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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 !
 
The receiver module, working just perfect from first built and try. Just excellent.
[ElectriciansForums.net] How to shield a live wire at 240V ?


And now the transmitter with 2x555's. You can see those small pads there. So hard to make and place them. So hard.
[ElectriciansForums.net] How to shield a live wire at 240V ?
 
Thank you ! Though is a bit too overwhelming hard and the little pads, with way too many problems. But the good news is, it can be built like that as well. Hard but possible.
You can see in the right side some black marks, is because the solder does not stick after awhile. Problems. But it seems ok so far. It is not my first smd IC that i worked with, but is a first with all the pads mounted. What a hell. And I have a second one to make as well.
This one is clearly a test as you can see it sits by it's own. I can easily integrate it on the main circuit board now that has all its pads.
If you zoom in the image you can read its a 555. Heh.
[ElectriciansForums.net] How to shield a live wire at 240V ?
 
I remember visiting a US electronics manufacturer called Allied Signal and being astonished by the automated line which produced circuit boards, inspected and tested them and then sent them off for environmental stress testing - without any human hands touching the boards.

Here is a youtube clip of another firm's production line which I thought you'd enjoy watching.


The printed circuit boards in the equipment I am familiar with were multilayer boards in order to make all the necessary connections, so crammed were the the boards with ics. Quite how this was achieved I must one day look up. I know they cost hundreds or more £ pounds each. Costing so much they were often repaired where possible to do so.
 
Thank you for the video, very nice and I watched a couple of similar ones in the past. I know about their real existence and how cool they are.
So, mister @marconi I am in need of your assistance. If you can, of course.
It is a side project but is still important to get it rolling. I mentioned I have a pickit2 ready and 10pcs of PIC 12f508.
I stay like 14h to figure out how to install all the necessary software for pickit2 and to actually see the pickit2 listed as normal option to select, because it was gray out and I could not select it as an option. In MPLAB :
[ElectriciansForums.net] How to shield a live wire at 240V ?

Again, I did this thing in the past, and programmed some 16f84A and some others, but not many.
Now that my pickit2 is alive, all I need is the correct stuff to send to it and to it's 12f508 that I installed on a "pickit2 DemoBoard" exactly like this one:

[ElectriciansForums.net] How to shield a live wire at 240V ?

Please tell me what to start to send to it.
I started with these lines yesterday.
As you can see, PICkit 2 is recognized.
[ElectriciansForums.net] How to shield a live wire at 240V ?
But I am not sending something important to him in the code. And I have no clue what is the correct way to send instructions anymore. Maybe you can help me. I know I made it work in 2001 with a special "recipe" in the beginning. But I dont know what it was anymore. Or it was only for certain PIC's like 16F84?
Or at least where to look and search how to transmit the correct header or start of the code?
Thank you !
If I try to program it, I get this error: (the red line)
[ElectriciansForums.net] How to shield a live wire at 240V ?
 
Last edited:
And here is how it looks in reality.
The position of the PIC chip is correct, it's chip key pointing up towards the pickit2 black thing programmer.
The leds are connected through those 4 white jumper wires, because this is a 8pin chip and you have to rewire those pins.
I connected:
07-10 = RA0-RC0 = led1=DS1
08-11 = RA1-RC1 = led2=DS2
09-12 = RA2-RC2 = led3=DS3
03-06 = RA3-RC3 = led4=DS4
[ElectriciansForums.net] How to shield a live wire at 240V ?
 
Good morning. I would have to do some reading up first - quite a bit - before I could begin to help. I will see what I can do but it would be at the expense of my Version 3 so I would prefer not to. You might want to ask elsewhere for an earlier response. I have not used a Pickit before. One day I want to buy a Raspberry Pi but at the moment I rather like doing digital circuits 'long hand' using discrete logic ics.
 
Good morning and thank you for your response.
If you didn't work with this kind of hardware then I will not put you to trouble.
I will ask somewhere else then.
Here is the datasheet for this particular pic 12f508.
Maybe you have luck and you can find the initializing code for it. Take a quick look, maybe you are lucky. If not, then is good that I try it through you as well.
That code that i write there is from other codes, I didnt look (too hard) in this datasheet yet. I did peek in it but not for too long. But I will in the end if nothing else come out.
 
Is there a forum group for the PICS where you could ask a question? Or even the Manufacturer's help line? I am of no help I'm afraid to say.

I'd agree with Marconi, check out a more relevant forum. It's over twenty years I think since I programmed PICs, so I won't be much help either.

I used a home made programmer, a very simple one if I remember rightly, to program 16F84s I think. Or was it 16C84s maybe. Anyway, I'm waffling now, but hope you get it sorted.
 
I used a home made programmer to program 16F84 as well.
But I have all these 12F508 and I want to use them in some very smart little projects i have in mind.
I managed to built successfully a 16f690 with an older program i had saved there. But nothing on the demoboard, the 4 red leds are not doing anything, yet. I have to figure out the protocol which i totally forgot.
Im not sure exactly what i did back then. I think those saved (working) files were working for this pickit2? or for a serial port? I am not sure.
 

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