Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

macintoshmartin

macrumors newbie
Original poster
May 29, 2010
26
0
Antarctica
Ok, today I tried to turn on my Classic but when I turn it on, i can hear the fan spinning and like it is running, but nothing shows on the display and I hear a crackling coming from the CRT. Does anyone know what is wrong?
 
I just carefully disassembled the Classic carefully, and when I took off the board on top of the CRT, it looks like a round glass piece came out, I think that is the problem

I think it's called the yoke assembly
 
Last edited:
Actually, it sounds like the nipple of the CRT (Cathode Ray Tube) has snapped off. If the piece of glass is cylindrical and about 4mm diameter, then that's probably what's happened. Time to buy another Classic (for a spare tube at least).

Take a look at this page:

http://www.kevinomura.com/macs/classicII/index.html

Yes, some images are missing :rolleyes:

The third image down shows the tiny glass nipple in the middle of the CRT "neck" pins. Behind the gold colored rings is the "yoke".

I've seen these get snapped of in transit, or if the crt neck board (the small rectangular circuit board that plugs onto the back) is accidently knocked. Yes, I've done it myself and I think most techs have. The 9" CRT nipple is quite a delicate beast.
 
Thank you all for your help. Unfortunately, it was the CRT "nipple" and I guess I need to replace the CRT. I might just sell it for parts, everything else was working fine.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.