What's the point of aliexpress CRT board?

[Locke141]

what is the point of these CRT board?

I live in a part of the world where you can still buy new CRT TV and was wondering if I could find a tub to match one of these. I would think if its made with CRT's that are currently being manufactured in mind I Can't see two many different options.

[Ken Layton]

The "universal" style chassis like this are for people who want/need to replace a chassis that is no longer repairable, but the tube and yoke are still good.

The particular chassis in the link you posted requires operation from an isolation transformer. Even though it has a conventional power plug on the power cord, NEVER plug this chassis into a wall outlet or else it will be damaged immediately. The price shown in the link is excellent ($26).

[ChurchOfSolipsism]

According to everything I've read none of these things take more than a year to break.

[Ken Layton]

These boards have more adjustments (position, size, centering, etc) than say an Electrohome G07 ever had.

[Ken Layton]

According to everything I've read none of these things take more than a year to break.

Have you actually tried one of the chassis in that link?

Don't know who makes it. It's not a Wei-ya, Jen Shinn, Kortek or Rodotron chassis like we typically see. It appears to be from some new company. For $26 someone ought to get one and try it out.

[Locke141]

How do you do you know how to match it with a Tube?

I live in lao, there're a lot of places where you can buy a brand-new CRT very cheaply here. I don't really understand what a need to know.

[Locke141]

"universal"

Does that mean it can be used with mutable tubes?

Here is a the Tube in the CRT I have.

Edit: Reading about this one it sounds like you need to match the resistance to the Tube.

1) Measure the vertical ohms, it should be 6 ohms to 12 ohms, usually the yellow and green wires coming from the Yoke. If yours is not between 6-12 ohm this chassis will not work! (YOU WILL FRY IT IF NOT IN THIS RANGE!)
2) Measure the horizontal ohms, usually the red and blue wires. It should measure over 1.3 ohms. If not you can take a 5 to 10 watt 1 ohms resistor and add it in series to the circuit to increase the ohms to get it over 1.3.
120vac Isolation transformer is required.

But what about the nack pin out?

[Ken Layton]

If the neck diameter is 29mm this tube should work.

[Locke141]

Thanks,

I don't have to worry about yoke resistance?

I might give it a go after my trip to the US.

[Ken Layton]

Yes, you still need to worry about the yoke resistance/inductance. It needs to be within the specifications the chassis calls for.

[DeLuSioNal29]

Locke, give these videos a watch.  He explains it well.   

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DeL

[Locke141]

Thanks DeL,

They are actually how I new to ask.

After my home leave I'll find a new CRT, disassemble, take all my measurements then message the vendor and see what I get. If this works out I may try to make a AC Coupled so I could try hooking up my consuls to it as well.

[DeLuSioNal29]

And it goes without saying...  Don't forget to discharge them before tinkering. :-)

DeL

[buttersoft]

I've used a 14ohm tube with a nominal 10ohm chassis with a small mod to adjust vertical size. Seemed ok?