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CRT substitution

I have my sister a brand new 14" VGA monitor well over 10 years ago. I believe she still has it in storage out near Punxatawney, PA (I know I must have botched the spelling up). If she ever retrieves all her crap, I suppose I'll try sticking the guts in an NCR PC4 I have sitting in storage (it's mono). For fun. The biggest challenge will be altering it to accept ttl video information.
 
vwestlife said:
A lot of vintage computer monitors were really just tunerless TV sets, making CRT replacement trivial -- find a CRT from a similar TV set and swap it in. Even if the monitor uses a higher scanning rate than the broadcast TV standard, it can be made to work; a CRT is just a piece of glass and metal -- it's up to the electronics that drive it to handle whatever scanning rate is being used.

For example, a lot of older low-end VGA monitors still only used a television-grade CRT, with a large dot pitch and non-anti-glare screen; they just increased the scanning rate to get it to display a VGA signal, causing a grainy image and lots of eyestrain (for example, the IBM 8512 and Tandy VGM-220).
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A TV CRT would make a poor choice for most computer monitors. Even the lowly IBM 8512 (which is just about the worst VGA monitor I've seen) still uses a significantly better than TV grade CRT. The only monitors I've seen with a TV grade CRT are cheap CGA monitors and ones aimed at systems like a Commodore 64. I actually just swapped a CRT from a 1980's Emerson TV into my Commodore 1702 to replace a badly scratched one.

A TV yoke will never be able to scan at 31.5 kHz, and it's unlikely that the VGA yoke will be compatible with the gun in a TV CRT. Also, most 13" TVs use a smaller diameter neck than most EGA or VGA monitors. Considering that surplus 14" VGA monitors aren't exactly rare, there's no real need to bother trying to make a TV CRT work.
 
andy said:
A TV CRT would make a poor choice for most computer monitors. Even the lowly IBM 8512 (which is just about the worst VGA monitor I've seen) still uses a significantly better than TV grade CRT. The only monitors I've seen with a TV grade CRT are cheap CGA monitors and ones aimed at systems like a Commodore 64. I actually just swapped a CRT from a 1980's Emerson TV into my Commodore 1702 to replace a badly scratched one.

A TV yoke will never be able to scan at 31.5 kHz, and it's unlikely that the VGA yoke will be compatible with the gun in a TV CRT. Also, most 13" TVs use a smaller diameter neck than most EGA or VGA monitors. Considering that surplus 14" VGA monitors aren't exactly rare, there's no real need to bother trying to make a TV CRT work.
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The IBM 8512 wasn't so bad, with I believe a 0.41 mm dot pitch (but still larger than IBM's own CGA monitors had!) but the aforementioned Tandy VGA monitor had a 0.52 mm dot pitch and looked as bad as a cheap Emerson CGA monitor attempting to display VGA resolution. At 640x480 resolution, the dot pitch was larger than the pixels it was supposed to display!
 
oh really? Try finding a decent 12-14" VGA monitor in News Jersey. Not interested in ps/2 stuff either, too grainy. I'm not seeing them, thrift stores don't want them. If you can tell me where to go, I'm all ears.

The earlier 400 line monitors by Mitsubishi and NEC (and many others) beat the pants off of the 8512 in terms of clarity. Granted the 8512 may have been brighter. I've never owned a color model 25, but I seem to recall it's display being fairly decent.
 
I've got several 12" - 19" VGAs. Various manufacturers. One is a 14" NEC Multisync (the original NEC Multisync). You can take your pick.
 
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