Schematic for sinhron generator of 1 Hz

[cufta_bm]

Hello folks, i have small question/request if any 1 can help me with it.

i need schematic for sincron generator of f=1Hz which is compatible with electrical installation (230V , 50Hz). On output it has to have square signal , 0V and 5V.I have to use IC555 to build it.
(later i would as amble it)
I was trying to make something in OrCAD simulation just to se if it works so i can build it later , btu i cant make ti work. So if any 1 can help me with it.

1Hz sincrom generator with TTL signal, electrical schematic.

Thx alot.

 

[alec_t]

What on earth is a sinhron/sinhrom generator?

 

[cufta_bm]

sincron

generator of 1Hz that is sincron with electro-distributing network(230V, 50Hz), and i have to get square signal (0,5V).

 

[MrAl]

Hi,

You have to use a 555, why? Homework?

Ok, one way is to set the 555 up as a monostable, setting the pulse period for slightly less than 1 second but more than 1 second minus one line cycle (maybe half way between would be optimum), triggering it with a gated line frequency signal. Then, use the output of the monostable to lock out the input line frequency using the gate.
This means that the line frequency triggers the 555, but only when the pulse output is at a low logic level. This keeps the 555 sync'ed to the line frequency without using counters. This however does assume that the 555 can be set up accurately enough to be accurate to 1 second plus or minus one half line cycle time (1/100 second for a 50Hz line). It also has to be able to maintain that accuracy over time. Since that's about 1 percent, the 555 might just do it, but i would rather use counters myself.

 

[cufta_bm]

yea it my homework assignment . i got a "tip" from my professor, he suggested that i use 3x IC (it doesn't have to bi like that, it was just a suggestion from him).
how would you do it with counters?

 

[ericgibbs]

sincron

generator of 1Hz that is sincron with electro-distributing network(230V, 50Hz), and i have to get square signal (0,5V).

hi,
The way I read your project.?

Are you asking for a 1Hz square wave thats derived from a Mains 230V 50Hz supply?
If so, use a low voltage mains step down transformer, say 230V/6Vac. The 6Vac output from the transformer into a LM393 comparator, via limiting resistors.
The LM393 would act as a zero crossing detector, if the LM393 output pull up resistor was connected to +5V the output would be a 50Hz square wave at TTL levels.

Use the divide by 5 section of a 74LS90 to give 10Hz, followed by another 74LS90 set as a divide by 10.. output would be 1Hz.

If you must use a 555 somewhere, use it for the zero crossing detector in place of the LM393

 

[cufta_bm]

hey Ericgibbs, any chance you can draw me a schematic?
I have found an old transformer, its from my old mobile phone. so i have DC 5v power supply, now i need schematic for how to change frequency.

 

[KMoffett]

**broken link removed**

Ken

 

[cufta_bm]

cheers, thx

 

[MrAl]

Hi,

Just one additional thought to add here...

Depending on what you intend to use this pulse for you may find that it is not nearly as accurate as you first though, depending on what country you live in. In the USA for example, there is supposedly a change going on that makes the line frequency less accurate than it was say 2 years ago. That's because they decided not to adhere to a strict time base anymore and rather go in favor of a more efficiently run power grid. I dont like this idea either but it may be a necessary evil in the modern world we live in.
In any case, clocks that use a line sync'd time base can be off by as much as 12 seconds per month or something like that. So depending on what it's being used for, i might tend to want to go with a crystal based oscillator instead of a line sync'd circuit. If it's for homework, you may want to remind the instructor that changes like this mean a less accurate clock signal, whereas before this change the long term clock signal was very very hard to beat rivaling good crystal oscillators over the long term.

 

[cufta_bm]

Can any 1 drow me an electrical schematic for these?

 

[KMoffett]

T1 does not have to be a separate transformer, but can be part of the 5VDC supply.

Ken

 

[cufta_bm]

Ty for that. i just have 1 question , request.

How sure are you it works, because i still get 50Hz on COUT.
I wanted to test that in electronic workbench 11 , but seams i cant find CD4022 and CD 4017.
Any chance you can help me with that?

 

[KMoffett]

Ty for that. i just have 1 question , request.

How sure are you it works, because i still get 50Hz on COUT.

I've used it in the past. Re-check you wiring.

I wanted to test that in electronic workbench 11 , but seams i cant find CD4022 and CD 4017.
Any chance you can help me with that?

Can't help with simulators.

Ken

 

[cufta_bm]

Can i ask you for 1 last thing? I still cant get 1Hz signal. And i cant figure what im doing wrong. So any chance you can drow these schematic with actual physical connection as it has to be with these legs.

these is how i did it
View attachment 60685

And 1 more thin, how much volt is that square signal you get. is it 0V and 5V ?

 

[cufta_bm]

i was finely able today to use oscillator. And first thing i noticed was that i have 0.76V on base]. So my 2N3904 is closed. I will tray to lover voltage that cams on base under 0.7V so my transistor becomes open. What do you think, cud that work?

Problem was i didnt have any current on transistor collector so i had no power on Vdd.

 

[cufta_bm]

Seams i cant get any current from C on transistor.Do i need to have Ube>=0.6V to get 5V on collector? Can i use C from transistor to power my 4022 and 4017?
Or do i have to get 5V from graetz ?

Can you pliz help make it work.. if you can make detailed el schematic of that.

 

[KMoffett]

"Or do i have to get 5V from graetz ?" What is "graetz"? The +5V for the IC's is the same +5V for the transistor. With no 50Hz input signal, the base on the 2N3904 should be at 0.0V. With a 50HZ AC (bipolar) input the base volt should be a pulsating DC voltage going between 0.0V and ~0.6V. You would need an oscilloscope to see that. With an averaging DC multimeter you would likely read ~+0.3v. With +5V on the collector's load resistor, you should see +5v on the collector with no input signal, and an averaged of about +2.5V on a DC multimeter with a 50Hz AC input signal.

Ken

 

[cufta_bm]

these is Graets ... don't know how you call it in English.
https://hr.wikipedia.org/wiki/Datoteka:Graetz.jpg

did you soo how i connected everything? On the picture i posted up there. So if you can say if its ok or not.
My teacher also told me its not good and that it wont work and that i have to figure it out why docent work.

 

[KMoffett]

these is Graets ... don't know how you call it in English.
https://hr.wikipedia.org/wiki/Datoteka:Graetz.jpg

We would call Graets a "bridge rectifier".

did you soo how i connected everything? On the picture i posted up there. So if you can say if its ok or not.
My teacher also told me its not good and that it wont work and that i have to figure it out why docent work.

You do not show a +5V supply connected to #16 pins of the ICs, or the top of the collector load resistor.

Ken