group buy for homebrew CPUs?

der Mouse mouse at Rodents.Montreal.QC.CA
Sat Aug 12 15:48:43 CDT 2006

>> This sounds as though you're talking strictly about soldering them
>> to a printed-circuit board.  If so, that's a lose right there,
>> compared to DIPs, if you can't connect to them (without equipment
>> prohibitively expensive for hobbyist use) except via a PCB.
> Well that's pretty much a given...there's really no other way to do
> that.  [...]

So, there's a fairly clear way in which surface-mount is harder to work
with than DIPs: you can't breadboard the things, and doing flying leads
is (at best) a good deal harder.

> Quick-turn PCB houses are super cheap these days, though,

Hm?  So moving to SMT means that instead of buying a $1.19 part to
breadboard a circuit with, I instead can buy a $0.89 part and throw
$12.99 at the minimum order for a PCB so I can connect to it.

Remind me again how surface mount is better?

Oh, okay, let's say I can bundle ten chips' PCBs into that order.  So I
have $0.89+$1.299.  This is still a dollar more than the $1.19 DIP.

> As I've said a few times, things are *different*...trying to treat it
> like "a smaller version of through-hole construction" will not work.

Different...and harder, it appears, since at a minimum you need less
common (and more expensive) tools, and that's if you're doing a
finished design and just trying to assemble the thing.  If you're
breadboarding, even your parts are more expensive, since you have to
add the piggyback carrier to the part cost.

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