5 Jul
2000
5 Jul
'00
1:23 p.m.
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
Often it's not the breadboard but the crude oscillator circuit that was
used. the basic osc used in theory should never work but crystals are
less deterministic and don't know that. The side effect is hard starting
and a slight offset from the marked frequency.
> That's so true! I was surprised to read in
the spec's for my first
ones
> (and last, by the way) that the capacitance
between adjacent contacts
is 5
pf, I
don't remember much else about them.
And that's probably being somewhat optimistic!...
I have certainly seen microcontrollers fail to clock properly when
they've been used on these breadboards. Hang a xtal and the 2 33pF (or
whatever) capacitors off them and the strays will mess things up. Since soldering is so much more reliable, and just as
fast once you get
used to using the soldering iron, I don't see the point of said
breadboards. But anyway...
Different issue.
FYI I breadboard on a peice of cheapo copper clad AKA dead bug or
as the RAH calls it "ugly" construction. Works well and the groundplane
is hard to beat. Either name, you lay the bugs upside down and point
to point wire them (solder, programming language #1). Copper is ground
and everything else aint. Goes together fast and tends to be fast logic
and UHF friendly.
Allison