Wei-ya chassis 56ohms high impedance , yoke adapt to match

Welcome to AA.

 

Link is fine, vid is appreciated. No idea about reversing that mod.

 

I picked up a couple of early 80's LAI lowboys last year, each with a 54/2R (or near that) yoked 20" tube. I think the 20" Samsung Hi-Tron TV-488 TV i picked up from the brutal-RGB mod-thread also had a similar yoke, but i'd need to check that. So they might not be that uncommon? Jomac would certainly know, but i'm sure a lot of other people on here would too.

CRT is finished. You will struggle changing yokes to ever get any sensible convergence or purity (purity is even colouring across the screen) again.

 

Time to go LCD

 

Welcome to AA

56/2 is fairly common....

Did you buy a chassis before you had a tube....

Normally done the other way around.. Find a tube then chase the chassis

Just get a new chassis to suit the tube, best person to speak to is @Jomac

 

Regards,

 

Johns-Arcade.

Yep, keep the CRT if you can, JOMAC used to provide high impedance chassis, not sure if he still does. If he does, it will be as simple as sending him the yoke readings od the tube and then he will match you a chassis.

Thanks

 

Thanks for the replys,

Buttersoft - I had a look at the values on a lai lowboy that I have here and it's values are 43.5 and 2.4 so would consider this high impedance yoke so you be onto something there like- arcade tubes are more likely to be high impedance and t.v tubes low.

Home pin - not a fan of lcd with crt type games I'm sorry. I beleave if the values are close that convergence of purity will be ok, but yes agree that finding a t.v tube that's high as 56 maybe a challenge.

Marty Moose- I usually purchase high quality chassis from jomac but the sharp image chassis he sells have been discontinued and he is nearly out so we all may need another option soon. When I purchased a heap of parts from my overseas supplier I thought I would give one of these things a go as it maybe us OG's crt fans only hope for the future.

I appreciate all your guys help but still chasing a answer about changing the yoke like on the video but opposite so going from low to high impedance

 

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Thanks but want to use chassis I have, Joey option nearly run out, or run out

 

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Hi john I think u sell new tubes for these chassis. U maybe able to sell me one as I don't want to import the miminium 8

 

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Namastepa-The chassis I have is high and crt low to clarify

If it is just one of these $30 jobs you hav then pretty sure 20" kortek(samsung) tube will do the job

If it is just one of these $30 jobs you hav then pretty sure 20" kortek(samsung) tube will do the job

 

Yes mate that's the one, ok so got a option of checking the dump for a Samsung tube, Awesome thanks mate.

Still looking for a answer on what he does in the video to be true and if it can be done in reverse. I would have to assume yes, if it ends up to have 56 and not heap higher or lower not sure.

Yes mate that's the one, ok so got a option of checking the dump for a Samsung tube, Awesome thanks mate.

Still looking for a answer on what he does in the video to be true and if it can be done in reverse. I would have to assume yes, if it ends up to have 56 and not heap higher or lower not sure.

 

The Samsung tube that was used on the Korteks has not been made for about 25 years so would have to come from an old machine.

I doubt they were ever used in TV's as most Arcade tubes were crap compared to ones used in TV's

The Samsung tube that was used on the Korteks has not been made for about 25 years so would have to come from an old machine.

I doubt they were ever used in TV's as most Arcade tubes were crap compared to ones used in TV's

 

Agree I also heard the arcade tubes were of bad quaility compared to the t.v tubes.

This may explain why all the tv tubes I use are low and the arcade tubes are high.

Wai- ya say universal and we all know this not to be the case and has been said for the doc(Joey) also.

Wai-ya maybe saying more universal as a replacement for your arcade tubes not to set up new chassis tv tube pair set.

Unfortunately as time goes on we will have mostly only t.v tubes left (hundreds at the dump) but limited arcade tubes and now the chassis for those tubes are running out what are we to do?

If changing that wire on the yoke makes that difference it could be our answer?

 

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The Samsung tube that was used on the Korteks has not been made for about 25 years so would have to come from an old machine.

I doubt they were ever used in TV's as most Arcade tubes were crap compared to ones used in TV's

 

Agree heard arcade tubes are worst quality.

