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[on:]

Hi, i spend some minutes trying to do my first pcb, basically it's an arduino with a 3.3v regulator so i can connect a nrf24l01 chip.
If it's alright i will buy some ferric chlorid so i can make my first pcb.

Please give any hints, opinion, advice...

[Reply #1 on:]

Lots of demos on YouTube.
On your PCB make your Vias the same size as the other pads (if the software allows you to).
I make the IC & Vias pads 80mils, Regulators 120mils, Switches 100mils.
I always elect to make single sided boards with jumpers rather than double sided.
I sometimes add a few transistor/resistor/capacitor pad footprints just in case I want to add a modification later.

[Reply #2 on:]

I guess some people are having success, but my plan is...  I'm NEVER going to attempt it again!

I made some boards many years ago.  It was messy, the boards looked homemade, the drilling was not very accurate, and I don't remember what other problems I had, but it wasnt' much "fun".  It probably took a couple of attemps to get a working board.   

When I went to college, there was a lab where I could get boards made from my supplied artwork.   Since graduating from college, I've built several projects permanently on plug-in "breadboards", and sometimes I use perfboard and hand wire.   In the past I also used some wire-wrap.

If I ever decide to make a custom board again, I'll use a service like ExpressPCB to get the boards professionally made.   

[Reply #3 on:]

Hi, i spend some minutes trying to do my first pcb, basically it's an arduino with a 3.3v regulator so i can connect a nrf24l01 chip.
If it's alright i will buy some ferric chlorid so i can make my first pcb.

Please give any hints, opinion, advice...

Pin 8, GND, appears not to be connected (or is there a ground plane?)  The ground trace for the crystal load capacitors
seems to be unconnected too.

No 0.1uF ceramic decoupling capacitor(s) on the Vcc and AVcc pins?

[Reply #4 on:]

DVDdoug, your experiences are very personal.  It is my opinion that not everyone needs to take your advice and give up making their own PCB before they even try.

With a little patience and experience you can make perfectly good boards at home.

Example:

1) Making a PCB at home is not fun, for you.  Others may like it as I do.
2) PCBexpress is a sort of good with the bad experience due to proprietary tools.  There are probably much better examples of of good places to get PCB's made...   like maybe ITEAD.

http://imall.iteadstudio.com/open-pcb/pcb-prototyping.html

3) I don't run around telling people "Don't eat cabbage because it sucks and smells funny."  I allow people to figure things like that out on their own.
4) They said they were going to buy some ferric chloride... so farming it out does not seem to be in the plans.

Here is how I make mine:
http://pwillard.com/files/DIY%20Single%20Sided%20PCB.pdf


As others have said... you can't really do double sided PCB's at home without at least getting better experience at single sided... so you want to design your board so that IF you need TOP SIDE traces,  they are all the shortest possible straight lines you can run as "jumper wires".

Designing PCB's is sort of like solving a complex puzzle.  It can be a rewarding experience if you let it become one.  Using surface mount parts is usually done to save space... but since you are using many through hole parts already... It might be easier to just use ALL through hole parts... that way, everything is on the same side... but that is a personal choice... up to you.

One design idea... Avoid using all sorts of angles... pick only a few, like maybe 45 and 90 for all traces.



CARL: I'm assuming you are trying to use a laser printer toner transfer method...  I've done it for a long time you... if you have questions... feel free to ask.

[Reply #5 on:]

@ OP A good "First Attempt" And I did that work from design to turnkey work for nearly 35 years.
@pwillard.. GREAT looking work, home made but not obviously so. There were no location marks on the individual boards for cutting and that was the only real giveaway.
Spot on constructive criticism too.
Bob

[Reply #6 on:]

@ OP A good "First Attempt"

And done with Fritzing. That should annoy somebody...

[Reply #7 on:]

Hear, hear, pwillard!

I've had a lot of fun over the years, making my own PCBs.

Now... they may not be brilliant, they may not often use SMT, they may not be "professional"... but they clear up my proto-boards for the NEXT project, and are reliable and robust. (How many times has my CCTV enabling circuit gone down because that wire has come out of the proto-board, AGAIN!?... note to self: Get the PCB for that finished, installed.)

