Strange digital clock dilemma

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Deleted member 115935

Joined Dec 31, 1969
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There are no plugs or sockets but the boards are connected with wires
You have items marked and look like plugs / sockets on the schematics,
you say these a wires ?
can you share how these are wired together please as this is fundamental to understanding the design,
 

Deleted member 115935

Joined Dec 31, 1969
0
This is my paranoia but I think maybe the ground of the electricity is isolated from Earth ground creating a voltage potential or some kind of spiritual potential even with the pipes of the building. If this is the case I have to use my reasoning to resolve the problem and then when I resolve the problem mentally a transfiguration will occur and maybe the clock will start functioning properly instead of blindly adding bypass capacitors because none of us know the problem for SURE. I really don't want to do anything in haste. If you choose to ignore me I don't blame you.
what is a " spiritual potential " please.
 

Deleted member 115935

Joined Dec 31, 1969
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What if I fused both 0.1 UF capacitors to ground instead of using one fuse for both, would it be safe then? I am worried about a neutral to live side short through both capacitor of the 12V power supply.
Why do you have capacitors on the mains to ground ?
why do you have you a fuse on the capacitors ?
why do you no have a fuse on the main input ?
 

Thread Starter

Arjune

Joined Jan 6, 2018
176
I'm sorry about the mistake of the power supply but I think the reason I was incorrect and confused is because they're using black magic on me probably. I will now try to upload the schematic of the power supply, the external 12V power supply right now but I had a problem finding the folder that has the schematic on my tablet. I'm worried that the 0.1uF 200 volt capacitors could short because of line Spike voltages so I think I need a fuse on each capacitor. There is a fuse going to the 10 ohm resistor of the transformers primary. There is a 0.5 amp fuse also going to the input of the 5.6V regulator on the clock box and there is a coaxial jack on the box for that input.

clockpwr.png
 
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Thread Starter

Arjune

Joined Jan 6, 2018
176
You have items marked and look like plugs / sockets on the schematics,
you say these a wires ?
can you share how these are wired together please as this is fundamental to understanding the design,
I don't think there's any confusion it's just that I didn't add plugs and sockets but that the wires are soldered to the boards without plugs and sockets. What I didn't have is where the am/pm indicator input goes. The am/pm indicator inputs of the diodes of the AND gate (on the clock extras board) go to logic output 2 of the units cd4510 counter and logic output 1 of the tens counter of the modulus 12 counter. Although I'm not sure because I'm having trouble thinking of how I wired it.
 

Sid723

Joined Oct 9, 2015
11
You really should remove both 0.1uF caps and 0.5amp fuse going to the ground pin. Ground should only be used for safety by wiring it to the case of the equipment. If the equipment case is metal. Otherwise ground does not need to connect to anything.

Sid
 

Thread Starter

Arjune

Joined Jan 6, 2018
176
The fuse belongs in series with the Line. This is for your safety. Please never fuse a ground.
Dick, you mean that if the ground was lifted somehow then there would be danger - I don't see your logic. I plan to use two fuses for each of the two capacitors going to ground if there's a surge. If ground was disconnected through the fuses there wouldn't be a hot level to the chassis. Am I right?
 

AnalogKid

Joined Aug 1, 2013
9,498
If ground was disconnected through the fuses there wouldn't be a hot level to the chassis. Am I right?
No.

You are completely wrong. If the ground is disconnected with the line still connected, the circuit is lethal. This is because parts of the circuit that were at ground potential now are at line potential.

ak
 

Deleted member 115935

Joined Dec 31, 1969
0
I'm sorry about the mistake of the power supply but I think the reason I was incorrect and confused is because they're using black magic on me probably. I will now try to upload the schematic of the power supply, the external 12V power supply right now but I had a problem finding the folder that has the schematic on my tablet. I'm worried that the 0.1uF 200 volt capacitors could short because of line Spike voltages so I think I need a fuse on each capacitor. There is a fuse going to the 10 ohm resistor of the transformers primary. There is a 0.5 amp fuse also going to the input of the 5.6V regulator on the clock box and there is a coaxial jack on the box for that input.

