NeXT 17" Megapixel Monitor in central Germany to sell or trade. The monitor powers on, but I have no NeXT Computer to check the image quality. Last used in 2009. At the time, monitor was bright and in focus. I kept the monitor as a backup for my NeXT Station. I have since sold all my other NeXT hardware and it would be a shame to dispose a working megapixel. Due to weight, size, please pick up only.
http://kleinanzeigen.ebay.de/anzeigen/s-anzeige/next-17-megapixel-farbmonitor/271112219-228-2852?utm_source=email&utm_medium=system_email&utm_campaign=email-SendAdToFriend&utm_content=ViewAd
I regret dumping mine for space. I'd take it but....you're a little far to drive to. :wink:
Don't worry, it's not going to waste. I'll keep it until I find a good home for it.
Just curious, has anyone ever successfully swapped out the CRT on a dim megapixel? As long as the CRT had the same frequency, voltage and can do the proper resolution, it should work, even if it's not 100% pin compatible. I'm old enough to know than in TV repair, swapping out the CRT was not that difficult to do as long as you discharged the flyback transformer first and took good safety precautions. That was back when TVs were expected to last 10 or 20 years and went through multiple tubes during that lifetime.
I guess the trick would be to find a beige monitor that used the same tube and is still available in large(r) numbers than the megapixel.
I don't seem to recall what tubes could be subbed in on the mono megapixels (and being big AND monochrome means that you will not be finding replacements easily) but I know that the color megapixels were mainly rebranded Hitachi and Sony monitors and their tubes can very easily be sourced form other monitors.
Actually, now that I think about it the monochrome tubes might be decent candidates for rebuilding if we find out the tubes will cost far more than the often $800+ rebuild jobs that replace the entire gun assembly.
QuoteActually, now that I think about it the monochrome tubes might be decent candidates for rebuilding if we find out the tubes will cost far more than the often $800+ rebuild jobs that replace the entire gun assembly.
Wow, I wasn't aware that it's possible to rebuild a CRT. That would be interesting to see if anyone finds a source for rebuilding monochrome CRTs.
There's ONE place in North America officially that still does is and they're slowly rebuilding the operation after relocating. Europe apparently lost their last remaining rebuild service a few years ago but I'm sure there is still a place or two hiding in the former soviet states.
I thought the issue with the mono MegaPixels was that the phosphor coating on the tube inner face loses it's potency(?) over time, vs. being an issue with the gun assembly.
According to the NeXT faq it's the cathode material -
5.44 What makes aged NeXT monitors dim?
monitor, dim
The cause of the dimming monitors is the CRT cathode wearing out. The
most common type of CRT (and the type used in most NeXT monochrome
monitors and all of the NeXT color monitors) uses what is called an
oxide cathode. A thin coating of oxide is deposited on the cathode to
allow the electronics which form the picture to get off the cathode
easily. The oxide gradually boils off the cathode itself, and when the
oxide is gone, the CRT goes dim.
Typically, the oxide will last from 10,000 to 20,000 power on hours
(screen savers don't help the cathode, they only prevent phosphor
aging). Unfortunately, the black monochrome monitors fall into the
short end of the life range thanks to Toshiba who made the CRT's. The
aging is more noticeable in Unix machines because they tend to be left
on. Note that there are about 8,000 hours in a year. If you leave your
monitor on all the time, all oxide type CRTs will be dim in three
years.
The other type of CRT cathode is the I-cathode or dispenser type. This
type of cathode is porous and continually brings new activation
material to the surface. Its lifetime is 40,000 hours or more. The
last of the NeXT monochrome monitors (N4000B) used this type of CRT
and they don't go dim. There aren't many of that type around because
NeXT quit the hardware business after producing only a few thousand.
If you can get an N4000B monitor, you won't ever have to worry about a
dim monitor.
Many manufacturers are going to dispenser cathode type CRTs in their
monitors with Panasonic leading the way. The best advice is to turn
off the monitor when not in use. If that is impractical, try to
purchase one with the long life cathode.
Spherical Solutions (smg@orb.com) has a supply of new N4000B long life
monitors for sale in either ADB or non-ADB configurations. If you need
to repair or replace a monochrome monitor, that is by far the best
type to use.
If you read this far, you probably know more than you ever wanted to
about CRT aging, but I hope this helps.
Hi Guys,
I recently refurbished an original N4000 monitor.
CRT is still surprisingly bright and sufficiently crisp for the age and model, however I started noticing visible "smearing to the right" next, for example, to windows' frame upper corner. I guess you know what I'm talking about. I made some search on google, but could not find any clear answer in regard to the root cause of this problem and therefore in regard to how to fix it. Some say capacitors, some other connector shielding (I'm using the original cables), some other the yoke circuit, many just categorize it under "aging CRT".
Does anyone have any suggestion and "quick fix" (e.g. recapping) for this issue on this model, or shall I assume it's just the aging and live with it?
Thanks in advance for feedback.
Hi Paolo,
In my experience this is not fixed by caps. I think the problem is with the tube. You can maybe help by adjusting the cuttoff pot.
Hi Brian,
Thanks for the feedback, I will desist from recapping the CRT boards.
I adjusted the cutoff, gives some barely noticeable improvement.
I also tried different cables, no different.
Anyhow, the monitor is still perfectly usable for being a 31 yrs old piece of equipment, it has all the rights not to be perfect, so this will be it.
Check for oxidation on the tubes pins. You want them to be nice and shiny.