10 Nov
1998
10 Nov
'98
7:18 a.m.
On Tue, 10 Nov 1998 Philip.Belben(a)pgen.com wrote:
Person who said check continuity between centre pin of
socket and ground on
the machine. That tells you if it _is_ connected to the ground plane. Sam
wanted to know if it _should be_ connected - i.e. he seems to be adapting a
machine for which he has no PSU to work with a PSU he has.
Exactly.
If the supply you are using is a regulated 5V supply,
then + and -
terminals go to +5V rail and ground plane respectively.
If it is not, try and trace supply rails back to a regulator. It should
then be possible to work out which way the regulation is done.
There were several polarity sensitive caps on the supply regulator board,
so tracing back from the negative side of one of the caps I found out that
the unit wanted a center positive supply.
So I'm glad I took the time to check, otherwise I may have blown a
perfectly good scanner and would have had to ask many more questions.
Thanks for all the help!
Sellam Alternate e-mail: dastar(a)siconic.com
------------------------------------------------------------------------------
Always being hassled by the man.
Coming in 1999: Vintage Computer Festival 3.0
See http://www.vintage.org/vcf for details!
[Last web site update: 11/02/98]