AVS › AVS Forum › Display Devices › CRT Projectors › New green p19lug for barco 1209
New Posts  All Forums:Forum Nav:

New green p19lug for barco 1209

post #1 of 22
3/31/09 at 12:11am
Thread Starter 
I just finished installing a new blue and green tube in my Barco 1209. For the green tube, I decided to go with a p19lug tube from greg eisemann who also made the neccessary modifcation to the neck board for me. For those who are on the fence about making the lug upgrade and having trouble finding much info and any realized improvements, I highly recommend that you do. There is a significant increase in the sharpness of the picture. It's amazing how good this old crt technology can still be. My system include dtv, ps3, hd-a3, lumagen hdp processor, and Barco 1209 with eisemann mods and green p19lug.

ltv
Reply
Reply

AVS Top Picks

post #2 of 22
3/31/09 at 7:26am
Was the "mod" you did to use grid3 on pin 7??

Terry
Reply
Reply
post #3 of 22
3/31/09 at 9:24am
Terry, I don't know what the mod is but Greg says he mods the neck cards of the 1209s for use with LUGs

-Gary
Reply
Reply
post #4 of 22
3/31/09 at 4:50pm
Thread Starter 
Terry,

I don't know what was modded on the neckboard - maybe greg can comment. I've gotten very comfortable with installing and setup but definitely do not have the know-how to be modifying boards.

BTW: your blue tube installed without problems and is working fine. thanks.

Loi
Reply
Reply
post #5 of 22
4/1/09 at 6:51am
Great Loi,

Ah these are Gregs mods. The reason I asked is the only difference between the LUG pinout and "stock tube" pinout is the addition of "grid 3" or KH grid on pin 7.

Glad to hear that B tube worked for you.

Terry
Reply
Reply
post #6 of 22
4/1/09 at 10:42am
so what exactly is Gregs LUG mod for 1209s neck cards?

-Gary
Reply
Reply
post #7 of 22
4/1/09 at 11:54am
Quote:
Originally Posted by Gary Murrell View Post

so what exactly is Gregs LUG mod for 1209s neck cards?

-Gary

I forget the pins but that additional grid I believe needs to be grounded out. Barco did a straight connection is what I have been told, but the recommended way is to use a 1 megaohm (I think) resistor to avoid noise. I pretty sure this has been discussed here before.
Reply
Reply
post #8 of 22
4/1/09 at 4:25pm
so what do you gain?

-Gary
Reply
Reply
post #9 of 22
4/1/09 at 5:17pm
Quote:
Originally Posted by Gary Murrell View Post

so what do you gain?

-Gary

The Barco 1209s doesn't use the extra grid so it needs to be grounded out otherwise you have operational issues (I think the G2 goes high). The way the pin is ground in a stock 1209s could induce noise or at least that is what I have read. Using a resistor potentially reduces the noise. So you may gain nothing over stock. At least that is what I have read/been told. I am not an expert.
Reply
Reply
post #10 of 22
4/1/09 at 7:37pm
Quote:
Originally Posted by secstate View Post

I forget the pins but that additional grid I believe needs to be grounded out. Barco did a straight connection is what I have been told, but the recommended way is to use a 1 megaohm (I think) resistor to avoid noise. I pretty sure this has been discussed here before.

One of the original tube pinout diagrams had a comment at the bottom of the sheet:

"Note: (1) resistor of over 1 M ohm and 1/2 watt installed for KH pin (No. 7 pin) in order to get low capacitance efficiency."

http://www.avsforum.com/avs-vb/showt...6#post14440796

Ray
Reply
Reply
post #11 of 22
4/1/09 at 9:19pm
Quote:
Originally Posted by secstate View Post

The Barco 1209s doesn't use the extra grid so it needs to be grounded out otherwise you have operational issues (I think the G2 goes high). The way the pin is ground in a stock 1209s could induce noise or at least that is what I have read. Using a resistor potentially reduces the noise. So you may gain nothing over stock. At least that is what I have read/been told. I am not an expert.

on Gregs site it says you get a blurrier focus without the mod

-Gary
Reply
Reply
post #12 of 22
4/2/09 at 10:38am
I sold Loi a high rez simulation grade Boeing tube and modified the neck card.

These are the best tubes from my testing and seem to be much better than the the panasonic tubes. Especially on corner focus.

Some years back I did research and testing modifying neck cards. I find the resistor or directly combining the KG grid to ground caused more noise in the picture and tends to blur the detail slightly. Its better than leaving it open, leaving it open gives you a wide beam that is very poor focus.

I then experimented not using ground as its a source of chassis noise and a general antenna for interference. I then combined the KG grid to the other grid in the tube directly without going to ground at all. This provided the best result in focus and much lower noise.

This was the ticket and have been doing it ever since the first tests.

On the 1209 you just add a wire.

On 1209s I had to cut round the pin to isolate the pin from ground with a dremmel and then tie the grids tougher.

I will have to post a schematic later when I get home.

PS.. my email mailbox was overloaded so I upgraded to a new one for anyone who got a email bounced back...

PSS... my new HDMI card is now shipping for barco.

