512k Display Swap - Can I use any Classic Mac Display Tube ?

[MacOS]

Hi Folks,

I have a Mac 512k with a spoiled desktop on the screen.

The Trash Corner is lower than the left lower corner and the corners are unsharp while the center is sharp.

Is the problem the display itself and can I use any tube from the classic line to swap the old display tube? So can I look for any defect Classic Mac to save my 512K?

greetings,

MacOS - http://www.myoldmac.net

 

[Mac128]

Yes you can use any classic Mac 9" CRT (except the Color Classic) to replace any other. However, it sounds more like you have some adjustment issues, which members of this forum can be of further help in diagnosing and repairing. Keep in mind if it is an adjustment issue, something caused it to go out of adjustment, most likely shrinking capacitors and other failing analogue board parts. This is a good place to start: http://68kmla.org/files/

 

[Scott Baret]

Read the FAQ on CRTs in this forum. If you're using a black and white classic it may or may not be interchangeable depending on if you have the Revision A or Revision B analog board/CRT in your Classic. (Revision A will work in a 512K).

However, your problem sounds more like an issue with the focus on your machine. You'll need a TV adjustment tool (you can find these at Radio Shack) to adjust the knob on the side of the analog board that controls the focus. CRTs tend to need this adjustment once they hit ten years of age--I had it happen with a TV and have seen it on over 50% of the compact Macs I've worked on lately.

 

[MacOS]

Thank you for the infos, I will open the 512k and try to adjust the screen.

Get back to you later.