CurtPalme.com Home Theater Forum

[daves123]

Is the green tube in a NEC XG 135LC the same as the green tube in all XG models, and PG XTRAS? Or do the LC units use different tubes?

[macgyver655]

Here's a good chart to answer those questions.

http://www.curtpalme.com/PJSpecs_NEC.shtm

[daves123]

Yeah, i've looked at that chart. I've also read that the green tubes (and only the green) from the PG XTRAS are interchangeable with the XG models, but when I look at the chart, the xtras are listed as P16JLE, and the XGs are listed as P16LJE06 or
P16LJE07 or
P16LJE08

[macgyver655]

That is a misprint in the chart. The PG Extra tube is also a P16LJE.

[daves123]

The chart says that the xtra tube is a P16LJE, so i'm a little confused. Are the green tubes infact the same?

[macgyver655]

Yes, the green tubes are the same.

[daves123]

Thank you. Some of the info out there seemed contradicting and just wanted to clear it up.

[Mark_A_W]

No they are not the same.

The 06 and 07 model tubes, fitted to an XG, have an Extra KH grid.


To run an 08 tube in my XG I removed the KH resistor from the neckboard (the one from the KH pin to ground). I'm not certain if this was required, others haven't done this.


Also, the LC and AC housing are completely different. They can be swapped, but it is an ENORMOUS amount of very delicate work.

[macgyver655]

Mark. The PG Extra green tube is a P16LJE08. The XG's also use the P16LJE08. You yourself have also said that these tubes have been swapped without modification.

[Mark_A_W]

[macgyver655]

[Mark_A_W]

Ok, if you read it, you'll see I am unsure.


If you do it without removing the resistor, you are grounding G1, through a 3M3 resistor. Not sure if that is a good idea or not.

[macgyver655]

So I guess your final answer is your not sure. Lets see if we can find an answer with some facts. These facts are from NEC service manuals.

First lets see what tubes are used in what machines. All facts pertain to the green only for this issue.

6/9 PG EXTRA....P16LJE08HKA
XG750,1100,1350......P16LJE07HKA
XG751......P16LJE07HKA
XG1101,1351(LC's)......P16LJE06HKA
XG852.......P16LJE07HKA
XG1352(LC)....P16LJE06HKA

As you can see the PG Xtra uses an 08, XG non LC's use 07 and XG LC's use an 06.

So now lets look at the neck boards to see whats up. Pics will be attached below showing what projector the schematic is for. First, if we look at the PG Xtra schematic we see the (2) G1's are tied together, have a spark gap and then you can see the incoming G1 line.

Next we look at the 750,1100,1350 schematic. Huh, same design for the G1. Both tied together, spark gap and incoming line. But wait, thats an 07 tube. Same as the 08 tube. Guess that should be a swap no problem. Hmmm, but the 07 was also used in the 751 which the neck board has a different design with 2 amps and (1) G1 line through a resistor going to ground. So I guess the 07 tube will work with either type of G1 system design. So the 08 also works in the 1 amp neck board so it should also work in the 2 amp board.

Now the 751, 1101 and 1351 all use the same neckboard but the 1101 and 1351 use the 06 tube. So these tubes will swap no problem. Then we have the 852 and 1352 which is the same neckboard as the 751,1101,1351.

So when we put all this together, all these tubes should swap without any issues. I'll leave it at that unless any comments require further discussion.

Here are the diagrams:

[Mark_A_W]

There are three problems with what you just wrote...

1. The service manual is wrong in that area, it does not match reality.

2. Both LC and AC projectors had either 07 or 06 tubes, they even mixed and matched in the same projector. It doesn't matter as they are identical. My XG-751 came with 06's, contradicting your list. But it shows how useless "facts" from a NEC manual are.

3. Some XG's (at least in the US) were fitted with 08 tubes from factory. They came with a sticker saying to retube only with 08's. To me this may imply a different neckboard, or just a different white balance required, without seeing one, I cannot say. This is why I am unsure.


I do not trust those schematics as far as I can throw them. I know the XG version 1 schematic is wrong.


I don't have the version 2 service manual (852/1352). Is there any way you can upload that so I can download it?

[macgyver655]

[Mark_A_W]

All the first two XG manuals are wrong in the PIN area, I think. Certainly the xxx1 XG manual is wrong.

I don't have a loose neckboard to compare offhand, Mike P has them, but I should get some in the next few weeks. What's wrong is the KH grid details. Have you got an XG neckboard handy?


I haven't seen an XG factory setup for 08's, but Doug has. I trust Doug.


And the tube numbers are still wrong. Like I said, my XG came with 06's, including GREEN.

I will PM you my address (but it's a hundred mb isn't it?).

[macgyver655]

[Mark_A_W]

?Doug said the tubes won't swap?

I was not so sure, and then compared the real neckboards between the XG and Xtra, and I modded mine so the neckboard didn't have the (unused) KH connection with the 08 tube. I did this 4 years ago, so the exact details escape me.

I know of an XG-xxx0 running an 08 without mods, but no xxx2/xxx3 XGs. I also think that the G1 is grounded through that resistor,may be ok, may not be.

And no, I didn't buy it new, but it had not been retubed. It's easy to tell a retubed projector, the red glue (like nail polish) on the focus coils must be broken to change a tube.

[macgyver655]

What version is your XG?

[Mark_A_W]

It was a 751, now it is a 1101LC (sans extra fan and correct sticker).