How to shield a live wire at 240V ?

[_q12x_]

I have a electronic board with leds (made by me) that is driving a relay. When that relay is closing it’s contacts, is actually switching the 240V for the light bulb switch in my room. This board is quite long, like 50cm (half a meter). The relay is in the left corner, and the live wires from it goes in behind the board to the hole in the wall for the mains switch. I also have a mild steel sheet behind my board that is grounded. It is shielding the interference of the 50Hz from the live wires from the wall to my sensitive circuit. But even If I have this grounded metal shield behind my board, the live wires from the relay are still affecting my entire circuit board, keeping it ON all the time. If I am disconecting the live wires from the relay, the board is functioning very well. Another IF, is if I disconnect the ground from the metal shield, the circuit board goes nuts. So the shield is doing it's job fine, but only for the live wires inside the wall !!! But not for the wires from the relay to the live switch.
- I want a way to shield these wires !
Thank you !

 

[marconi]

To check my understanding of your request- you wish for a short tick each time one of the 10 outputs of the LM3914 goes low to 0V? A tick not a buzz?

Do you obtain a tick sound now if you energise the buzzer? I guess this will be from the passive buzzer. Is there another tick when it is de-energised?

And if you energise the active buzzer it buzzes until de-energised?

 

[_q12x_]

To check my understanding of your request- you wish for a short tick each time one of the 10 outputs of the LM3914 goes low to 0V? A tick not a buzz?

Do you obtain a tick sound now if you energise the buzzer? I guess this will be from the passive buzzer. Is there another tick when it is de-energised?

And if you energise the active buzzer it buzzes until de-energised?

Yes, A single beep/tick. Not a long sound. Like a keypad from a telephone, the duration. Even shorter duration. Blip, and thats it. For each pin a blip. So it will be 10 consecutive blips when I activate fully from 1 to 10.
I didnt test anything yet. I might have to make an amplifier for that buzzer alone.
But please concentrate on how to make the connections first. I know is a bit contraintuitive but it is really what I need the most.

 

[stevethesparks]

I've always found these publications useful.

 

[DPG]

I've always found these publications useful.

I've got about 30 of the Babani range of books from many years ago. Good for basic reference and circuit ideas.

In fact I've got a well thumbed copy of How to Use Op Amps.

 

[_q12x_]

I've always found these publications useful.

I've got about 30 of the Babani range of books from many years ago. Good for basic reference and circuit ideas.

In fact I've got a well thumbed copy of How to Use Op Amps.

Thank you, I am a rookie in the experimentation/practical sector. I have already a ton of data/pdf's collected, also time I spent read all I could find about them and watched tons of video material from youtube. I have a good idea what they are and what can do. I have a very limited experience so far with them. I am still uncertain on using them, because i need greater and more profound experiments circuits, to be able to actually design with them. SO that is what im in search actually.
But everything you can give me (as pdf's) is well received. Again, the practice interesting and practical circuits is what im after and I lack experience. I best learn from practical use.

 

[marconi]

What I recommend is that you take your voltmeter set to dc and measure the voltage change on each of the output pins of the Lm3914 to find out what are the high and low states. And then draw a graph showing how each output changes with the proximity of your hand to the SCM.

Studying this graph you will discover that the outputs cannot be used directly to create a tick sound - another circuit is required between these outputs and the Tick Module TM. Or you might decide to include this circuit in the TM.

It will be the ten outputs which you will use to drive your tick module. The question is whether to use these outputs directly or to buffer them first in order that your tick module does not load and thereby disturb the brightness of the LEDs. I leave it to you to determine the best place to connect to the ten LM3914 outputs.

If you send me details of the two types of buzzer I will take a look at their specification.

 

[_q12x_]

I said already, that I plan to make a separate amplifier for the buzzer and the 10 inputs to it.
My biggest problem is how to wire it. That's it. Doesn't matter then, I will find a solution myself.
This sound thing is a distraction for both at this moment. I only put it in perspective.
At this moment I am playing with the transmitter and receiver boards. Im figure them out.

