CRT compatibility

[iantm]

I want to pick up at least one spare CRT in case something ever goes amiss, now that I've been reminded that CRTs in general are no longer being produced. I kinda knew that, but just didn't think about it, and what I don't want is to someday have to replace it and find out — there just aren't any.

But I'm not sure what to get on eBay. I know what the CRTs and connectors look like from all the SEs and SE/30s I've pulled, but there are some that I'm finding that hav ea very different connector.

This was pulled from a Plus. I have several donor tube connectors like the one below. Is it safe to assume any of these CRTs will work, provided I have a spare tub connection? I'm assuming that the one in the photo above will not work, because it's designed for a Plus.

 

[Garrett]

The CRTs themselves are all interchangeable from the 128k through the Classic II. What is not interchangeable are the yokes and neck boards. If you have a dead tube, you'll have to swap over the neck board and yoke assembly from the destination machine.

There's a caveat though - if you move yokes between tubes, the geometry will likely be off. The magnets spaced around the yoke are configured at the factory for a specific tube, and if you swap tubes, that image alignment will have to be done again. I've done it, but it's super time consuming and you may drive yourself crazy in the process.

To avoid having to readjust the yoke magnets, I did try to re-pin the yoke connector to use a tube from a Mac Classic in an SE, and found that the yokes were still not compatible despite putting the right connector on the end. Must be a different amount of windings. I hope this knowledge is useful in your search for a spare CRT!

 

[iantm]

I figured it would be something of that sort… not immediately transplantable. I ended up finding one the same yoke connector (not the smaller white connected above) so I'm confident it'll work out of the box.

Either way, good to confirm the complexity of it.