Toshiba 27" CRT TV (27A33, 2003) bowed in at sides
 

My set has a pincushion issue where it bows in at each side, horizontally. There is no option in the service menu to fix this. I've owned three of this model and they've all had this issue. What could be causing this? Could it be as simple as some faulty capacitors in the vertical deflection circuit? The picture is excellent otherwise and my TV only has 6,000 hours on it according to the service menu.

I have a similar set, the 27A32. My guess is the same TV but a year older. I haven't noticed the problem you are having but did have several caps go bad in the power supply. At first it would power up then turn off, Turn on again and it was okay. Then it took a couple of times, Then it took many times. I replaced a bunch of electrolytic caps in the power supply and it has been fine every since. I think when I checked several years ago the set had something like 18,000 hours on it. I still watch it a little when I go to bed.
EDIT: Boy was I off! It has 31,826 hours in 2000. Now it has 32,767! I guess that seems about right.. about a half hour a day.

Do you have an ESR meter? I wish I would have had one when I repaired mine. I made a list of all the electrolytics in the power supply and replaced them all. Back then, I only had a component tester that would test out of circuit. So, if I removed it, it got replaced. It wasn't a lost cause though, many were high ESR.

Here is the post at AudioKarma that I made about this 5 years ago!
https://audiokarma.org/forums/index..../post-13398066

I wonder if the adjustment you are looking for is called parabola? Be careful if you start screwing around with this stuff. You might end up way worse!

https://www.reddit.com/r/crtgaming/c...perations_for/

I adjusted the parabola service menu item and it didn't fix anything. Parabola adjusts corner pincushion but doesn't do anything to fix bowing in at the sides (looks like an hour glass).

There's a few possiblities that would have the effect you are seeing.

You already eliminated the easiest one, which is bad adjustment.

That leaves dead components. The by far most likely thing is one or more electrolytics have failed. As you heard from redk in their previous post.

The function that controls the parabola is called "EastWest" and is probably denoted in the schematic for your TV as the "EW out" pin on the monolithic video IC. This can be seen at pin 59 on page 22. It joins the deflection circuitry at Q411 on page 23 (towards the upper left side of the page).

I would focus on the electrolytics in this section, beneath the vertical output IC.

However, I would also heed redk's advice and check the electrolytics in the power supply, and I would also check all of them in anything that gets hot (next to a heat sink or power resistor) or just any of them in the deflection area as those tend to get a lot of juice.

This set is an Orion set (not actually made by Toshiba) and it's 2003, which is capacitor plague era. There's every possibility that all the lytics are going to leak or explode unfortunately.

I will probably just wind up replacing the capacitors in those areas. There aren't that many. I do notice that the vertical deflection section of the board is a darker brown than the other parts. This TV has a beautiful picture. The tube has a an Orion sticker but it was actually manufactured by Matsushita. 6th gen games look especially amazing on this CRT.

If that's the case, then you very well might have some cold solder joints in that area on the board. That would actually make even more sense than just bad caps, as bad caps are usually enough to have at least some effect. Total loss of pincushion sounds like a broken connection.

Go over any place on the PCB that looks "dark" or different very carefully with new solder and make sure it's all reflowed.

Also reflow anything that is big and heavy (like the flyback and big resistors) or connectors (because they get stressed).

It's also likely that the caps need to be checked though.


Andy and Matt's database claim that it is fully an Orion set that was rebranded with a Toshiba badge. But you don't have to take my word for it.

Thanks for the help. I will likely be doing what you suggested. As far as I can tell, it is incorrect that Orion made the tube in the 27A33. Orion did manufacture the circuit boards and TV casing but for the Toshiba 27A33 model but as far as I can tell, they did not manufacture the tube. It was a common practice for Orion to use tubes in their Orion branded CRTs that were manufactured by other companies and in this case, Matsushita (AKA-Panasonic) was the company that manufactured the tube. Like you, I originally thought that Orion manufactured the tube but after having discussions with knowledgeable people on the CRTgaming subreddit and the CRT Collective on Facebook, it seems that this isn't the case.

I also have a Panasonic 27" CRT TV (model CT27D11E, made in 2001) and the tube in that set has the same codes on the label as the Toshiba 27A33. The codes on both tubes are E118951 and LR29056. Another similarity between the tubes is that both tubes have a bold "M" at the top of the label with a square around it. This is the symbol that Matsushita used on their tubes to indicate that they manufactured the tube. This is the symbol I'm referring to, https://deskthority.net/wiki/File:Br...(IE139097).svg. Another piece of information comes from the Union Electronic Distributors website. They have been one of the largest suppliers of consumer electronics parts since the 1950s. The following link shows the tube in the 27A33 (tube # M68LWF088X50) as being manufactured by PANASONIC (MATSUSHITA), (https://www.ued.net/ued/viewItemActi...68LWF088X50Y5P). The picture also looks very similar on each set. I made a post on the CRTgaming subreddit asking about this, http://(https://www.reddit.com/r/crt...icture_tubes/).

So, I am not saying that I know for sure here one way or the other, but none of those observations are a "smoking gun" for the actual manufacturer of the tube.

In fact, by the time this TV was made, Panasonic had long since already started to farm out the manufacturing of their own devices to Taiwan, Singapore and other places in the Far East.

It is entirely possible and would not be weird that the tube is the same tube used by Panasonic in their own sets AND also made by Orion, specifically for Panasonic (thus the "M").

Maybe. One thing that is odd is the tube in my Toshiba 27A33 having the Matsushita logo on the label. When considering the theory that it was a tube made by Orion for Panasonic, wouldn't the label have a Toshiba logo on it because it would be a tube made by Orion for Toshiba? If Panasonic tubes really were made in an Orion factory, did Orion or Panasonic design the tube? If Panasonic designed a tube that was built in an Orion factory, I would still say it's a Panasonic tube because Orion didn't design it. I will note that the tube in my Panasonic CT27D11E was made in the U.S. I'm not sure if Orion had CRT factories in the U.S. Do you have any official sources that mention when Panasonic outsourced production of their CRTs? Based on what I've seen, the Orion that worked with Panasonic did not make their own picture tubes. My guess is that Panasonic built their own factories overseas because it was cheaper than making CRTs in Japan and allowed Orion to put their label on the tube because they designed the other parts of the TV. I used to own a Panasonic Superflat (GAOO) set from 1999. The tube in that set was made in Japan by Matsushita so they were still making (at least some of) their own tubes very close to the date that my CT27D11DE was manufactured. I could be wrong but that is just my opinion. It doesn't really matter I guess. I just want people to know that the Toshiba A series CRTs like the 27A33 still have an excellent picture, in spite of having Orion branded tubes.

Does the tube have an EIA number? That would identify the manufacturer.

I took pictures of the tube labels before. The EIA number on the Panasonic set is EIA130. In my picture, I don't see an EIA # on the label on my Toshiba 27A33.