The glorious Apple //c monochrome monitor. Compact. Solid. Heavy. Beefcake. These are the words used to describe this beast. We go ahead and adjust some settings on the yoke with a near-enough, good-enough mentality. We’re not perfectionists here, that’s for sure!

I’ve no idea where this particular monitor originally came from, although somebody has very thoughtfully engraved their details into it. That seems to have been quite the thing to do with Apple hardware back in the 1980s. The monitor also carries a manufacture date from late August 1984, so it has certainly been around for a while!

The picture was giving me trouble, with roughly an inch of unused space at the top of the screen. That’s about 2.5 cm for those of us living in the wonderful world of metric measurements. The usual external adjustments weren’t enough to get everything where I wanted it, so I investigated the centering rings around the CRT yoke.

I used a plastic knitting needle while working near the adjustment area. Moving the rings shifted the picture into a more useful position. Unfortunately, correcting the top also changed where the image sat horizontally. It’s one of those annoying situations where fixing one thing makes another part of the picture look a little less impressive.

I was using a Raspberry Pi as a video source, with a suitable AV cable I’d found amongst my collection of miscellaneous leads. I even had a look at the old Pepper the Dog Blog while testing the display. Naturally, Pepper’s blog provided some excellent material for seeing just how the monitor handled text and graphics.

The picture was certainly better by the end of the experiment, but I still had a gap down the right-hand side. There was also a little distortion around the edges, and I couldn’t quite find a combination of adjustments that made everything perfect. Move the picture one way and something else ended up too close to the edge.

The picture can be near-enough, good-enough; CRT safety needs more care. There are hazardous high voltages inside, and charge can remain after the power is removed. Don’t copy the yoke adjustments unless you know your way around CRT servicing.

I’m pleased that I managed to improve the alignment, even if this old beast is still a little crooked. It looks much better than it did when I started, and that’s good enough for the moment. One day I might have another go at getting that final gap sorted out.

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