View attachment 247109

one bit at a time,
why do you have the 0.1 uF capacitors ?
are they rated as safety capacitors ( i.e ones designed to go across mains )
A standard 200 V capacitor is not good enough for such a situation
But still dont know why you have them.

as for a fuse on a capacitor , on the ground side ?
so if the fuse blows, the capacitors are now floating at the live rail,

A very disasterous condition,



Second the 10 ohm resistor ,
Why ?
All its doing is consuming power,


And please

"black magic" is an insult to a large part of the community,
it is NOT acceptable language.

In general, you are mentioning "mystic" inputs to your design in many places,
there si no mystic, magic , out side forces in any of this design,
and certainly not in the help you are receiving.

You have also side stepped how the different schematics are connected,
what pin goes to what , without such full information, we have no information,
 

Deleted member 115935

Joined Dec 31, 1969
0
I don't think there's any confusion it's just that I didn't add plugs and sockets but that the wires are soldered to the boards without plugs and sockets. What I didn't have is where the am/pm indicator input goes. The am/pm indicator inputs of the diodes of the AND gate (on the clock extras board) go to logic output 2 of the units cd4510 counter and logic output 1 of the tens counter of the modulus 12 counter. Although I'm not sure because I'm having trouble thinking of how I wired it.

" Although I'm not sure because I'm having trouble thinking of how I wired it. "

that s the point,
unless we know how the circuits are connected, we know nothing,
 

Thread Starter

Arjune

Joined Jan 6, 2018
176
I assume we have common knowledge and you would know how the boards are connected andrewmm. The schematics are intricate and it would be difficult to trace. It seems that you're offended if I appear to be a teacher but I'm willing to learn from you all, you should do the same. I have the 0.1uF capacitors because there appears to be an anomaly that has to be suppressed that is unknown and you all have failed to identify what that is. The 10 ohm resistor is to suppress large current spikes in conjunction with the capacitor to neutral and it eases the inductance load of the transformer at startup which may have caused sporadic operation of the clock. The capacitors are not safety capacitors because I don't have them. I put two fuses on the two capacitors to ground instead of one fuse for both and I don't see any danger that would be happening if the capacitors were to short. The fuses would blow and no high voltage would go to the chassis - I have an aluminum chassis.
 

Thread Starter

Arjune

Joined Jan 6, 2018
176
The updated wiring and schematic is attached of the power supply capacitors to ground which uses two fuses, one for each capacitor.
 

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Deleted member 115935

Joined Dec 31, 1969
0
I assume we have common knowledge and you would know how the boards are connected andrewmm. The schematics are intricate and it would be difficult to trace. It seems that you're offended if I appear to be a teacher but I'm willing to learn from you all, you should do the same. I have the 0.1uF capacitors because there appears to be an anomaly that has to be suppressed that is unknown and you all have failed to identify what that is. The 10 ohm resistor is to suppress large current spikes in conjunction with the capacitor to neutral and it eases the inductance load of the transformer at startup which may have caused sporadic operation of the clock. The capacitors are not safety capacitors because I don't have them. I put two fuses on the two capacitors to ground instead of one fuse for both and I don't see any danger that would be happening if the capacitors were to short. The fuses would blow and no high voltage would go to the chassis - I have an aluminum chassis.

Thank you


My level of knowledge is undoubtable different to yours, not least I think Im a lot older than you , by a factor of two or three

Unfortunately, I am not able to guess how the wires are connected between the schematics,
and without that information, they are just isolated bits of circuits, and we can comment no further on that.

As for learning,
a very wise person many years ago said something on the lines of the day I stop learning is when I die,
and I think Im still alive,

As for , am I willing to learn from a teacher
of course I am, I learn from my students as well as the professors all the time,
could you highlight what your speciality is in please.

As you are on the forums , and asking for electronic answers, I assume you also are open to learning,

You say words to effect of there is an anomaly that we have all failed to identify , and these capacitors are the solution.
This makes no sense to me,
I have seen no reference to what anomaly occurs without these capacitors in this forum post.

