List of compatible tubes?

[uncletom]

Ah.. no. 110 degrees you mean. 90 are the smaller CRT, like 19-25 inch. I have never seen a 90 degree 29''. The CRT is often branded, actually relieved text in the main glass bubble that specifies like "110".

And yes, you measure the heater voltage. DC between pin 9 and 10 in this case.

[Wurstkopp]

Ah, I thought the 110 on the back meant the voltage, ok, its the angle. How do you find out about the a,b or c-class tube? I have a III on a spare tube here, does that mean its a c-class tube?

[dieKatze88]

Katze you're just looking in the wrong places. Alva amusements sells that chassis domestically for 180 usd. Not bad right?

Not bad. I might consider that, I've got one of thoes 45 dollar weiya video upscalers, and I don't really care about the 15khz picture if I can upscale it to 31khz with no lag...

[uncletom]

How you know that it's a A, B or C grade tube? Easy. You will know once you see the picture. Then you must decide if you want to keep it.

Typical problems with 'not TV-speced' CRTs are poor convergence, uncurable coloring/magnetizing puity problems, phosphor damages of various sorts, and any other blemishes done by accident in the factory to the material. I thought there were only A and B grades, the C must look really aweful I can imagine.

Also, because the CRT often comes with the yoke attached/glued, any problems caused by a faulty installation of yoke are also considered in the grading of the CRT.

[uncletom]

Hm... "Ah, I thought the 110 on the back meant the voltage" - you don't understand. I meant the reliefed big text on the glass bubble, which is then painted with the conductive paint. Not the 110/220 Volts specifications. In such case ofcourse the lable mentions "Volt AC" or something. Please don't confuse the CRT-degrees with input voltage.

Then again not all CRT have text molded into the glass. I've only seen this on several CRTs. Many CRTs have only smooth glass all around. No text. But still, you can see if it's 100 or 90. Look from profile, compare like a 20" with a 29" CRT you will see the shape difference from both front and side.

[Wurstkopp]

Hm... "Ah, I thought the 110 on the back meant the voltage" - you don't understand. I meant the reliefed big text on the glass bubble, which is then painted with the conductive paint.

I know what you meant. The reliefed text says "29 - 110", so it's a 29 inch tube with an 110 degrees angle. Also there's a big "III" (3) below that. The tube comes from a very expensive broadcast monitor.

[uncletom]

Right.. yes. That should be it. But not all CRTs have this text, so one must rely on the shape of CRT itself. It isn't very hard to spot.

Also, for information on many CRT for which you have no previous neckboard, I use this info. And there you can also see what heater voltages and socket type are used:

http://hornet.homeftp.net/CRT_socket_ty ... oltage.pdf"
http://hornet.homeftp.net/CRT_socket_type.pdf"

Also, I can confirm that our 29" Toshiba for MS9 (A68KJU96X) has heater voltage 6,3V.

Important also is, that the socket references in these documents are not of any general standard, but only standard for the specific application used in the documents. For instance; "A8" in one document and "23" in the other document means the same. You will need to refer to the socket pinout as K=6,8,11 for short, and specify heater voltage.

[Wurstkopp]

Thanks for that list, dude!

According to the list the Toshiba A68KLF96X02 has the same heater voltage (6,3) and the same socket type (23). Anyhow, I will check if its correct and give the yoke swap a try then...

[uncletom]

That sounds like an interesting project. I think that you will be very successfull.

Now, yesterday evening I measured the yoke of my MS9 (Star Wars Trilogy Upright) and I was amazed that the coils were 7 Ohms, and 0,7 Ohms about. This is very unusualy I think. So please, never trash a yoke. Particularly from a Nanao MS9 monitor.

The MS8 has more of normal values, I think last time I checked it was 30 something.. Ohms and 1,5 Ohms. So "high impedance" yokes, less rare, could be used for MS8.

Also here, important during monitor operation the first time testing is your smell. Always notice any strange smells and be ready to Switch off quickly.

