Eagle Tips, Tricks, Help and other Useful Information

[RnFR]

i found it. it was ending up in the latest folder i created.

[Maxwell]

Cool thread - I've really been getting into EAGLE lately.

As far as making the actual PC board, generally what is a good width for the PCB trace in a guitar pedal? I think I've been using .032 in mine.

[madbean]

Yeah, 32 is a good size. That's what I use. Occasionally down to 24. Actually, if I set up my grid to smaller divisions I could probably go down to 16 and make some boards smaller, but usually most circuits don't pose a problem. If you were designing something to go in an 'A' size enclosure, you could maybe do a grid set at 10 mils with a multiplier of 5 and then use a 12 or 16 size trace. I don't know how consistently that would etch using DIY methods.

[Evz]

Hello there, just got eagle few days ago and started playing around, i want to try and print some board off for my self and if they go well maybe order small multiples of single boards,

so i was wondering, i got the markov libraries, and am using a pcb mounted 3pdt switch, but it shows me the drill holes are circular, and small, is there anyway to elongate them so IF i decide to get these manufactured they'd drill them the right shape/size?

ps any suggestions where to order small order cheap pcb's from? (i noticed futurlec is VERY cheap)

[marshmellow]

No, that's what the part is designed like in the library and you would have to modify that. If you want bigger pads, you could use the library wirepad and place 9 pads by hand.

[Evz]

Would it work if i change the drill on the switch pad to a diameter equal to the lug size (0.078) and then make the actual pad size square around 0.1 inches? would that work if i get boards made or etch them by hand?

[madbean]

Try this; open up the GM 'switches' library by double clicking. Then open 'packages' and click on the 3pdt package. Set your grid to millimeters. Now, Change->Shape->Square and click on each individual pads. Next up: Change->Diameter->3.81 and click each pad to change their diameters. Finally, repeat the previous step with Drill; Change->Drill->2.8 for a larger drill size.

I don't know if these diameters and drills are a perfect match...you might want to print an example out and compare it to an actual 3pdt. But, this will at least get you very close.

[irmcdermott]

Ok. The past few days I have been trying to create a custom part in Eagle, but I am having no luck. I am trying to create a CD4007UBE. There are one or two in the libraries, but I really don't like the schematic symbol in either, and there isn't one in the GM libraries. Does anyone have it? The symbol i've been trying to make and that I have seen in schematics looks like 3 N-channel and 3 P-channel transistors all connected together like the pinout diagram in the datasheet shows. I'm just having no luck and if anyone has something similar it would be awesome. I'll keep trying, but I've followed all of the tutorials I can find and can't get it right. Thanks.

Ian

[marshmellow]

It's exactly described step by step in the manual. I wouldn't know what more to say about it

[irmcdermott]

Finally figured it out. One other question. Eagle freezes up on me every time i try to export an image? Any one else have this problem or have a solution? I'm on a Mac. Thanks. If I can fix this I can start to contribute rather than just asking questions. Thanks!

Ian

[irmcdermott]

Alright, figured that out too. Sorry about that.

[chicago_mike]

Hey guys. I'm redrawing a fx loop pedal in Eaglecad and theres a few vref connections.

These just go to the 9volt connection? Or are these like test points?

[JiM]

What kind of pedal is it ?
Vref is often used for Vcc/2, when using opamps with a single 9V power supply.
It can also be a reference voltage for an ADC or a DAC, or any bias voltage ...

You can tie them all together first (i.e. with a supply symbol like Vb or Vdd ...), and then figure out what it's used for.

EDIT : by "FX loop pedal", do you mean a passive loop switcher ? Then maybe it's just the power supply for the LEDs, and could have been named Vcc.

[chicago_mike]

Sorry , ill be more clear.

Its an fx loop pedal. With 2 opamps, tl072's.

http://klaas.homeip.net/wb/media/pdf/WK_Blender_EQ_V2.pdf

Thats the schematic and I am redoing it in eagle. But instead of the switches and jacks I am using pads, and and connectors.

And what I'd like to do is not have to run a bunch of lines in eagle for the +9. I'd like to use some kind of symbol for the 9 volts.

I see +9 symbol, vcc, vref, just figuring out how to finally use them.

[marshmellow]

Use the symbols in the supply libraries. Use 'show' and clicking on the different nets to make sure everything is connected the way you want it.

[chicago_mike]

Hey all,

How do I make sure I export a 1 to 1 ratio of my pcb? I dont really want to put it into a graphic editor, only to invert the monochrome output. I can never resize perfectly.

[madbean]

If you are exporting a png file, then the output ratio should be correct. All you need to do is match the DPI of the document you create in the image editor to the DPI you selected when exporting from Eagle. Some image editors will automatically choose the right DPI when you open the png file (like Photoshop).

[JiM]

When exporting to an image, you can choose the resolution, for example 300 dpi (dots per inch). Just make sure to use the same setting on your printer.
It might be useful to add a small calibration scale at the edge of your layout, e.g. small dashes of "dimension" or "silkscreen" spread 0.1" apart. You can then check with a ruler that the scale is OK.

You can also avoid inverting the image outside of Eagle, by choosing an appropriate color theme in the preferences. A white background is not comfortable for editing a PCB layout, but useful for export.

[chicago_mike]

I promise!

What common trace thickness / width do you guys use for the layout? Right now I have traces going inbetween pins on an ic, and that seems too think to do press-n-peel or the laserjet-photopaper method. is .024 more normal?

oh...and do you guys name your nets and whats the advantage?

[madbean]

24 is good if you are using ground pour. If not, then bump up to 32. I never name nets, although Eagle will do some automatically like 9v, ground, and Vb (if you are using the supply pins from the library).