Greg
Reply
Reply
post #13 of 22
4/2/09 at 3:38pm
thanks Greg

-Gary
Reply
Reply
post #14 of 22
4/3/09 at 7:44am
Quote:
Originally Posted by geisemann View Post

I sold Loi a high rez simulation grade Boeing tube and modified the neck card.

These are the best tubes from my testing and seem to be much better than the the panasonic tubes. Especially on corner focus.

Some years back I did research and testing modifying neck cards. I find the resistor or directly combining the KG grid to ground caused more noise in the picture and tends to blur the detail slightly. Its better than leaving it open, leaving it open gives you a wide beam that is very poor focus.

I then experimented not using ground as its a source of chassis noise and a general antenna for interference. I then combined the KG grid to the other grid in the tube directly without going to ground at all. This provided the best result in focus and much lower noise.

This was the ticket and have been doing it ever since the first tests.

On the 1209 you just add a wire.

On 1209s I had to cut round the pin to isolate the pin from ground with a dremmel and then tie the grids tougher.

I will have to post a schematic later when I get home.

PS.. my email mailbox was overloaded so I upgraded to a new one for anyone who got a email bounced back...

PSS... my new HDMI card is now shipping for barco.

Greg

Which Grid are you attaching the KH grid 3 to?? Grid 1 or Grid 2??

Thanks,

Terry
Reply
Reply
post #15 of 22
4/3/09 at 8:36am
I have been doing it from memory.

Its the KG skip a pin then connect to the next pin

Pin 7 is KG
Pin 6 you skip
Pin 5 you connect to KG

So connect KG pin 7 to G1 pin 5

From my testing it works much better than the resistor.

I find the resistor or the ground it self added noise? IT worked ok but the 1080p detail was not pefect. By combining the grids the picture achieved a perfect focus with reduced noise. Basically I looked at the gun design and you see the extra KG is a part of the gun G1 on the older tubes so it makes sense to combine. The aperture size and the heater is superior in the LUG.

This extra KG can add control in some simulation applications ie the 909 has a special circuit for KG. The 909 neck cards are designed for PT-22 and P19lug in-fact the projectors had both tubes in them from the factory in some cases.

I hope that helps.

I will try to post a schematic later.........PLEASE ON THE 1209S DON'T FORGET TO DREMMEL THE BOARD AROUND THE KG PIN IF NOT IT WILL BE A MASSIVE SHORT G1 TO GROUND. AFTER YOU DREMMEL USE A DROP OF SILICONE OR HOT GLUE TO PREVENT ARCS
Reply
Reply
post #16 of 22
4/4/09 at 5:27am
Really, G1 to pin 7 (Grid3), very interesting.
Sony attaches a grounded 10M resistor (I think thats the value) to pin 7 on the G90 which uses essentially LUG's.
In looking at the construction of the gun (yup took one out of a tube and inspected it), it appeared to me that the reason for grid 3 was to supress any stray electrons?

Terry
Reply
Reply
post #17 of 22
4/4/09 at 6:08am
Barco 909 uses a 1 meg resistor from pin 7 to ground.

I agree with Terry, it looks to be a Getter Grid.
Reply
Reply
post #18 of 22
4/5/09 at 10:28am
Through some sort of magic this grid lowers the cathode to all other elements capacitance when grounded through a resistor. Perhaps someone fluent in Engrish can translate the exact meaning of the note from the spec sheet.

Scott
LL
Reply
Reply
post #19 of 22
4/7/09 at 12:35pm
The resistor worked fine and I used to do that a few years back.

Just by combining the two pins tougher from my testing provided better results to keep internal cap at the same potential. A resistor or ground seemed to add more noise depending on the state the tube is at cutoff or full on.

The 909 for example has way too much noise to start with, the engineers made a lot of errors and they forgot tricks they learned on the earlier 1209.

( my 909 mod set reduces the noise by adding filters and doing other things to get rid of that terrible shake of the characters)

When the tube was designed they had a perfect environment, something your projector does not have.

The math behind it might be hard to explain here but just from testing I achieved better results not using the resistor.

I have modifyed a lot of 1209s neck cards for customers this way and they said the focus is better. The 1209s ties it directly to GND however

Greg
Reply
Reply
post #20 of 22
4/8/09 at 12:53am
thanks again for the explanation Greg, look forward to seeing all your work in action

-Gary
Reply
Reply
post #21 of 22
4/8/09 at 4:12am
Quote:
Originally Posted by Gary Murrell View Post

thanks again for the explanation Greg, look forward to seeing all your work in action

-Gary


So Gary,you going lug's on all three tubes?


Dave
Reply
Reply
post #22 of 22
4/8/09 at 10:36am
Quote:
Originally Posted by huggy1 View Post

So Gary,you going lug's on all three tubes?


Dave

Yes Dave, Lugs on all 3 tubes

along with Gregs neck card mods, the full mod package from him(entire RGB chain), my internal coaxial cable mod, the red/green c-elements

the works!! I may even try and get a set of 10F lenses to replace the GT17's

-Gary
Reply
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: CRT Projectors

AVS Top Picks

AVS › AVS Forum › Display Devices › CRT Projectors › New green p19lug for barco 1209