RE: BUSTED CRT TV

One of my faults is an over-inclination to pick up a topic that 
someone starts from an emotional perspective and take it full-on 
into a technical discussion that they have no interest in 
whatsoever. Unfortunately in real-life discussion this usually only 
becomes apparant to me after the other person immediately stops 
listening, or even talks over me at someone else. Here in 
Gopherspace I do have the time to see the mistake I'm making, but I 
can also simply imagine that people are really listening, so I can 
just ignore that and continue anyway. So in the case agk's recent 
diary entry about her CRT TV being broken, I will.
gopher://sdf.org/0/users/agk/phlog/2022-11-25-crt.txt

First though, I am very surprised that someone else in gopherspace 
still uses a CRT TV, I know others use CRT computer monitors 
(though perhaps not every day like me), but I figured I was 
probably alone on the TV front. Mine's much bigger than agk's (25" 
vs 13"), and probably a few years older, though without the 
built-in VCR (I never saw many of those in Australia).

I've already got some photos in the relevent section here from when 
I repaired it a few years ago too. The vertical deflection 
amplifier chip litterally blew up, leaving it only able to display 
one horizontal line on the screen, but believe it or not I was able 
to buy an exact replacement cheaply from an Australian electronics 
components supplier, no fuss at all. I also replaced a few caps as 
it was mentioned in an archived Usenet thread from the 2000s that 
this was a good idea for this model, and noticed that a serviceman 
sometime in its previous life had beaten me to a couple already.
gopher://aussies.space/1/%7efreet/photos/teardowns/NEC_TV_Repair/

More recently I've tried to work out a problem causing the 
brightness to dim on a CRT monitor that I used to use in place of 
the one I'm typing in front of now, but I am struggling more with 
that. It's probably the HV dipping, but the cause of that is 
time-consuming to narrow down without a schematic and with some 
part number obscured by heatsinks. Even as the electronics repair 
trade dies, the web unfortunately hasn't liberated all of its 
servicing documentation to the masses.

Agk's aging set was damaged from being knocked over by her 
daughter, which plays to all my hang-ups about children. But anyway 
it might be repairable if it's an electronics fault rather than 
damage to the CRT itself. Unfortunately it's true that nobody's 
going to do the repair these days. There's a critical mass of 
information and demand that's needed for mass-market electronics 
repair, before the extra time necessary due to lack of 
documentation and simple lack of familiarity makes it way too 
expensive, limiting its practicality to specialist applications 
such as the art installations that she mentions.

Nevertheless technically you _can_ still just buy a new one. Much 
to my amazement there are still Chinese sellers on Alibaba offering 
numerous models of CRT TVs, such as this one:
https://aipuda.en.alibaba.com/productgrouplist-213625037/CRT_TV.html

It seems unlikely that they're really still made, yet many of the 
models do seem to be newer-looking designs, so who knows? I've been 
tempted to order a sample just to see what turns up, but it's sure 
to cost many hundreds of dollars to send one here by courier. There 
are some hints that the export market is mainly Africa, though 
their advertised bulk prices (which I admit rarely have much actual 
meaning on Alibaba) are on par with similarly-sized LCD models, so 
it's hard to make sense of that:
https://aipuda.en.alibaba.com/productgrouplist-218059586/lcd_tv.html

If they really are still making CRTs, then replacements for old 
arcade machines is probably a better market that they're missing, 
and actually come to think of it this is a sector besides art where 
the CRT-monitor repair trade is still in operation, even in 
Australia. If only I knew someone into dealing with chinese 
manufacturers/wholesalers (I'm useless with it myself, I struggle 
with the chinglish and I'm pretty sure some rob me blind), there 
might be money to be made there.

Then of course there's the collectors/restorers of old sets. This 
is naturally more of a hobby DIY sort of deal, one that I'm still 
planning to get into myself one day with my grandparent's first TV 
from 1956. The limit of the hobby side though has always been the 
CRT itself - much like the chips in modern electronics, it's way 
beyond an individial electronics tinkerer to rebuild one. But CRT 
rebuilding was an established profession in the past, and there's a 
trueley facinating american video showing the last man in the 
business over there going through all the magical processes 
involved before he closed down in 2010. It's a very thorough and 
facinating video that I highly recommend to anyone truely 
interested:
https://www.youtube.com/watch?v=PFnWYe5MzrY

His equipment at least found its way to a group of DIY restorers. 
They also documented a CRT restoring place in france which takes 
things right down to the bare glass. Combined with the other video 
they together show a complete remanufacturing process, but 
unfortunately this latter video is unedited and rather slow to 
watch, especially with much of the chatter in french:
https://www.youtube.com/watch?v=byCeMKzPJgM

With all the complex steps involved, it might make one wonder how 
it was all done at scale. Unfortunately I never found a good film 
covering the inner workings of the fully-automated CRT 
manufacturing plants of the 90s and 2000s, in spite of much 
searching a few years ago, but there is this neat film showing how 
it was done in the 60s (two parts):
https://www.youtube.com/watch?v=Cf-rNlqeWw4
https://www.youtube.com/watch?v=QKvVE2jv5UQ

More rambling about documentaries coming soon, but I really had 
better get onto my election-day stuff.

 - The Free Thinker