Fabricating your own PCB at home

[turbokon]

So now that I finally successfully completed thesteve's component mod on my TG16, I was thinking how can I make a professionally looking PCB.  I did some digging and found this on youtube and this http://www.riccibitti.com/pcb/pcb.htm.

Looks doable.  I would like to know if anyone here have ever created their own professionally looking PCB.

[TheOldMan]

Yes. The protocade cards were made in a similar manner.
It's not as easy as it sounds, though
And a cheaper alternative to Etching solution (Freeic chloride?) is Hydrochloric acid, aka toilet bowl cleaner. Seriously.

[Tatsujin]

I did, but mostly for working purpose using everything pro stuff (protel) and pcb manufacturers. but during my apprenticeship, we also had our own little PCB manufacturing equipment -> plotter, exposure unit, etching bath, but for double-layer only.

we also still did handmade layouts with black tapes on clear films.

was a funny time, because I could use it for personel use as well. damn, already 20 years since.

[SignOfZeta]

Wow. That's pretty cool. I did this in school back in the 80s with black tape but this looks faster and more precise...for this guy anyway.

Also, I love his karaoke effect voice.

[BlueBMW]

I did the region mod chips using pad2pad.com   Not too terribly expensive...

[turbokon]

I never did anything like this when I was going to school. Looks fun and I'm up to the challenge:). Going to try to see if I can build one myself. I want to build a component mod pcb as small as possible using SMT components so that I can use it on a turbo express also. I will capture the build process here as I TRY to build it.

Thanks blue, I will check out pad2pad.com also.

Just want to give a shout out to thesteve for coming up with the design.

[turbokon]

Blue, good advice on using pad2pad.com.  I used pad2pad.com to create the board layout.  The board will be 2.5" by 2" and I will be using 1206 resistors/caps and SOT-23 npn transistors.  My next step is getting access to a laser printer.  Here is what the board layout looks like.  If anyone is bored, please review it against thesteve design, http://www.pcenginefx.com/forums/index.php?topic=13231.0. I would greatly appreciate any suggestion or input.

[Duo_R]

How much would these be? Also is anyone amping the RGB lines because the colors look really dark.

[turbokon]

Duo-r, I was planning on creating the pcb myself so I don't know the cost to have it mass produced by pad2pad.com.   The RGB amp is a different design. I used 500ohm for r2 and pots for r6 & r4 and I got good colors with the r6 pots at 3.2kohms and r4 at 3.4kohm. I'm not sure if changing these value having any bad side effects on the circuit but I'm getting good results. I can post up an updated video this evening.

[TheOldMan]

I take it you are lookng to have pad2pad make the boards then?

Doing double-sided boards at home is a -much- bigger hassle than you think. Besides getting the layers to line
up correctly, it is very difficult to make a good via - you end up soldering wires on both sides of the board to connect
the two layers.
I would also suggest using thicker traces. Small ones are very difficult to etch without breaks. You have plenty of
room there, so use it. (It will also reduce the etch time).

Finally, talk to thesteve and find out the best place to put trimmer pots. You had to adjust resistors to get the colors you wanted; there is no guarantee that other pces will have the same signal strength as yours. So, if possible, make it adjustable, so people can tweak the output to get the colors they would like.

[BlueBMW]

You can estimate the cost from pad2pad right in the program.... if I remember right it was about $240 for 500 of the region mod chip boards.

Get in touch with the steve and show him your layout, he will advise you on how to tweak things!

[turbokon]

theoldman, I tried arranging some components to see if I can get all the traces on one layer but I couldn't.  Also I was able to increase the traces up to .060" before the program start giving me traces failures.  So I will go with the .060" width.

Blue, I thought I read somewhere that you and thesteve were planning on mass producing a PCB that would output RGB, component, s-video and composite all on one chip.  My goal is to produce a few pcb for my systems only but if you guys are cool with it, I can try to get the component mod only pcb mass produced.  I have sent a PM to thesteve for his input.

[BlueBMW]

Weve been tossing the idea around and I started some board layout work but time seems to be my enemy.  Please feel free to take up the reigns on the project!

[TheOldMan]

I tried arranging some components to see if I can get all the traces on one layer but I couldn't.  Also I was able to increase the traces up to .060" before the program start giving me traces failures.  So I will go with the .060" width

Hmmm. 0.060" traces works out to 0.154mm. That could be tough to etch at home, but should be doable with practice. Somewhere in the pad2pad stuff is a setting for how much space to leave between traces. Maybe tweak that if you need to.
Also, the auto-router works, but definately could be improved. You are going to have some vias, that's pretty unavoidable, but try to minimize them as much as possible. Assuming you are mass-producing them at home.

If you are serious about etching them at home (and for a prototype to make sure things work, it's fine), put some un-used vias in the corners. Then after you print the pattern, you can stick pins through them to align everything before you tape them together for transfer. When you go to connect the top and bottom at the vias, the best thing I found was to use a wire that almost fills the hole. Smaller wires move around to much. And don't feel too bad when you start swearing at it

And fwiw: once you have 2 or 3 that work, and you know how to build/install them - ask around here for pre-orders. You might get enough pre-sales to cover the cost of getting the boards made. People around here do that

[turbokon]

Thanks for your input oldman:) Actually, I wasn't planning mass producing this PCB but after talking with Blue I may.  But for I do, I just want built one at home as you said a "Prototype" to make sure everything is working. 

Here is a video of me playing R-type in "HD"