--- Gerald Uhlan <[EMAIL PROTECTED]> wrote: > I just purchased a used Snow CRT iMac (Summer 2001), > and the screen is > blurry in the center (but sharp on the edges). It's > also fairly dark, > even with the brightness all the way up. The > picture is also slightly > crooked, and the rotation control in the Geometry > preferences doesn't > do anything. Did I just buy a $425 lemon, or is it > possible to adjust > the focus and brightness somewhere on the inside? > Or, is it possible > to replace the monitor with the one from my > Blueberry 333? That > monitor is bright and sharp. I can live with it > being slightly > crooked, but not dull and blurry. Otherwise, this > is a great little > machine. > > Gerry >
This sounds similar to a 350 Blueberry I got off ebay a year or so ago. Except in my case all three electron guns "seemed" out of whack. The right side of the monitor was fine but the left side bowed in about and inch in a concave curve which threw everything out of register. After researching a bit many people said the analog board was probably bad. I was looking at getting one on ebay and researched on how to change it since the CRT can kill you if you aren't careful. I used to work on the radar system of an F-4 Phantom so I'd dealt with much more voltage than that so I wasn't scared off. I've got a pdf I found that shows how to properly discharge the CRT if you are interested in messing with this yourself.... though how I fixed it really isn't safe...thats your warning... I'm not sure which came first the chicken or the egg in this case... but I took it apart and on the back of the CRT there are little plastic fins... 6 of them.. 2 for each electron gun. Normally they have a bead of glue or paint or something going down them so you can't change their position. I noticed that they had been moved.. probably by the guy who had the machine before me. There are also two potentiomers (little black twisty things ;D) on the left side of the CRT on the power control board I believe that are kind of a master brightnes and contrast from what I could gather by testing, and finally there are several little adjustment screws on a circuit board on the back of the CRT. By keeping it on and making little adjustments to the fins on the back and the little adjustment screws I was able to get a pretty good picture with only a few minor shocks ;D. There is 110 running on that little board on the back and when you keep making minor adjustments then looking at the front to see what happened you have to be very careful or you'll get little shocks. In any case I got it to what I could live with because I didn't want to have wasted $280. Then I decided to try putting on Jaguar just for the heck of it and had to update the firmware first. After I updated the firmware the brightness on the screen was way too bright and I couldn't see anything really until I turned back down the master brightness and contrast on the left side and the screen was almost perfect again. This reminded me of posts I'd read on the internet that said that some people had "killed" their iMacs by installing X without updating firmware. My monitor would have appeared dead or at least very dark if the previous owner hadn't tried to fix it himself. After updating the firmware I had to go back and make a few minor adjustments to the screws on the back to align the RGB guns again to perfection and now I've got a perfect iMac. Since then I've seen several iMacs on Ebay with the same problem. They usually go for a lot less if the owner actually lets you know that the monitor is messed up. So in my case some owner sometime in the past must have tried to put X on and "killed" their iMac. Either that same owner or perhaps the one who sold it to me attempted to fix it and broke that glue seal on those plastic fins making it good enough to sell again to the next sucker... me. I don't remember for sure but I'm pretty sure that the snow iMac didn't come stock with X... I know X came out right around that time but if it didn't perhaps the same thing would help you. Go to apples site and check on all the firmware updates. Make sure yours is up to date. Hopefully its an easy software only fix. If not.. and you are not afraid to tinker with it you can check what I mentioned above... once again be careful. I can dig up that pdf that shows where the 10,000 volts is so you can avoid that area.... because that part can kill you. Never can tell what the previous owner tried so might want to at least look at those areas to see if they have been messed with. Matt aka HamletUSMC Bondi iMac/333 Blueberry iMac/350 Powerbook 3400/180 http://geocities.com/hamletusmc/ __________________________________ Do you Yahoo!? Get better spam protection with Yahoo! Mail. http://antispam.yahoo.com/tools -- The iMac List is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | - Epson Stylus Color 580 Printers - new at $69 | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> iMac List info: <http://lowendmac.com/imac/list.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/imac-list%40mail.maclaunch.com/> --------------------------------------------------------------- >The Think Different Store http://www.ThinkDifferentStore.com ---------------------------------------------------------------
