WYSE-60 Dumb Terminal CRT - ghosting/trails?


This is a WYSE-60 dumb terminal - “paper white” video color. It seems like
there is excessive ghosting or “trails”. See this video, take note of the
right hand side (file names scrolling).


I had this exact model of terminal (but a different unit) > 20 years ago, and
I never remember ghosting like this. Is this just normal for something of
this age ? Is there some component that could be replaced or adjusted to
mitigate or solve this ?


Welcome! Looks to me like “normal” phosphor persistence. It might be that there’s an ageing effect, which would be a chemical thing and a property of the phosphor layer on the inside of the tube. I can think of no electronic cause of what we see there, because it is essentially after-image, and I see no way for display electronics to do that.

I assume the video is showing pretty much what you’d see by eye? Is the brightness or contrast turned up much more than it would normally be?

Thanks for the reply.

The brightness is cranked 100%. No contrast control on these guys. I will play with brightness a bit (although I really like it at 100%) to see a difference.

As for remembering the one I had 20+ years ago - could be rose colored glasses and fading memory :slight_smile:

It might be that turning it down will make a big difference. These days we tend to look at large rectangles of bright white light, with dark pixels, and perhaps are accustomed to a high average brightness. As I recall, we wouldn’t operate VDUs at max brightness. Indeed, we’d try to dim our office lighting where we could, and turn the brightness down. (Office lighting is optimised for reading dark print on light paper, and office life isn’t like that any more!)

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I guess, it’s still an aging effect, but not because the persistance of the phosphor had dramatically changed (I wouldn’t know of a mechanism for this), but the CRT is probably a bit “tired”, therefor max brightness.

I’m guessing 100% brightness is the reason – the amount of energy in the phosphors is just super high! You’ll probably find that turning the brightness down 15 or 25% doesn’t affect the perceived brightness significantly, but helps with halo and persistence effects.

There is probably a contrast control internal to the monitor, which (due to the aging effects that @NoLand mentions making the CRT “tired”) may benefit from a tweak. There are, of course, very high and dangerous voltages inside a CRT!

I have a Wyse-60 myself and I don’t think it has as much phosphor persistence as that one has, however it’s a somewhat traditional green colour than the paper-white ones…

Fast forward it a bit to get to some scrolly bits, but there’s not a lot of persistence visible there that I can see.

(It’s currently waiting to be unpacked so I can’t run it up right now)


Hah - I just watched your video the other day trying to compare. And I agree you have much less persistence than Im having with this one.

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Looks very much like Gordon is filming in a fairly dim room, whereas you are somewhere quite bright - more evidence that your brightness will be cranked up much higher.

I seem to have decades of persistence on this Model 35, though…


Nice - yeah I’d say you have most/all of us beat with that one :rofl:

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