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Macintosh SE no video.

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fastxfurious

Member
Joined
Jun 20, 2015
Messages
10
I recently purchased a macintosh SE. When I try to start the computer I get the macintosh chime and a flashing yellow light above the disk drive. When i opened the case there is part hanging off the crt. I have concerns about pushing this piece back in place because of the high voltage. Screenshot_2015-07-11-23-45-36.jpgScreenshot_2015-07-11-23-45-50.jpg
 
That's the CRT socket. Best case scenario is that it fell off due to heavy vibrations, in which case you just line the pins up with the socket and push it in. You don't need to worry about high voltages around here.
Worst case scenario is that the tip has broken off and the the tube has Gone To Air, in which case the CRT is dead.

a flashing yellow light above the disk drive
Click to expand...
Your hard drive is suffering from stiction. There's a few ways you can help it along.
 
Thanks for the help. One of the prongs on the tube is bent would it be ok to bend back into place.
 
No problem here, put it back together and have a try, the SE is reliable.

The chime is a good point and the flashing light also.
 
I pushed the CRT socket back into place no luck is there an easy way to tell if the CRT is dead.
 
fastxfurious said:
I pushed the CRT socket back into place no luck is there an easy way to tell if the CRT is dead.
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Close the curtains or go into a dark room and turn the machine on. do you see an orange glow form the neck of the CRT, indicating that the heater is working?
If you have no glow then either the heater has gone open and there is no easy fix for that, or the tube has Gone to Air and when it was powered up the heater burned itself open.....OR there's a problem with the analog board and no voltage is getting to the filament at all.

A less easy way to see if the tube has Gone to Air is to see if the getter has turned white. Under normal life it is a shiny silverish look. When exposed to air it turns white but generally it's hidden further up the neck under the deflection yoke.
 
Usually CRTs that have imploded from a broken neck have a big circle on the face of the screen where debris has smashed against the inside face of the glass. I've sometimes seen clear spots where the phosphor was blown off, but usually the circle is dark from the conductive black oxide paint being blown to the face of the CRT.
 
Ya that's what I thought I have several old TVs with dead crts. I will try to get more pictures today. Also I believe the heater is working.
 
if the CRT has gone to air, the second you fire up the machine youll get severe arcing through the electron gun, and almost immediate destruction of the horizontal output transistor.
 
fastxfurious said:
Ya that's what I thought I have several old TVs with dead crts. I will try to get more pictures today. Also I believe the heater is working.
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Good, so your tube at the very least is intact and holding a vacuum and your heater is good. Since you have already said you have not and will not touch the high voltage components I can assume that either the analog board is in need of a bit of work (totally not unusual as all the compact macs up to the SE/30 need this eventually) or your flyback transformer has died and you are not getting any high voltage at all. There is no really easy way to test for high voltage either without taking a few good risks.
 
NeXT said:
There is no really easy way to test for high voltage either without taking a few good risks.
Click to expand...

I guess if you had access to something like the EMF K-2 meter the paranormal guys use you could probably pick up the radiant em field the flybacks would throw out.. if the flyback was working i'd expect you'd get that static buildup you can feel on the front of the CRT as well, or maybe hear the high pitched whine if it was oscillating low enough.
 
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