SE/30 Blurry Tube?

[jpolster2009]

Hey I was going to buy this http://chicago.craigslist.org/nch/sys/2158040403.html

what causes a blurry tube and can I stick that motherboard into a classic and have it work?

 

[beachycove]

can I stick that motherboard into a classic and have it work?

No.

As for blurred screens, others more steeped than I in the lore of the Compacts will know better, but it could be a simple focus adjustment that is needed, or, more likely, a blurry screen like you get in one version of the so-called sisamimac problem, which requires some component level repair, and entails replacing the capacitors. Betchya $10 there's no sound from the machine in question, either.

 

[Bunsen]

You can stick it in an SE though. ISTR there may be a small amount of metal trimming involved on the internal chassis (widening one cable passthrough hole or something like that), but the two boards are otherwise compatible.

 

[tomlee59]

Hey I was going to buy this http://chicago.craigslist.org/nch/sys/2158040403.html what causes a blurry tube and can I stick that motherboard into a classic and have it work?

If the screen is bright, has good contrast but is blurry, it generally means that there is either a simple focus problem, or the brightness is simply cranked up too high. If the blurriness is actually jitter, that's often a symptom of capacitor-related problems, or loose connections. Both of these problems are common ailments in these compacts.

If the crt is dim and blurry, it could simply be worn out. The only practical fix is replacement of the crt itself. All compact Macs are good crt donors. To be safe, keep the yoke with the SE/30 and swap only the crt itself.

As Bunsen notes, you can put the SE/30's logic board into an SE with little trouble. However, you will not be able to put it into any other compact Mac without major work.

 

[trag]

There's a focus adjustment on the analog board. If that doesn't affect the focus, there's a fixed resister which sometimes fails open on the analog board. Replacing that resistor typically restores the focus adjustment to functionality, and then one can adjust the focus.

Look for one of Larry Pina's "Repair and Upgrade Secrets" books. There are one or two which cover the SE/30 amongst other machines.