Stefan Trethan wrote:
>On Mon, 31 Oct 2005 21:12:16 +0100, Alan King <alan@...> wrote:
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>> Eagle also has some DB style connector layouts that are for board
>>edges, with board fitting between the two pin rows on the back of the
>>connector, 1/2 pins on top and 1/2 pins on bottom. Is a very good,
>>secure method still with no holes, and you can do similar with 2 row pin
>>headers etc sticking out from edge. Between that, top mounting dip
>>style chips, and wrapping traces over the edges, I hardly ever drill a
>>hole in anything now, no pins as well as vias. Just so much easier to
>>not have to get out the drill and have dust, even with CNC.. Even when
>>I have boards made now, I'm starting to top mount the DIPs and do edge
>>type connectors, it just makes things a bit easier.
>>Alan
>>
>>
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>While i also use the edge-on D solder cup connectors they still give you
>some of the signals up top and some one the bottom layer, kind of a little
>drawback. Bending traces over the edge is a interesting idea, might just
>try that.
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Yep they are not perfect, but fortunately for LPT and serial port most
of the important signals are on top, usually only 2 or 3 wires the
bottom. At first I did the bending literally, with wires soldered on
one side and bent to the other. Much faster to just use header pins or
something else straight, run solder down the pins/traces, and make
fillets, so definitely start from there. There used to be lots of
commercial equipment made this way, BMW stereos had boards soldered on
edge to other boards like this, with many traces making the 90 degree
solder connection. Often needs a resolder after even a small impact
like a deer or something, because of the inertial effects breaking some
joints.
>Drilling is nasty, yes, but not _that_ bad. As long as i don't have to
>drill hundreds of holes that's ok with me.
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Oh yes, as always minimize work, but still stay flexible when doing it
to take best advantage. Even though it's very good to avoid as much as
possible, a via hole here and there is still sometimes better than
trying to get every last signal to an edge of the board. But once
starting with the idea in mind, I can usually get it to only needing a
jumper here and there, and just wire a few top to bottom instead of
getting the drill out.
Alan