Slotload iMac with ghosting on screen

[wesli_1]

I have been given an old slot-load (350/20G/128Mb) iMac, which works perfectly apart from the screen.

The image on the screen appears to be ghosting (similar to on an analogue TV set), and I think it may be caused by incorrect synchronization of the video signal going into the CRT. The entire picture also has a heavy blue tinge to it, and the picture does not extend to the left & right sides of the screen (ie there are black borders on either side of the screen, about 2-3cm wide.)

any ideas?

Cheers :-)

[Finiksa]

Are the symptoms, Bright washed out display, Sides of display contracting inwards. Is there a bright narrow vertical band along the middle of the screen? does the image "wobble" when the HDD or optical drive are being accessed?

If so, it sounds like you have a failing Power Analogue Video Board (PAV) that will need to be replaced.

[Macmaniac]

Sounds like PAV board symptoms to me, have a tech look at it, it will probably require a new PAV board which can run from $100-$200. Sometimes it can be your CRT tube, but it is usually the PAV.

[wesli_1]

Are the symptoms, Bright washed out display, Sides of display contracting inwards. Is there a bright narrow vertical band along the middle of the screen? does the image "wobble" when the HDD or optical drive are being accessed?

Yes, the symptoms were similar to those. But guess what? I switched it on again this morning, and the symptoms were gone! I have switched it on and off a few times, and it has still been running fine. Might have been dry joints on the PAV board or something.

Thanks for your help guys :-)