Have you been on this clock circuit for a while,
I gather you have posted in many posts,
so may be you are suffering "the great whisper". if you ask enough experts partial question, you will get every possible contradicting answer.

May be , a post with the complete information in it would be helpful there.


The 10 ohm resistor on the transformer,
How did you arrive at 10 ohms, what tests were you doing to check this ?

did you try say 75 Ohms, or 5 ohms, to see what was the best result,
What was the clock problems you were having , how did you reproduce them ?

How did you come to the idea of a resistor on the transformer ?
was it a forum post ?

What the resistor is doing is only loosing power.

At start up , the initial edge of the mains applied across an inductor is an instantaneous edge,
current in an inductor is inverse to the frequency, an vertical edge has infinite speed,
so the initial current into a transformer is "near zero"

You might have seen start up problems
this is quiet normal for digital circuits,
at start up, till all the voltages are stable, the actions of a digital circuit is "out side of the data sheets"

The standard answer , is to have a power up reset circuit,

This holds all the digital parts in a fixed state till the power is stable, then releases the digital circuits

I understand you have a battery back up circuit,
but the pictures I have seen,
as the power is removed / connected, this circuit will connect the leds to the battery,
the battery will at this point at best drop its voltage , probably such that the digits stops working,
or even to point that the volts dis appears to the digits , or some of,

The answer to this is to have a proper switch over circuit,
I seem to remember the answer was to simply move the hold up capacitor you have to the other side of the diode.

A fuse to ground , is never a good idea.
The reason for a fuse, is to disconnect the live from the circuit on a fault.
The way you are showing them, if the fuse does blow, the circuit will just carry on working,
so how would you know there has been a problem ?

Put the fuse on the live input to the circuit,

As for the capacitors,
If you were driving a car that needed petrol, and you could only get diesel,
would you put the diesel in ?
Its the same for safety capacitors,
they are designed and rated for the job, and fail "open"
and do not explode during a fault
Using the wrong type is about the most dangerous thing you can do ,

If the chasie is earthed, then with the fuse in the line as I indicate above,
then in case of problem, the current goes to the case, yes, but the case being earth, the fuse blows.
and the volts on the case are always "zero"

Good luck with this

I very much applaud your efforts,
you are evidently very good at self learning,
it would have been so easy for you to just purchase a clock, or even copy an on line circuit,
but you have managed where many other shave failed

I would sugegest that you review your style of your schematic diagram,
Have a look at other diagrams on line,
I say this , as we "engineers" get used ot reading a schematic in a certain way
we expect things to flow left to right
we expect connectors on the edges of the page
we expect notes as to where each connector goes to
we expect txt to be readble, not over lapping, and organised so its all readable from the same edge of the sheet.

Yes, its possible to read if the designer does not follow that system,
but like reading a book,
we expect all text to be the same sort of size,
In any language , we expect a certain set of punctuation, and usage of capitals,

Yee it possible to read stuff that's written differently
my kids used to write so each letter was a different colour !
and have you tried to read some of the auto translations.... that can be a challenge,
 

AnalogKid

Joined Aug 1, 2013
9,498
To teach is to learn twice. ~Joseph Joubert, Pensées, 1842

Who dares to teach must never cease to learn. ~John Cotton Dana

Whoever ceases to be a student has never been a student. - George Iles

ak
 

DickCappels

Joined Aug 21, 2008
7,989
If you are going to use capacitors from line to ground and neutral to ground, please use “Y” capacitors (as noted on their markings and their data sheets) and lower their capacitance so as to make ground leakage current less dangerous. I suggest 0.022 uf.

Have you tried any of the solutions suggested in this thread?
 

Thread Starter

Arjune

Joined Jan 6, 2018
176
I think I'm okay dick because the two ground capacitors are fused. I reasoned this this afternoon: Reflection, shadow, nervous system, and electricity are under slave control as slaves. Time was the slave to the slave so I better not change anything with the clock, the anomaly of changing time is for the best and I can always reset it. I'm sure with the difference of expectation I can learn something about my illness.
 
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