[aprssig] Prototype hacker question...

scott at opentrac.org scott at opentrac.org
Thu Jul 29 10:33:46 EDT 2004


>Only the part isn't SOIC.  It's something called a 'wide' SOIC.

Isn't that fun?  I just did one that I THOUGHT was a 14-pin wide SOIC, and
it turns out it's a 14-pin SOP.  Fortunately I just wasted one home-brew
board on that.

USUALLY what I do is print out a 1:1 copy of the layout on paper, then place
all of the major parts on it to verify that they fit.  For through-hole,
sometimes I'll put the paper on top of some anti-static foam and push the
parts through.

>So, anyone have any other ideas?  Or hints and tips on how to bend
>leads consistantly to do this?  I don't want to have to spend a day
>fudging each board together...

Well, you might check and see if there is a narrow SOIC version available.
For the MAX232 chip, for example, they usually come in a wide package but I
discovered it's possible to find them in a narrow version.  Or maybe an
equivalent part from another manufacturer would work.

Other than that, I'd suggest placing the edge of the part on a hard surface
like a workbench and 'rolling' the leads underneath it, like you do with new
DIP parts to straighten the pins.

It's a major pain for complicated SMT boards, but I usually try to do at
least one hand-made board before sending it to the board house.  Helps with
peace of mind, and I've caught some subtle glitches that way.

Scott
N1VG





More information about the aprssig mailing list