This is what I have.
I am not sure what is that DATA voltage. Im supplying them at 5V both on my breadboard. I put a led and 10k on the receiver DATA and when I touch with my finger the DATA from transmitter, the led turn on. Thats cool so far. Now I need a minimum and a maximum DATA voltages that I cant find anywhere. Hmmm. I assume is 5V. What you think?

Further: I put a 1M,then 100k ,then 10k between +5V and DATA and the led is only lit when the contact is made but it is immediately turned off. That suggest I need a variation on the DATA pin. Hmmm. That sucks a bit. To be able to mentain that led On all the time.

 

[stevethesparks]

I said already, that I plan to make a separate amplifier for the buzzer and the 10 inputs to it.
My biggest problem is how to wire it. That's it. Doesn't matter then, I will find a solution myself.
This sound thing is a distraction for both at this moment. I only put it in perspective.
At this moment I am playing with the transmitter and receiver boards. Im figure them out.

View attachment 64975
This is what I have.
I am not sure what is that DATA voltage. Im supplying them at 5V both on my breadboard. I put a led and 10k on the receiver DATA and when I touch with my finger the DATA from transmitter, the led turn on. Thats cool so far. Now I need a minimum and a maximum DATA voltages that I cant find anywhere. Hmmm. I assume is 5V. What you think?

Google AZ-delivery. You should find the information you require there.

 

[_q12x_]

I start to make the Remote Control test and with a little success.
I made a short movie(6min) in which I present what I did so far:

 

[DPG]

I said already, that I plan to make a separate amplifier for the buzzer and the 10 inputs to it.
My biggest problem is how to wire it. That's it. Doesn't matter then, I will find a solution myself.
This sound thing is a distraction for both at this moment. I only put it in perspective.
At this moment I am playing with the transmitter and receiver boards. Im figure them out.

View attachment 64975
This is what I have.
I am not sure what is that DATA voltage. Im supplying them at 5V both on my breadboard. I put a led and 10k on the receiver DATA and when I touch with my finger the DATA from transmitter, the led turn on. Thats cool so far. Now I need a minimum and a maximum DATA voltages that I cant find anywhere. Hmmm. I assume is 5V. What you think?

Further: I put a 1M,then 100k ,then 10k between +5V and DATA and the led is only lit when the contact is made but it is immediately turned off. That suggest I need a variation on the DATA pin. Hmmm. That sucks a bit. To be able to mentain that led On all the time.

I think those modules are for transmitting digital data over radio. So the data pin is not expecting a varying voltage or resistance, but actual 0s and 1s.

 

[_q12x_]

I think those modules are for transmitting digital data over radio. So the data pin is not expecting a varying voltage or resistance, but actual 0s and 1s.

I sincerely have no idea what those DATA pins supposed to do. If you can find me some good information about them, it will be nice. I think, in my opinion, if im adding a microphone to the DATA transmiter, on data receiver I will get the sound, analogue. And probably digital as well. I really have no clue. I only play around until I make it work.

 

[DPG]

I sincerely have no idea what those DATA pins supposed to do. If you can find me some good information about them, it will be nice. I think, in my opinion, if im adding a microphone to the DATA transmiter, on data receiver I will get the sound, analogue. And probably digital as well. I really have no clue. I only play around until I make it work.

Have you got a model number or any data for the modules? I don't think they are intended to work with audio signals.

 

[_q12x_]

Have you got a model number or any data for the modules? I don't think they are intended to work with audio signals.

This all the information I could grab from the ebay seller I buy from, and put it in this word document.

 

[marconi]

A little bit further forward.....

The same behaviour can be obtained with the hand.

By no means finished yet.

 

[DPG]

A little bit further forward.....

The same behaviour can be obtained with the hand.

By no means finished yet.

That is a great result. Looks nice and linear and stable.