Guidance for, to me, reasonable compromise between hopelessly amateur and hopelessly expensive tools and techniques...

http://www.arunet.co.uk/tkboyd/ele1bp.htm

[Reply #8 on:]

hi pwillard

nice boards, have you tinned the copper with something if so what do you use?

just wondering what are the squares in the left board are for? some sort of noise reduction maby ?

also whats the bottom right board for?

cheers

[Reply #9 on:]

nice boards, have you tinned the copper with something if so what do you use?

I use COOL-AMP powder.  http://www.cool-amp.com/cool_amp.html

Even just a 2 ounce bottle would last you a very long time.

I also sometimes use MG chemical's "Liquid Tin" that comes in a pre-mixed and ready to use bottle, but I like the results a bit less than what I get with Cool-Amp powder.   Using Cool-Amp does require a bit more work though.

just wondering what are the squares in the left board are for? some sort of noise reduction maby ?

No, that is my way cope with 2 things... 1) if you have a ground plane, you save on etching time... less to etch away.  2) If I have a large ground plane, my Lexmark printer starts to make a very thin toner layer... which will show as bleed through etching.  The small squares and gaps break up the ground plane but also keep a lot of copper un-etched.

also whats the bottom right board for?

That is a for my outdoor heated RAIN SENSOR.  It's basically a 2-wire mesh that can detect the conductivity of rain drops.


Note: The board on the LEFT is actually my ATMEGA 8,168,328 programming fixture.

[Reply #10 on:]

Posting a schematic helps for the group review.
For instance, it would make it more obvious that there are no decoupling capacitors on Vcc, Avcc, or Aref.
Gnd pin 8 on the chip does not appear to be connected.
The crystal caps are connected to ground thru the reset switch. etc.

[Reply #11 on:]

If I ever decide to make a custom board again, I'll use a service like ExpressPCB to get the boards professionally made.   

The latest DipTrace has an order online option right on the menu that sends the board data to Bay Area Circuits, checks against their design rules, lets you pay from PayPal, etc.  Total convenience, not as cheap as Chinese manufacturers, but you will get it faster and the board I did worked first time and looked great.  3 small boards is usually about $30 or so plus reasonable fast shipping so prototyping out of DipTrace (free 500 pin version available for asking and 300 pin for not asking) is really very straightforward and convenient.

[Reply #12 on:]

Is diptrace the program that is being discussed elsewhere in the forum, it bypasses some of the windows security settings as part of the installation?

[Reply #13 on:]

I used expressPCB for my first board, a simple 20 LED board arranged in 3 sections with 3 transistor drivers, a 4th transistor as a line receiver/signal inverter, and 7805 for 12V to 5V power supply. The signal was the TX from another board going to a promini, as was the 5V. The promini drive the 3 transistors. (A single 7406 would have worked as well, but I had this drawer of 1980's era transistors I wanted to finally use).
When my designs got more complex, I moved to eagle.  The expressPCB rubberbanding leaves something to be desired. Eagle was awkward at first, so many parts options, took some getting used to.

[Reply #14 on:]

Is diptrace the program that is being discussed elsewhere in the forum, it bypasses some of the windows security settings as part of the installation?

Yes, I think I brought it up on another thread and that comment was made.  But I am not going to stop commenting on it because someone says it bypasses a security feature of Windows during install.  If true, it means their installer sucks, it doesn't mean the software is spyware or anything like that.  Parallax uses DipTrace now for their PCB design work.  Given how popular Eagle is, I would have never tried anything else if it wasn't for their 100x160mm limitation and huge price jump to get beyond it.  DipTrace works well, has no set PCB size limitation (the free version is limited to 300 pins, 500 pins if you ask to be upgraded to this second also-free edition for the price of your email address).  I installed DipTrace on Windows 7 and I didn't have to elevate rights so I am not sure exactly what the installer is doing that is non-kosher but it sure doesn't require more than normal user rights.

http://www.parallax.com/productinfo/diptrace/tabid/922/default.aspx
http://www.diptrace.com/partnership.php