[comp.sys.mac.hardware] Dead SE Power Supply

louis@aplpy.jhuapl.edu (Louis Vasquez) (12/14/90)

	I've got a power supply on my mac SE that seems to be dead.  When I 
hook it up to my oscilloscope I get a 6volt peak to peak AC signal.  But 
when I use my multimeter it measures 0 volts of any kind.  If anyone has some
insight into this, please let me know.  Also if you know where I can obtain
the schematics for it, that would be very helpful.
						Thanx,
						Lou (louis@aplpy.jhuapl.edu)

russotto@eng.umd.edu (Matthew T. Russotto) (12/14/90)

In article <1990Dec13.192409.8697@aplcen.apl.jhu.edu> louis@aplpy.jhuapl.edu (Louis Vasquez) writes:
>
>	I've got a power supply on my mac SE that seems to be dead.  When I 
>hook it up to my oscilloscope I get a 6volt peak to peak AC signal.  But 
>when I use my multimeter it measures 0 volts of any kind.  If anyone has some
>insight into this, please let me know.  Also if you know where I can obtain
>the schematics for it, that would be very helpful.
>						Thanx,
>						Lou (louis@aplpy.jhuapl.edu)


Are you trying to measure it with no load, by any chance?  That won't work
at all.
--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
     .sig under construction, like the rest of this campus.

louis@aplpy.jhuapl.edu (Louis Vasquez) (12/14/90)

In response to the person who said that I should try to connect my Power
Supply to a load before testing it... I had it plugged into the main board
and it didn't turn on the fan.  But I tested the fan with my own little 
power supply and it works.  Would this be considered a load enough?
					Lou,
					louis@aplpy.jhuapl.edu

aras@ecerl1.ece.ncsu.edu (Caglan Aras) (12/14/90)

Is this problem dependent on temperature? I had the same problem about 1
year ago; when it got cold, the power supply would not turn on. Try a
heat test on it. The Fan should be enough of a load.

By the way, if you find the schematics, I would appreciate it if you
could post where you obtained them, those things are darn hard to find!
If you cannot fix it, Maya computer was pretty good with mine, for about
90 dollars!

Caglan M. Aras    aras@eceris.ncsu.edu| Experts know more and
N. C State Univ.                      | more about less and
ECE Dept. Robotics Lab                | less till they know
Raleigh, NC 27695                     | everything about nothing!