SE - Crackling noise and blank screen.

[LCGuy]

Check Scott's stickied thread on CRTs - the compacts used CRTs made by both Clinton Electronics and Samsung.

 

[Scott Baret]

If you've got an SE there's about a 50/50 chance of having one or the other from my observations. The Samsungs are rare in Classics and Pluses/pre-Pluses. As I mentioned in my stickied CRT thread there is no functional difference between the two manufacturers although the Samsungs do have a different hue of white to them than their Clinton counterparts. You can only tell this difference if you place it next to a Clinton. If you compare geometry problems between the two there is no advantage to either side--most of these CRTs are actually pretty good in terms of geometry and don't distort themselves over time like Trinitrons tend to do (I've seen a lot of Hi-Res Apple monitors and Color Classics that need geometric adjustments, far more than I've seen the shadow mask 12" display or the compacts).

I recommend only swapping the CRT with a fully compatible "Type A" or "Type B" counterpart (my taxonomy is explained in the stickied thread). All SEs use "Type A" and the best bet is to pull one from an SE or other "Type A" CRT machine that is being parted out.

If you're diagnosing SEs and want to see if a CRT is good or not, make sure you are using a problem-free analog board. Screen jitters, noise, and low brightness are almost always caused by a bad analog board and not the CRT itself.

Also, the SE self-discharges its CRT when the power switch is turned off and the machine is unplugged from the wall. To be safe, though, I always use an insulated pair of pliers to remove the anode cap (the red suction cup-type connector on the left side of the CRT when looking at it from behind). This is the part that can electrocute you when the machine is turned on/plugged in. Some play it safe and discharge the CRT; I find that the self-discharging mechanism in the SE and Classic do not necessitate this procedure. Replacing the CRT is fairly straightforward; once you get a replacement let me know and I can walk you through it (let me know if you want me to send a video tutorial on how to do it, as I can record one during my SE parting-out sessions).

 

[tomlee59]

Just out of curiosity, regarding all this thread, didn't Apple have more than one manufacturer for the CRTs? I'm thinking something like that wouldn't be any different of a situation as the iMac G3 did. On some iMac G3s, Apple had LG and I think Samsung making the tubes, but both had to match with the PAV Board inside those machines.
Again, just curious as to whether it applies. I'd hate to see someone putting in a generic tube that was claimed matching to a specific model of compact Mac and suddenly things start going wrong after installation.

73s de Phreakout. :rambo:

Scott's already answered, but I'll just add some repetition: All CRTs are fully interchangeable electrically among the compact Macs. There are electrical differences among the deflection yokes, however. So, to be safe, swap only the CRTs, and leave the yokes with the analog board.

Back in the day when Gamba was with us (RIP, Gamba), he noted that the pins on some CRTs were rotated 180 or so degrees. In some cases, the connector rotation occasioned by this arrangement ate up enough slack to force the lengthening of one or more wires.

Finally, as Scott has noted, different manufacturers used slightly different phosphor recipes, so there is a difference in the color of the raster among the different types.

 

[Mars478]

Back in the day when Gamba was with us (RIP, Gamba.)

Wait what happened to him?

 

[tomlee59]

Tragically, Gamba took his own life. Wally learned this sad news from Gamba's sister. She has been keeping his site going, as I understand it, although it is unclear for how much longer.

 

[ditty93]

I have finally removed the screen - ready for when i find a new one

It looks so hollow

Ditty93