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Electronics => Beginners => Topic started by: mattstats19 on November 24, 2023, 01:44:33 pm

Title: not an electrician but maybe you can help me?
Post by: mattstats19 on November 24, 2023, 01:44:33 pm
I work on unique art piecies and was wondering if there was a way to get this screen to light up?
Even white noise static would be great!
Hope the pic's help
Thank you so very very much
!
Title: Re: not an electrician but maybe you can help me?
Post by: BeBuLamar on November 24, 2023, 02:08:03 pm
It's not easy and dangerous. It involves using high voltage 15,000V or so.
Title: Re: not an electrician but maybe you can help me?
Post by: wasedadoc on November 24, 2023, 02:26:08 pm
I work on unique art piecies and was wondering if there was a way to get this screen to light up?
Even white noise static would be great!
Hope the pic's help
Thank you so very very much
!
No, that is just the tube and scan coils.  it won't even light up without several voltages between 6.3 Volts and about 15000 Volts plus drive circuits to the horizontal and vertical scan coils.  Basically you need almost all of the monitor or TV that it came out of.

Also that tube is vacuum inside and should be handled extremely carefully to avoid implosion and pieces of glass flying everywhere.

Get someone who knows what they are doing to dispose of it properly,
Title: Re: not an electrician but maybe you can help me?
Post by: CaptDon on November 24, 2023, 02:30:56 pm
A small cathode ray tube like that would probably produce usable screen brightness at maybe 2000 volts or so from a little 12 volt powered oscillator and a series voltage multiplier made from disk ceramic capacitors and diodes. The filament probably needs 6.3 volts at around .15 amps. In addition you may need some focus voltage around 200-300 volts HOWEVER a focused dot in one place on the screen will burn the phosphor in short order. You would be best to have the beam widely unfocused until it looks like a 1" diameter ball. The CRT still has a yoke attached to it for deflecting the beam. You could perhaps couple about 1 or 2 watts of audio into one winding of the yoke and capacitor couple to the other yoke winding to get some phase shift and get a pattern on the screen. Two separate unrelated audio streams, one feeding the vertical part of the yoke and the other feeding the horizontal part of the yoke would produce random patterns on the screen. In that case you would want to bring the beam into a better focus. You should contact a local ham radio club or perhaps some sort of local electronics parts store who could get you hooked up with local electronics hobbyists that could help you build it. There are getting to be less and less 'hands on' experimenters anymore. Everyone is a 'book smart' college educated engineer with no clue how to tackle something like your project, yet is a simple basic level. Maybe you could find a technician at a local electronics / audio / television repair store who would help you if you give them some credit in assisting you if you put your 'artwork' on display.
There was one guy here on EEV that ressurected a little CRT viewfinder from a camera to make a tiny N.T.S.C. monitor just for fun.
Title: Re: not an electrician but maybe you can help me?
Post by: Andy Chee on November 24, 2023, 02:31:08 pm
Getting a picture tube going is not a beginner’s project.

That said, if you only had the tube and required some electronics to drive it, you could buy a board from Ali Express like Adrian did here:

https://youtube.com/watch?v=MoqflFfvkR0

Or for a smaller picture tube:

https://youtube.com/watch?v=8cU9x23w4YE
Title: Re: not an electrician but maybe you can help me?
Post by: BeBuLamar on November 24, 2023, 03:33:23 pm
While a tablet of similar (slightly larger) wouldn't be too expensive and you can make it displays something. Of course the tablet LCD is flat I perhaps you can still get the rounded corner and make it looks OK.
Title: Re: not an electrician but maybe you can help me?
Post by: Doctorandus_P on November 26, 2023, 12:46:41 pm
You can be glad that the thing on the other end of that big fat red wire is missing. It's a lot safer that way  :)

If you want this thing to light up, then put on some safety glasses and use either a small hammer or a plier to break off the back end of the glass. Throwing a towel or other sort of cloth over the back end before you smash the glass also makes it a bit safer. There is vacuum inside, but that ain't too bad as long as you only break the thin tube on the back end. When I was a kid I thought about smashing the front of a (big) monitor with a sledge hammer but I never dared to do that. I still don't know what sort of risks there are for that, but just smashing the thin tube on the end is not too bad. . After the back part is broken off you can put some LED's inside, but do think about something to manage the sharp edges of the glass, for example glue some cardboard around it.

