WANT TO LEARN HOW ASSEMBLE CIRCUIT BOARD

jimjones3630

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Nov 22, 2006
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Northern Nv.
Hi,

The circuit best I can describe since haven't figured out how to post pics is
a mosfet with two resistors between the gate and battery (-)&(+).
Switch between batt. (+) and one of the risistors going to the gate.
Mosfet drain going to batt (+).
Mosfet source to light bulb.
Batt (-) to resistor going to gate and the light bulb.

The picture looks really simple even if the above doesn't sound simple.

So, I have seen circuit boards with bunch of little holes and no copper. Stick the leads from resistors and mosfet through holes and solder the other side to make connection between?

Seen solid sheets of copper. Don't have any idea how to use it.

Seen circuit boards already built with the little holes but also have leads of copper going from one to the other componet then solder dots at the componets. Looks like factory made.

I have heard reference to "etching out." How does that work?

Any help would be appreciated, especially if have visual aids to go with advice. If I see it can understand quicker.

Thanks, Jim
 

Secur1

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Sep 16, 2006
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HELLAS
The design you mention seems pretty simple, but to put it on a bare board....
Etching = putting the "lines" on the board for current flow and making an actual integrated circuit, i've worked with PCB's (Printed Circuit Boards) but i never had to make one from scratch myself, as the one's i wanted where product specific.
Have a look at these sites, maybe they will help you out.
http://wiredworld.tripod.com/tronics/pcb_techniques.html
http://styley.net/?p=52#more-52
http://www.netscape.com/viewstory/2006/05/09/pcb-etching-with-an-inkjet-printer/?url=http%3A%2F%2Fprojects.dimension-x.net%2Farchives%2F77&frame=true
 

bobski

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Mar 7, 2007
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The "solid sheets of copper" you've seen are probably un-etched PCB. It's not solid copper, but the usual circuit board material with a sheet of copper bonded to one or both sides.
The etching process goes something like this (It's been a while, so someone correct me):
Start by figuring out what pattern of traces and solder pads you need in order to connect the proper pins of the components you're using. Mask your circuit trace patterns onto the copper side of the un-etched PCB. Areas left exposed will be eaten away. Masking can be done with sheets of rub-on (I forget what the proper term for this stuff is) circuit traces, or even just with permanent marker IIRC. Once the board is masked, you drop it in a tray of etchant solution for a few minutes. The chemical etchant reacts with the copper cladding, removing anything not protected by your mask.
Once etched, you remove the board from the tray and rinse off any etchant, then clean off whatever you used to mask the board.
Drill small holes through your solder pads for the component leads, and you should be ready to solder. It's a good idea to protect the circuit traces with a spray coating of some sort, though not required. It can be done before soldering if you cover your pads with dots of masking tape or something, or afterwards by just spraying the whole solder side of the board.
Radioshack used to sell a PCB etching kit - that's what I used to make the only PCB I've ever etched.
 
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jimjones3630

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Nov 22, 2006
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Northern Nv.
To all thanks for the info. Now I have an idea of some different ways to do it and need to check out radio shack for some materials.


Thanks, Jim
 

mpf

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Oct 2, 2005
Messages
228
I am using a toner transfer method
http://www.pulsarprofx.com/PCB/a_Pages/1_Menu/overview.html
for my prototyping double sided PCBs 15mm x 25mm with 0.5mm tracks and small SMD devices

Not as easy as they say to get the toner to transfer evenly, but I manage.
Sometimes with manual touch ups.

Their suggested etching method works well. I would recommend it what ever method you use to get the pattern on the copper board.

matthew
 
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