok motors and will sync them to the main display.

I have used this drive along with the 30sec pulse to drive a couple of large 12" dial clocks I have made.

The clock steps on 1/2min when the second hand hits 00 and 30 secs.

This drive can be used for adding calender, moonphase, tide etc displays to clocks.

The quartz clcok motors have their quartz driver cct cut out. The drive wires from the master clock connect direct onto the drive coil.
Brett.

oliverb · 12th February 2007, 02:43 PM

I have now built a larger bell unit. This is wired remote from the master clock and hidden in my hallway inside a real longcase clock with the chime turned off (1 less clock to wind).

I have used a large 4" longcase clock bell. The bell is struck by a Franch clock hammer attached to the armature of an old 30sec clock movement.

The bell is turned off at night from the switch in the master clock.

The chime is now fed from the 2sec output as the larger bell takes longer to ring out.

I have added a thermal fuse to the coil of the 30sec clock just in case it gets too hot.
Brett.

pasanrobotics · 20th February 2007, 01:36 AM

Quote:

Originally Posted by Hero999

You can do this with one IC, a CD4521 and a 4.194304MHz crystal will do.

Hey when segmets display 60 seconds, How do i reset it to zero?

Gayan Soyza · 20th February 2007, 02:55 AM

No need to reset the 4017. For every 10 pulses its reseting. If you want to reset to 9 pulses, simply you must reset the 9 th output in the 4017.Its easier if you take a decade counter for this like 4026.Specially designed for segments. Only needs the correct 1 second pulse.

pasanrobotics · 20th February 2007, 03:00 AM

Quote:

Originally Posted by Gayan Soyza

No need to reset the 4017. For every 10 pulses its reseting. If you want to reset to 9 pulses, simply you must reset the 9 th output in the 4017.Its easier if you take a decade counter for this like 4026.Specially designed for segments. Only needs the correct 1 second pulse.

Ah now I get it. Thanks

Gayan Soyza · 20th February 2007, 03:45 AM

I have a general question to ask. One second accurate pulse is a problem for many people, even for PIC’s. Can’t they build a crystal for 1Hz.or a small IC or a package which gives accurate 1 second. In analogues all the time we use pulse generators to get a pulse adding some more extra parts to the circuit. Why is this?? Any comments from you experts….

oliverb · 20th February 2007, 06:11 AM

This is how the display counts to and is set to zero at 60.

The 1 second pulse from (diagram 2) is connected to the input pin 1 of IC11. This IC counts from 1-0 and displays the seconds units via the LED display. When the count reaches 0 on the 10th pulse the IC resets and outputs a pulse to IC9 input pin 1. This advances the seconds tens display by 1. Every 10 seconds IC9 is stepped by 1 until the count reaches 60 seconds or 6 pulses to IC9. IC9 & 11 are reset by IC2d and IC12a. This reset also steps the Minute Units by 1 via the Set Secs switch not operated, IC7a and IC7b to IC8 input pin1.

You can find a full description of the whole circuit and all the diagrams om this web site. http://uk.geocities.com/brettoliver@...ctronic_1a.htm

Brett.

8th December 2006, 05:15 PM	(permalink)
mvs sarma Experienced Member	Hi Engineer SoSo i can understand your condition. . when you get oppertunity to learn, really and sinerely do it. you may be comfortable in seeking help, as you used to seek as a child from parents. Now it is educatiuon for your brain to get trained and be able to take challenges in future. In the future , moment to moment who would help or spoon feed you-- sorry for this word-- just study with concentration and practice you will, i am sure excell in your academics and get ready for a higher education and even PHd whoknows? please try to hardwork and practice the subjct my dear-- please don' get offended. there are, i am sure eminent personalities on this and sites like this. they could well solve or physically remove all your problems-- but is it REAL ?? all the best and look forward a brilliant expert in you Sarma __________________ Regards, Sarma.

14th December 2006, 05:50 AM	(permalink)
manoj.patil.1974 New Member	32.768Khz ?? How did you generate a time base using 32.768Khz ? I think you must have divided it till 1Hz ... I am right now looking out to select an appropriate crystal frequency to generate either 50Hz or 60Hz accurately. any idea ?

20th February 2007, 02:55 AM	(permalink)
Gayan Soyza Experienced Member Blog Entries: 1	No need to reset the 4017. For every 10 pulses its reseting. If you want to reset to 9 pulses, simply you must reset the 9 th output in the 4017.Its easier if you take a decade counter for this like 4026.Specially designed for segments. Only needs the correct 1 second pulse. __________________ Gayan Forum Supporter

20th February 2007, 03:45 AM	(permalink)
Gayan Soyza Experienced Member Blog Entries: 1	I have a general question to ask. One second accurate pulse is a problem for many people, even for PIC’s. Can’t they build a crystal for 1Hz.or a small IC or a package which gives accurate 1 second. In analogues all the time we use pulse generators to get a pulse adding some more extra parts to the circuit. Why is this?? Any comments from you experts…. __________________ Gayan Forum Supporter

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12th September 2006, 11:12 AM	(permalink)
jatinder singh New Member	Does the knowledge of PLCis necessary for seven segment LED display

7th December 2006, 09:57 AM	(permalink)
Engineer SOSO New Member	Hiiiiiiiiiiiiiiiiiii how r u all iam a new member here i wish all the members to be my friends . i am studying computer engineering this semester iam taking digital logic design and my instructor want a project from me which is digital clock and i saw the schematics that attached here but they are soo complicated and she wants a simple digital clock so if any one like to help me in this project because really i need it and i will be thankful for him thanks a lot

10th December 2006, 05:07 AM	(permalink)
Engineer SOSO New Member	Hi mvs sarma i want to tell you iam not the person who depends on others i try all the time to do every thing by my self . iam just saying that i need a help from who can and iam sorry for this word i dont need it from you . just this thanks alot

14th December 2006, 03:07 AM	(permalink)
Engineer SOSO New Member	hi audioguru , thanks for the schematic that you posted , you helped me. thanks alot

20th February 2007, 06:11 AM	(permalink)
oliverb Experienced Member	This is how the display counts to and is set to zero at 60. The 1 second pulse from (diagram 2) is connected to the input pin 1 of IC11. This IC counts from 1-0 and displays the seconds units via the LED display. When the count reaches 0 on the 10th pulse the IC resets and outputs a pulse to IC9 input pin 1. This advances the seconds tens display by 1. Every 10 seconds IC9 is stepped by 1 until the count reaches 60 seconds or 6 pulses to IC9. IC9 & 11 are reset by IC2d and IC12a. This reset also steps the Minute Units by 1 via the Set Secs switch not operated, IC7a and IC7b to IC8 input pin1. You can find a full description of the whole circuit and all the diagrams om this web site. http://uk.geocities.com/brettoliver@...ctronic_1a.htm Brett.