CurtPalme.com Home Theater Forum

KrisRoberts · Joined: 21 Jan 2007 Posts: 115 Location: San Diego

I purchased a new P19LUG for my G90 from Tubular Outlet. Terry put on the mounting hardware and I installed it. Actually they sent him one tube first that had silicon residue and a couple nicks on the glass face of the tube. It seemed a little questionable as to whether it was 'new' - but they were good about promptly sending a replacement for that first one.

When I received the tube I followed the excellent instructions from John HWMan for removing the old one and replacing it with the new one. I had taken the green tube out to fill up the glycol when I first had it, so I was generally familiar with the process. Having the new tube already setup with the mounting hardware and everything made it a breeze. Everything seemed to go smoothly.

With the new tube in the projector and everything put back together I fired it up. With the same settings for EM focus and registration, it was off but not as bad as I would have thought for being a completely different tube and swapping the coils and everything by hand.

I noticed however that there were some blemishes. I tried to take some photos of them with that rough setup here:
http://www.vidya.com/kris/G90

They appeared to be little spots that focused very sharply with the scan lines. At first I was optimistic that they were bubbles or residue, but after doing more detailed setup they didn't go away and looking closely at the tube face they appeared to be on the phosphor side of the glass rather than in the glycol side. They were not really visible with the tube off unless I had a flashlight pointed at just the right angle to get them to glisten - to my eye they looked like slight imperfections in the glass.

The folks at Tubular instructed me to send it back to them with the mounting hardware still attached so they could take a look at it. After having it for a week I heard from them today, and their position is that they are spot burns. They say there are actually two sets very close to each other, one that has burned all the way through the phosphor and one that is not quite all the way through. I believe those are the companion spots I see in the screen shots above.

Nothing bad seemed to happen when the projector was turned back on after the tube swap. No drama or anything unusual. The tube I had before never got any burns. The red and blue have no burns. Returning the old tube back into the projector has had it running fine with no spots showing up.

The Tubular position is that they do not warranty the tubes against burns, so I am simply out a green tube. They are confident that it was burn free when it left their facility. But they don't have any real idea what would cause two sets of similar burns. Its not the normal collapsed deflection burn, or anything I've seen photos of.

Has anyone seen this kind of spot burn before? Any theories on what could cause it?

jkruger · Joined: 24 Oct 2007 Posts: 2435 Location: Carlsbad, CA

Kris, I looked at the pics and the stuff on other site too and I'm guessing it's a bad phosphor coating job from VDC. I'm no expert on the subject but that's what it looks like to me. By the way, thanks for having me over about a year ago to see the G90 in action... I have since moved up to a 9"LC Runco and am loving every day I spend with it. Very Happy

David_Web · Joined: 02 May 2007 Posts: 418 Location: Sweden

It looks like the CRT equivalent to a dead pixel.

A red M8000 tube I have has it as well.

If it where spot burns would they not have some sort of trail leading to them?
I don't think you could even make them if you wanted to unless you feed the scan yokes a steady DC and then zap the tube with an electron stream.

It's ether a mfgr defect or some sort of cathode contamination getting hurdled at the phosphor at high speed.

At least that's my theory.

Chuchuf · Joined: 11 Mar 2006 Posts: 548

I don't know Kris. I have changed and seen hundreds of tubes and never seen anything like this unless it was a defect in the tube. The more I think about it I'm not sure how you could burn two spots that small in the face of the tube?
My experience w/ Tubular Outlet is running about 50% on 9" tubes I have purchased from them. The obvious used tube of yours they sent as new that I had to return, the time they sent me a P19LBP03 when it was supposed to be a P19LUG. I don't know, my confidence in them is not high at the moment.
There may be something else to consider here. I don't believe that these tubes are made at MEC as they used to be. I think they are made in China by someone else who (perhaps) purchased the mfg line from MEC.
When I received the tube from them to mount for you I looked at the face, but obviously not close enough to catch the problem. I don't recall seeing any defects but then again, the tube looked new so I wouldn't have gone over it with a fine tooth comb. And I suspect that it would take a magnifying glass to see that defect on the face. I never fired the tube up so I wouldn't have seen what you did.
Normally when the beam colapses you het a vertical line pattern through the center of the tube. I both the H & V colapse I suppose you could get a dot but not that small. I think this is phosphor defects.

Terry

garyfritz · Joined: 08 Apr 2006 Posts: 12088 Location: Fort Collins, CO

That's what I thought too. You don't get spot burns in multiple random spots on the tube face. Those are phosphor defects and they should replace your tube.

ecrabb · Posted: Wed Oct 29, 2008 5:13 pm Post subject:

That's what I was going to say last night, but I was falling asleep and couldn't form a cohesive thought...

If you get spot burn, it's always near the center of the tube because you don't have deflection. If it wasn't in the center of the tube and something went whacky, you wouldn't get a nice pin spot, because you'd have deflection. It's a one or the other situation. You simply can't get one or two nice dots way off center.

With the lenses off and a magnifying glass, you should be able to see that it is indeed a phosphor defect. It's entirely possible that it was fine when tubular packed it up and shipped it out, then the coating literally fell off in transport or handling.

Regardless, I think they owe you a replacement.