Wei ya universal must be more likely to to suit replacement chassis for arcade rather then to be used to set up new tv tube with chassis pair.

Arcade tubes are rare, tv tubes are everywhere, the sharp imagine chassis from Joey to pair TV tubes with new chassis has run out, so what are we to do.

I can buy in 8 tubes at once minimum order with these chassis to suit. Or can we just change that wire around on the yoke like it the video so then we can use tv tubes

I'd say joey would have a alternative as its his business doing monitors

When I reply I start new threads sorry.

 

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he may have one left to do it, but what about next time

 

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Joey had x18 left on the 16/7/16 and said no more ever

When I reply I start new threads sorry.

 

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he may have one left to do it, but what about next time

 

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Joey had x18 left on the 16/7/16 and said no more ever

 

Interesting last couple I got wernt a sharp image

 

But that was a year or so ago

Yeah, didn't really even want the chassis as I had ordered coin mechs from them but they didn't have the type I wanted so seemed easier to swap for something else then work out refund and also thought well I'll give it ago, I thought these were more a universal for tv and arcade tubes alike but seem maybe for some common( not all) arcade tubes.

I'm still unsure if what was in the video is plausible and ok to do in reverse and know the man to ask is Joey. I have bought chassis off Joey in the past and he has helped me out with installing them. I have the most upmost respect for him and would normally ask him for help but in this case it was not appropriate as I have purchased from other sources and think he still may have some stock left, but like I said I didn't set out to buy another chassis type but now got one all the same. This is my first thread/ posts here and was hoping for a answer that wasn't ask Joey, at least doing this way Joey can reply at his own discression rather then asked through his work.

I appreciated everyone's help and got some great info, but still the question remains about the video. Maybe I will try asking the guy who posted it or rolling the die and see what happens

I would not panic... There will always be tubes around as the more and more machines get lcd's put in them.. Shit i am still even throwing tubes in the bin if they get in the way..

Universal in regards to these chassis meant it fits many brands of tubes... you still need to match it as close as you can or it will go bang..

In most cases those chassis will go bang in a few years anyway

I would not panic... There will always be tubes around as the more and more machines get lcd's put in them.. Shit i am still even throwing tubes in the bin if they get in the way..

Universal in regards to these chassis meant it fits many brands of tubes... you still need to match it as close as you can or it will go bang..

In most cases those chassis will go bang in a few years anyway

 

True true 👍👍

Intrigued by this thread, I found this. The chassis looks very similar to yours. Maybe the table for changing the R C values would help.

 

http://www.genao.com/datatech/monitor.html

Intrigued by this thread, I found this. The chassis looks very similar to yours. Maybe the table for changing the R C values would help.

 

http://www.genao.com/datatech/monitor.html

 

Thanks Arcadus for your reply,

It's a angle I hadn't thought of - change chassis to suit tube. I suppose that's want the guys do when they make up chassis to suit crts. I had a good look at the table in that link but unfortunately the chassis I have is different and to hard for me to work out what parts would need to be changed as they are different, see attached pick of cap 412 - on table it's a large cap on mine it's a small blue ceramic cap.

Also attached is just a couple of photos of the chassis.

Just for interest, the vertical deflection yoke (V.D.Y) is located centre right. R321, and the unnamed capacitor and resistor to the left would have to be adjusted. I have no idea how to calculate this, need an electronic engineer. There is a unpopulated spot on your chassis with a cap and resistor symbol near the yoke connection. Anyway this is a result of idle net surfing...Please ignore at will.

Thanks Arcadus,

I think u r onto some thing here, I also would need help from someone like a electronic engineer to work it out, the other option and more my style would be to buy a Wei ya low impedance chassis and copy the difference, I have x2 of the same TV tubes that I'm trying to use so by hunting down a similar chassis but low impedance may be the go as I can use that one and change the other one to get me x2 usable chassis. I'll have a look at what I can find.

 

 

Sent from my iPhone using Aussie Arcade

Don't assume componant vales will be the same between different brands.

 

Every part is usually different and different FBTs will have different requirements for the yoke that they drive.

 

It is all a very delicate balance.