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_at_30below.com | JC: "Yea, that's the place!"
| JC == Jeremy Christian
Received on Mon Feb 23 2004 - 13:41:13 GMT