iMac display has rotated!

[Baggy]

I changed a dying hard drive in a 350mhz iMac, all was well, installed new 9.2.1, all was well. Rebooted to hard drive to finish reinstalling 9.2.2 and software and window was rotated about 5 degrees clockwise. Strange I thought so went to Monitors and Geometry to put it back, but to no avail, it would only turn it back about 2 degrees.
I put in the Apple G3 Pro test disk to use the Display Utility (didn't strip it down to use the cable) to see if that had enough capacity to return it to normal, but not much difference there either.
I reset nvram and all in open firmware and still no difference.

Any suggestions? Other than a book under the right side of the iMac to level up the screen?!

[unclemac]

Hi bags,

I have seen this too, especially while transporting imacs and they get bounced around a bit... Don't have a real answer though.

I am assuming that the gun (or whatever that thingy is called at the back of the CRT that projects the image is called) wiggles a bit and is prone to being knocked out of alignment when it is bumped or shaken, and comes out of alignment more than the Geometry feature can adjust for.

My solution? Take the imac for ride around the block. Don't laugh! Sometimes it actully works.

Maybe someone else has a more elegant soluition...

[ricks]

Why can't we laugh?




Only you would think of SAYING that. There are a few that would do it.

[Baggy]

So does that mean that I should get it back out of the car?

[unclemac]

Laugh away....

I was about 3/4 serious. I have seen several places where folks use their imacs like a poorman's laptop - lugging them from place to place. And the geometry would bounce around with the moves; never got severely out of wack, but far enough that one could not adjust it level with software.

The next ride *might* fix it. And the weird thing was, this was not riding around in the back of a truck. It has happened while the imac was seat belted in the passenger's seat of nice cushy ridin' Buick or something like that. Hell, just moving it from desk to desk might actually affect it...

The CRT is very firmly anchored in the case, so I really can't see how anything but the gun can be shifting around, unless there is something internal in the CRT itself that can be bounced around too.

I am not one to subsribe to banging on machinery in general, unless it is a starter on an old dozer or something, but a few bounces might make a difference.

Hopefully not for the worse...

Or just tilt your head to the left a bit.

[ricks]

There is a bright side to this. Any socially responsible geek SHOULD have a tilted monitor. That keeps your head tilted to one side causing said geek to only drool out of one side of mouth instead of both. Much better social grace.

[kaye]

Baggy,

See what you started with these nut cakes? Wrapped around the neck of the tube is a thing called a yoke. It is held in place by a rubber wrapped clamp with screw tightener. That yoke is what rotates the picture. Be careful because there are voltages stored in there that will make you rotate. Also, only rotate, don't push the yoke further in on the neck or further out. Just rotate.

I don't know if the iMac will startup without the cover back on but it is a trial and error. I used to do it on TVs when they were running, but very carefully. As I recall, pushing in or pulling out will casue the three guns to disalign with the shadow mask holes. So be careful not to change that setting. Rotation of the yoke and direction of rotation is the same as what you are seeing. If you need to rotate clockwise to level the picture, then you need clockwise rotation of the yoke. If you need 5 degrees clockwise, then you rotate the yoke 5 degrees clockwise.

That's about all I recall. If you decide to do it, report back so that we know you are still with us. I hate it when folks die on me or at least need to use hair spray to mat their hair back down. k

[unclemac]

I prefer fruitcake.

See baggy? If you tell a silly enough story, someone who actually knows something can't stand it very long, and gives some real advice.

I can say that imacs run very nicely whilst spread across the work bench and upside down. Just keep conductive things like your fingers outa there.

I have a pile of parts handy so I will try to ID what Kaye if refering to.

Update: Don't see anything like what Kaye describes, but then I don't know what I am looking for....(and I am a nut cake too). The only thing I can see that looks adjustable is a bunch of rings down on the narrowest part of the neck that look like they could/should ne rotated, like focusing a zoom lens on a camera. Don't dare touch 'em cause there are like 6 or 8 of them.

Color(s), fosharpness, brightness, position(s), etc.???

Update update: OK, I kinda see it, but looks like a real job to loosen, rotate, and tighten. Really buried... If it were me, I might prop it up with a book afterall.

[kaye]

OK OK unc, you de fruitcake. That's giving you credit for driving an iMac around in your car. I worked with console TVs mostly and would have needed a hearse. The rest of de guys are nut cakes. k

[unclemac]

Yeah, now I just need a voltage converter so I can surf the web via airport when parked outside the local Starbucks... Would'nt that be a riot? Can you imagine the looks you'd get hunched over an a fruity colored imac in a parked car?

...I need to dig up an imac service manual and see if it addresses this calibration, as it does not *look* as though it is meant to be adjustable at all.

[Baggy]

Ah, we seem to be moving forward a little. As this is a client's mac I will try finding out on one of my own dead imacs first - just to see if I can also identify the bit that needs rotating.
I will of course report back as soon as I have frizzed my hair a little :-)

[Baggy]

I had a really nice surprise this afternoon, I was looking for an address in Oakham (UK) and pulled into a car park to check out with Route 66. I opened up my Pismo and had a little message appear "Would you like to connect to open Apple network.....?" So I answered in the affirmative and happily checked my emails and looked up the phone numbers of a few people before moving on again!
Shame everyone doesn't provide this facility - don't even know for sure whose network I had hooked into. It does raise the question though that not many people know how to keep their networks private - come to think of it, mine isn't either - how do you do that??? ..... new thread perhaps?

[unclemac]

Yes, new thread please!

Could be a fair amount to cover. Should go in Network and Security...might be something there already.