Path: utzoo!attcan!uunet!comp.vuw.ac.nz!am.dsir.govt.nz!dsiramd!actrix!geoff
From: geoff@actrix.co.nz (Geoff McCaughan)
Newsgroups: sci.electronics
Subject: Re: question about computer power supply
Keywords: computer power supply
Message-ID: <1990Jul17.041755.28225@actrix.co.nz>
Date: 17 Jul 90 04:17:55 GMT
References: <4924@uafhp.uark.edu>
Organization: Actrix Public Access UNIX, Wellington, New Zealand
Lines: 20
Summary:Sounds like a normal SMPSU to me

In article <4924@uafhp.uark.edu> hbj@uafhcx.uucp (Bernard Johnson) writes:
>
>I recently bought a NCR PC-6 power supply to power some hobby projects.  When I
>received the supply, I measured the outputs. The +12V line measured +4.95V
>and the +5V line measured +4.8V.  I have been told that the +12V line will not
>be +12V until a load is connected to the supply.  I was told that the scheme
 
Sounds like you have a normal SwitchMode PSU. Normally these need a
minimum load in order for the regulation circuitry to operate, many have
overload and underload protection. 

I once had an SMPSU (from an I*M peecee as it happens) I was using to
power a Hard Disk. It would spin the drive up, but once the initial load
dropped off it would underload and switch itself off. Adding another
drive fixed that problem.  
-- 
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Geoff McCaughan        Email: geoff@actrix.co.nz  Phone: +64 3 539545 or 852101
Amiga/Hardware/Unix/Quantum Mechanics Hacker      Phax : +64 3 539567
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