Rumor has it that Vintage Computer Festival may have mentioned these words:
On Wed, 18 Feb 2004, Alfredo B. Roisenzvit wrote:
Hi. i don't know if you have it already. I
have one,. it is definetely
5V, however, I dont know if the (+) is inside or outside. If you know,
please let me know since i need to plug it in too...
Hi Alfredo.
That is the big question. The center pin seems to go right into a diode,
but I can't tell what side of the diode that is. The outside conductor
goes to the ground plane, which would indicate that it is negative? So my
guess is that this is center positive?
Anyone? Anyone?
AFAIK, *almost all* wallwarts were center positive. If the outer ring is
going to the ground plane, that *should* be the clincher, but... as they
say about assuming things...
The reason for this is supposed to be that if a barrel connector is
center-negative and is grounded, if the barrel touches any part of the
circuit that's grounded (which is usually a pretty fair amount) it will
short out the PS and possibly do bad things to the circuit. The risk is
_lessened_ when the barrel is negative.
This is why I'm *always* careful with wallwarts for my Tandy Model 'T'
computers - they are barrel-positive.
HTH,
Roger "Merch" Merchberger
P.S. I'm back... either someone hates me (plausible) or the listserver
software "forgot" me (equally plausible) because I just stopped getting
posts awhile back... Xmas was quite busy for me, so I've finally found the
time to get resubbed.
--
Roger "Merch" Merchberger | JC: "Like those people in
Celeronville!"
sysadmin, Iceberg Computers | Me: "Don't you mean Silicon Valley???"
zmerch(a)30below.com | JC: "Yea, that's the place!"
| JC == Jeremy Christian