So I'd like to build my own PCB - how do I do this?

smalltownguy2

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So I'd like to build my own PCB - how do I do this?

I've got a complete schematic, parts list and lots of motivation.

Anyone wanna share with me the best way to go about building my own PCB?

It's a sound board for an obscure pinball machine I picked up. I've scavenged RGP, every forum I can find, and asked around. I just can't seem to find a replacement board for this pin.

So, I figure, why not? I'll build my own PCB. After all, most of the parts are off the shelf components. The ROMS I can burn - I have the images.

Anyone have any suggestions?
 
http://www.amazon.com/Complete-Desi...9714/ref=sr_1_1?ie=UTF8&qid=1309491288&sr=8-1

It does a fairly decent job of explaining the process from concept to manufacture. It does glaze over some of the smaller nuances of OrCAD, but only because there's so many. It gives you all of the defaults you would use for a standard run. There's also lots of math if you're a masochist. But unless you're doing high-speed designs, you can skip that chapter. I've done three designs with this book and OrCAD so far.
 
You could also look into farming it and have someone else do it. Either way, each has their own advantages and disadvantages.
 
How big/complicated is the board? You can always just point to point it, or wirewrap. If it's a fairly simple sound board, with 6 or 8 large chips/ROMs and some glue logic, wiring it by hand won't be too terrible. Wire wrapping is fun and easy. But if it gets above a certain level of complexity, you really need to have boards printed, or do your own etching (which can be it's own pain in the neck).

-Ian
 
It's not TERRIBLY huge, but it's big enough. I'd rather commission someone else to build it, but I will start looking into the programs to design one too.

The board schematics can be found online here:

http://www.ipdb.org/files/403/Grand_Products_301_Bulls_Eye_schematics.pdf

I have the original documents, with the parts breakdown and schematics, so I have everything I need to get this going.
 
You are going to need the code for the eprom on that sound board. Without it, the board is useless.

Bill
 
It's not TERRIBLY huge, but it's big enough. I'd rather commission someone else to build it, but I will start looking into the programs to design one too.

The board schematics can be found online here:

http://www.ipdb.org/files/403/Grand_Products_301_Bulls_Eye_schematics.pdf

You can point to point or wire wrap that without any problems. It would be a lot less work than trying to draw up a PCB and get it printed/etc. All the digital logic stuff should fit on one large Radio Shack perf board. I'd probably build the power supply section on a separate board though.

-Ian
 
I used to do wire-wrapping. I've found that the amount of time you put into wrapping, checking, double-checking the connections, then when you're done realizing that you wired something wrong, but because it's buried underneath so you have to move the wires around and cut carefully, then realizing that you cut the wrong ones so you have to re-cut and re-wrap, and well, ... you get the idea.

Also, wire wrappings will degrade after a few years. After about 6-8 years you'll start to see signal integrity issues, if it applies to your application. With PWB fabrication there is a steep learning curve, but once you get over it you can whip out board designs in a fraction of the time, have them be more-reliable, and reproduce-able in case you feel like making millions off them. :)
 
If you're gonna do it, I'd definitely do a PCB... wire wrapping that wouldn't be fun. But, making a PCB for that won't be just a couple hours of work either, especially if you've gotta get over the learning curve of the PCB design and the PCB software.

Honestly, you're gonna spend a LOT of time on it, and it'll still probably cost a hundred dollars or so for the MFG of the board and parts (assuming you only have a few boards made). Is the game worth it, and is an original board REALLY unobtainable?

Of course, PCB design is a useful skill, so if you're using this as an excuse to get into it... that looks like a great project for that.

Edit: I also wouldn't reproduce the entire circuit... there's the main part, which does the important stuff... then there's just an everyday 5V regulation circuit and audio amplification circuit, which I'd leave off. Those can be had from anywhere.

DogP
 
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Do you know the original PCB size for this board? That will be the determining factor on the cost.

The circuit doesn't look all that complex, the only tricky part for a novice may be understanding the CAD tool enough to use BUS connections for address and data.

Also I didn't see it listed but what type of connectors are used? I assume molex, but are these .156 spacing molex or something else?
 
Honestly, you're gonna spend a LOT of time on it, and it'll still probably cost a hundred dollars or so for the MFG of the board and parts (assuming you only have a few boards made). Is the game worth it, and is an original board REALLY unobtainable?
Which is why I suggested he just point to point it. Sure, it'll take a couple afternoons, but it'll be faster and cheaper, especially considering this is a one-off. The parts cost won't be too bad, because there really aren't that many parts.

Point to point or wire wrap construction can be quite reliable if done neatly. Wire wrap even more so - done correctly, the joints are gas tight.

Edit: I also wouldn't reproduce the entire circuit... there's the main part, which does the important stuff... then there's just an everyday 5V regulation circuit and audio amplification circuit, which I'd leave off. Those can be had from anywhere.

I would probably reproduce the original power section and amplifier - after all, it's a really simple circuit. Actually, I'd probably just do the power section, since it it's really basic and easy, and it would be probably be easier to just build that then to find an existing board that does that - then just use the amplifier from a set of cheap computer speakers. I'd build the power section as it's own little board - keeps the heat away from the "important" section.

-Ian
 
What about something along the lines of ExpressPCB.

I used it to make my Berzerk battery replacement boards, wasn't difficult at all. And when you're finished with the design you can order the boards directly through the software.
 
I still have some wire wrap projects that are still in the field and still working 20 plus years later. So, I really don't think reliablity is an issue.

I know you want this pcb board. The question is do you want to learn this skill?
Sometime it worth just paying someone to build you the art work and the board.
Instead of learning the whole process and producing this board.
 
I know you want this pcb board. The question is do you want to learn this skill?
Sometime it worth just paying someone to build you the art work and the board.
Instead of learning the whole process and producing this board.

Considering that a little over a year ago I didn't even know what a flyback was, I'm pretty sure I can learn this.
 
You should probably download a few of the free versions of the CAD software and pick one that you like.

I haven't tried Eagle but it seemed like the most versatile of the freebies. I think it has both the Schematic side and the Layout side.

One of the free CAD progams is just the Layout portion, you just lay down the footprints and traces. Might be a little easier to learn but less options if you decide to move to bigger projects later on.
 
Yeah, I'd probably go with Eagle... it's pretty popular, definitely capable, and it's not too difficult to use. I've used Eagle a little bit, and also Diptrace (good, aimed toward the hobbiest), Mentorgraphics PADS (professional, expensive), and Altium (again... professional and expensive). I currently use Altium for pretty much everything, but we paid ~$6k for the license (for work), so I figure I might as well use it. ;)

Definitely get one that does Schematics and PCB design... it's very nice to basically just copy the schematics from paper into the program, and then in the PCB portion, everything is connected with the ratsnest (straight lines showing connections). That helps initially with how to place parts on the board, and then gives you an idea how to route everything.

DogP
 
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