SC

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Yeah thats not spot burn or even a deflection yoke short burn like this one:

https://www.curtpalme.com/forum_archived/viewtopic.php@t=11051.html

I say its some contamination form a badly rebuilt tube if it is rebuilt. If you paid with a CC i'd call the credit card company and ask for a charge back. tell them you tried to
resolve it and the company wont.

Athanasios

kschmit2 · Posted: Wed Oct 29, 2008 8:31 pm Post subject:

I also had that on 2 new NEC PG tubes a couple of years ago. Phosphor impurities, or uneven coating.
Doesn't matter what, it's a manufacturing defect.
It was no problem to get them exchanged back then, but back then we were dealing directly with the manufacturer or distributor of the tubes.

KrisRoberts · Joined: 21 Jan 2007 Posts: 115 Location: San Diego

Tubular insists they are 'burns' and were not present when they shipped the tube.
They must have been caused by my equipment/installation and burns are not covered by their warrantee.
End of story from their side, the business person will not respond to requests to call me for any discussion.

Seems suspect to me.
The first tube they sent me had obvious issues and didn't appear to be new. Strike one for their quality control.
The second tube looks good to the naked eye, but showed the blemishes on the screen from the first time it was turned on.
The label on the second tube also does not match the image on the ebay auction - it does not say Panasonic anywhere on it.
The only person who I have spoken to from Tubular is a tech who admits he has not seen burns like this before and has no theory as to how they could be created by my projector.
My projector never burned the original tube, and returning the old one to the projector has continued to run fine since.

Does anyone have suggestions on where I could have the tube sent for a professional second opinion?
It seems like negative ebay feedback may be one of my only options.

ecrabb · Posted: Thu Oct 30, 2008 11:21 am Post subject:

Terry IS your expert. If his expert opinion is that it was defective, and you have a series of other experienced individuals all of the opinion this isn't spot burn and that the tube is defective, I don't know what else anybody else could possibly say.

If they won't talk to you any further, I'd start the credit card chargeback immediately.

SC

jkruger · Joined: 24 Oct 2007 Posts: 2435 Location: Carlsbad, CA

Kris, Can you post a link to the ebay ad?

KrisRoberts · Joined: 21 Jan 2007 Posts: 115 Location: San Diego

Their standing auction for P19LUG tubes is item number 260201012369 on ebay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWAX:IT&item=260201012369

Seems pretty clear that the tubes being offered are supposed to be new Panasonic tubes.
First one had been mounted before, unclear if it was ever 'used', but had knicks on the glass face of the tube.
Second tube was not labeled as Panasonic.
After installation showed spot blemishes on the first powerup.

ecrabb · Posted: Thu Oct 30, 2008 4:44 pm Post subject:

Hmm... The auction states:

**Curt Palme** · Posted: Thu Oct 30, 2008 4:44 pm Post subject:

The last tube I got from Tubular Outlet (about 6 weeks ago) was NIB, but did not have a Panasonic sticker on it, it was some other Chinese (?) company that I'd never heard of before. I will be firing it up next week.

Speculating only here, I'm assuming this new company did indeed buy the Panasonic production line, as last time I talked to Charlie at VDC, he said that VDC did not buy the production line since they already had one in place.

I'll post once I fire this tube up. I had two warranty tubes, P19LUG that didn't focus properly, these did not have phosphor flaws. Both of the tubes I had go bad simply wouldn't focus properly, massive flare/haloing around the dots at high contrast. The second tube acted up after 100 hours of use, the first one I rejected right away. THe other 2-3 tubes I've bought from them have been fine.

Z-Photo · Posted: Thu Oct 30, 2008 4:59 pm Post subject:

So I have been out for a while -

Why shop at Tubular outlet in the first place - can you not get the panasonic tubes from VDC?

900+ for a 8" tube seems a tab (extremely) high to me - especially if they are selling crap.

**Curt Palme** · Posted: Thu Oct 30, 2008 5:03 pm Post subject:

No, it's $900 for a brand new 9" tube. VDC wants $1650 for the same thing... up to now..

CRT_Ben · Joined: 28 Aug 2006 Posts: 1684 Location: Northern Virginia

So it sounds like the collective experience here (Curt, Terry, Kris) is about 50% with "brand new" tubes. That's not very good... Confused

File a chargeback for sure.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I hope those new Thomas tubes with sony pin outs for 100 each are ok when i get them Very Happy

Nashou

PS rubbing it in Wink

Z-Photo · Posted: Thu Oct 30, 2008 6:15 pm Post subject:

Curt what i see on the web is $985 for a "new" P16

http://www.tubularoutlet.com/NewP16LXV.htm

and 180Dyb tubes

http://www.tubularoutlet.com/New180DYB.html

HaydnG90 · Joined: 22 May 2006 Posts: 1356

Best course of action is to contact your CC and initiate a callback. There is clearly a defect that doesn't appear to be the result of spot burn. The CC will almost certainly take your side as at the moment its a he said-she said situation. Confirmation that this is not spot burn from one or two well respected CRT experts will bolster your case.
I love this bit in their warranty/return policy "Your satisfaction is our best advertisement."
They are certainly not winning many friends on this site or AVS, where undoubtedly much of their business originates.