[Wurstkopp]

Why not get a TV tube and do a yoke swap.
All you need is to decode the tube reference number for curvature etc and nuber of pins on the neck and swap them over....
I did one a few years ago and while not perfect it was acceptable.

I'm currently checking for TVs in my region to do the swap but all 29" TVs I found had different curvatures (they're mostly semi flat or real flat). It seems there are not that much super curved 29 inch TVs with 60 Hz out there.

What TV did you take if I may ask, Penrhos?

I think a list of super curved 29" TVs with would be great. Here's what I found:

- Toshiba 2929 DD.

[uncletom]

Well, all 29'' I've seen are semi-flat. After 26'' they just get flatter and flatter it seems. The largest 'round' tubes I've seen are 27''.

Those pure flat CRTs you cannot use. They require some different chassis, often using two focus-pots.

And always save the old neck-board for reference to what pinout the CRT has.

[Wurstkopp]

There are a few, the Tosh 2929DD actually has a rounded 29" tube. There are also two american TVs, a Samsung and a Hitachi TV, if I remember correctly. They also have rounded 29" tubes. But there have to be more out there..!

[emphatic]

It seems there are not that much super curved 29 inch TVs with 60 Hz out there.

Do you really have to account for PAL/NTSC compatibility when you just need the tube? Isn't that managed by the chassis?

[dieKatze88]

It seems there are not that much super curved 29 inch TVs with 60 Hz out there.

Do you really have to account for PAL/NTSC compatibility when you just need the tube? Isn't that managed by the chassis?

I would imagine so. Especially considering later TVs in all regions started supporting both NTSC and PAL, My 29 inch RCA television supports PAL (I know this for fact! I put a pal signal in and got a lousy picture out of it. PAL = Picture Always Lousy. Perfect!) and many of you guys across the pond have TVs capable of receiving a NTSC signal and "Just dealing with it"

[uncletom]

Ok, first, the CRT has nothing to do with PAL och NTSC standards. They are on a completely different level of technology than a simple CRT.

To best describe the CRT, it is the component that the picture is projected on (or rather from within). It is like the canvas in the cinema, a white wall. Think of the CRT as the 'wall' in which the picture is projected, nothing more. Ofcourse the dot-pitch can vary between different CRTs, and the yoke controlling the beam can also vary, but otherwise all CRTs work the same way.

What you should regard is: neck pinout, heater voltage and geometry (form of CRT body/bulb).

This is, I assume, that we are talking about 29" CRTs. Otherwise also high-voltage must be regarded when using smaller CRTs. Usually what I heard is that a 1000 Volts per inch. So 29" uses 29kV, and 14" uses 14kV. Something like that, but I'm not sure how this rule applies in reality as I have never yet needed to measure the high voltage.

[penrhos]

I used the tube from a Panasonic or Toshiba TV.

[cools]

I've bookmarked a few websites for tube/yoke swaps that provide good info..

http://www.ionpool.net/arcade/tubeswap/tubeswap.html"

http://www.8liners.com/datatech/monitor.html"

http://arcadecontrols.com/files/Miscell ... crtfaq.htm"

http://www.coinop.org/repair/Monitor_Tubeswap.aspx"

http://www.arcaderestoration.com/"

Anyone got the tube reference decoding key?

I know A68 = 68 cm = 29" A63 = 63 cm = 25" - I know some of the other numbers describe the pin layouts & heater voltages.

Sad, 15 years later only 2 links still working

[uncletom]

It seems so. That's evolution for you.

[arcnl]

Wayback machine has two of the nonworking ones at least

https://web.archive.org/web/20190926012 ... eswap.html
https://web.archive.org/web/20070320203 ... nitor.html

One of those original urls is blocked on my corporate computer for some reason

[uncletom]

Is there any use for a CRT today, other than for our hobby? Is there any purpose for a CRT in modern industry, or even military? Because I've not found a single CRT in my recycling for the past 10 - 15 years. So CRTs in consumer displays are dead and gone.

So be gentle with the ones we still have.