Releasing the vacuum will probably also damage the phosphor inside, but the phosphor will probably also block a lot of the light from the LED's, so when it's damaged you probably get more light out of it. If it was a color monitor, there is also a shadow mask inside,  The shadow mask is a metal sheet with small holes. You can try tearing it apart from the back side with a metal rod with a hook bend on the end.

Title: Re: not an electrician but maybe you can help me?
Post by: BeBuLamar on November 26, 2023, 02:39:50 pm
Any way it is a task that a true electrician wouldn't know how to do. I mean even a journey man electrician but has no interest in TV and electronics wouldn't know how. You will be surprised that many professional electricians wouldn't want to deal with a TV.
Title: Re: not an electrician but maybe you can help me?
Post by: shapirus on November 26, 2023, 05:43:20 pm
After the back part is broken off you can put some LED's inside
UV LEDs I would say. These screens glow when they are hit with UV light.
Title: Re: not an electrician but maybe you can help me?
Post by: Gyro on November 26, 2023, 06:59:59 pm
...

If you want this thing to light up, then put on some safety glasses and use either a small hammer or a plier to break off the back end of the glass. Throwing a towel or other sort of cloth over the back end before you smash the glass also makes it a bit safer. There is vacuum inside, but that ain't too bad as long as you only break the thin tube on the back end. When I was a kid I thought about smashing the front of a (big) monitor with a sledge hammer but I never dared to do that. I still don't know what sort of risks there are for that, but just smashing the thin tube on the end is not too bad...

The safest way I've found is to gently run a fine hand drill through the center of the metal anode cap. This gives a nice controlled vacuum release and no glass shards to pick up.
Title: Re: not an electrician but maybe you can help me?
Post by: CaptDon on November 27, 2023, 08:19:02 pm
Bad advice to drill the anode cup. You are working in the most dangerous area of the C.R.T. if things go bad!! Nipping off the nipple at the end of the neck is the safest by far and usually won't disturb the phosphor as the inrush air is dispersed by the gun. I would much rather see the C.R.T. remain intact and have some sort of electronics hobbyist help the O.P. get the tube lit and focused and apply unrelated signals to the H and V windings on the yoke to produce patterns!!! After all, the guy claims to be an artist. He could have a really captivating display of motion and patterns. Damn shame that none of the $100K+ per year electronics 'engineers' I worked with could make this project work. All a person would really need is a transformer from an old Eico 460 scope or any of the old vintage 'recurrent sweep' scopes that get thrown in dumpsters every day. For that matter, if the O.P. found a working dinosaur of a scope he could play with patterns on it and use 'External Horz. Input' and normal Vert. input to produce exactly the types of patterns I speak of. Saw my nephew nearly poop his pants when he dropped an old 25" color C.R.T. face down into an empty steel dumpster!!! Neighbors actually came out of their houses to investigate!!!
Title: Re: not an electrician but maybe you can help me?
Post by: arjen on May 28, 2024, 02:34:52 pm
This whole thing seems a bit dangerous. Still better to ask a specialist to help you, or ask step by step what you need to do. I did a few things at home related to electricity but I don't really bother, once I left the whole street without light, hahah, and since then I've learned to mind.

I think that everyone should do their job, and if you don't know something, it's better not to try. If I need some help, I go to a [spam link removed] local electrician in Sydney and I don't waste any time or create additional problems on my head. Last time the guys worked carefully and quickly, I was satisfied.
Title: Re: not an electrician but maybe you can help me?
Post by: coromonadalix on May 28, 2024, 03:03:43 pm
the red high voltage cable on the tube is cutted   why ???? 

who as done this kind of butchering,  this is a serious security risk,  this cable can be politely removed

this is not a patchable cable,  you have to change the flyback transformer ??     


Stop playing in this and trash this thing
   even i  with tv experience would not play in this 
Title: Re: not an electrician but maybe you can help me?
Post by: Gyro on May 28, 2024, 03:13:04 pm
A bit of a necropost. The OP only posted once (last year), I doubt he will come back now.
Title: Re: not an electrician but maybe you can help me?
Post by: Zucca on May 29, 2024, 06:41:03 pm
A bit of a necropost. The OP only posted once (last year), I doubt he will come back now.

Let's hope the OP is still alive.
Title: Re: not an electrician but maybe you can help me?
Post by: Terry Bites on May 30, 2024, 03:05:09 pm
1. Neck the Tube- Take care.
2. Cut off the gun assembly -take care. Round Edges off with a blow torch.
3. Stuff Some UV LEDS up its clacker.