| Author |
Message |
tse
Joined: 03 May 2006
Posts: 1014
Location: Sweatbucket, Fl.
|
| Posted: Sun Oct 11, 2009 11:30 pm Post subject: |
|
|
Ok, makes sense that it is the screen. The projector would have to have some major bandwidth to make such narrow lines.
Scott
_________________
"Were we directed from Washington when to sow and when to reap, we would soon want bread."
Thomas Jefferson
|
|
| Back to top |
|
 |
draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
|
| Posted: Mon Oct 12, 2009 2:10 am Post subject: |
|
|
Mike I think I recognize that screen material, it's called painted Burlap 
I've been trying to find a good test pattern to test things with, this is the one-on/one-off pattern from the Calman thing at 1080P. PJ is M8500 with 180DMB tubes and HD8 lenses. Is there a better pattern on this disc? I've looked all through it and couldn't find one.
| Description: |
|
| Filesize: |
35.01 KB |
| Viewed: |
13111 Time(s) |
|
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
| Posted: Mon Oct 12, 2009 5:37 am Post subject: |
|
|
| Nashou66 wrote: | Drags I assume you will have to go into the G2's and adjust there for the proper black level afterwards, Lets wait and see what Mike finds first .
I am still curious if the voltage for the filament changed much from the P14 pin to the point after mikes mods on the VNB? I wonder if lowering the heater voltage would change that brightness issue. if I am not mistaken doesn't that voltage contribute some to how Bright the overall tube will Project. i remember reading somewhere that somebody had the voltage too low and when they raised it to the Proper 6.35 volts the image brightened up? So maybe that cleaner heater supply is like having more voltage to the heater? Hmm Would that then speed up decay of the heater element as if the p14 voltage ran away on you?
Athanasios |
That black elevation thing is something that cannot corrected with G-2. In theory filament should "see" less voltage after this mod. It is RMS voltage that counts, DC+ AC(ac is here that noise voltage) now noise is removed and voltage is actually smaller. With smaller filament voltage tube has lower emission ie dynamic range and maybe we are putting tube away itīs optimum operating range now?
I trye also look this issue little closer if i got time to start my test bench again (it has been in sleep about six months) 
_________________
Marquee 9500LC (Frankenyokes / Thomas electric tubes / HD-10L / +many modīs)
DVDO VP-50
New hobby, Rally
http://www.youtube.com/watch?v=vX2Rtpr1njs
http://www.youtube.com/watch?v=6ZP9FEFXV5c
http://www.youtube.com/watch?v=j065vei6j6s
http://www.facebook.com/pages/JTS-Racing-team/204443719572685
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Oct 12, 2009 10:37 am Post subject: |
|
|
| draganm wrote: | | Mike I think I recognize that screen material, it's called painted Burlap |
LOL..
I finally know what to call my screen material.
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Oct 12, 2009 3:09 pm Post subject: |
|
|
| draganm wrote: | Mike I think I recognize that screen material, it's called painted Burlap
I've been trying to find a good test pattern to test things with, this is the one-on/one-off pattern from the Calman thing at 1080P. PJ is M8500 with 180DMB tubes and HD8 lenses. Is there a better pattern on this disc? I've looked all through it and couldn't find one. |
That's very good for a 8500 with stock tubes and HDF8 lenses. Especially that you're showing the pattern with all three colors on.
For an 8500 or other AC projector, use green only. The better contrast ratio of the LC projectors helps get tighter lines and spacing between the lines when projector on a screen.
I'm not familiar with Calman. The smpte pattern that Use is in DVE (Blu Ray). It's not the cleanest pattern that I've used, but it's the only Blu Ray smpte that I have.
Where can you get a Calman test pattern like the one you're using?
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Oct 12, 2009 3:10 pm Post subject: |
|
|
| tse wrote: | Ok, makes sense that it is the screen. The projector would have to have some major bandwidth to make such narrow lines.
Scott |
I need a better screen..
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Mon Oct 12, 2009 3:30 pm Post subject: |
|
|
| 1031 wrote: | | Nashou66 wrote: | Drags I assume you will have to go into the G2's and adjust there for the proper black level afterwards, Lets wait and see what Mike finds first .
I am still curious if the voltage for the filament changed much from the P14 pin to the point after mikes mods on the VNB? I wonder if lowering the heater voltage would change that brightness issue. if I am not mistaken doesn't that voltage contribute some to how Bright the overall tube will Project. i remember reading somewhere that somebody had the voltage too low and when they raised it to the Proper 6.35 volts the image brightened up? So maybe that cleaner heater supply is like having more voltage to the heater? Hmm Would that then speed up decay of the heater element as if the p14 voltage ran away on you?
Athanasios |
That black elevation thing is something that cannot corrected with G-2. In theory filament should "see" less voltage after this mod. It is RMS voltage that counts, DC+ AC(ac is here that noise voltage) now noise is removed and voltage is actually smaller. With smaller filament voltage tube has lower emission ie dynamic range and maybe we are putting tube away itīs optimum operating range now?
I trye also look this issue little closer if i got time to start my test bench again (it has been in sleep about six months) |
The inductor and caps right on each neck board works very well. It's the size of the inductor and the amount of windings and and wire gauge of the windings is why I'm not measuring a drop in DC voltage at the CRT. I went with a very robust inductor because i knew I would not be able to adjust the 6.3 on my LVPS. It has the fixed mini board.
I've learned something very important going back to this mod. If there's any stray AC noise on any of the PINS on the CRT socket, it WILL effect the overall image.
What I've done by doing this mod was completely cleaned up all the pins on my 9500. I have a G2 mod, but forgot to install it in the projector. It was after I had done the filament mod that I check and found that I did not have the G2 mod done. I then did the G2 mod, and that's when things really jumped to another level.
This is what happens when that noise is not on any of those pins:
- there is an increase in brightness
- there's also a more linear low end
- there's a cloud in the image that's no longer there.
The fix removes snow or cloudiness. And what is seen from the cleanup on a scope, can also be seen in the image when I bypassed the fix with the set on using specific test patterns.
And the changes are very pronounced on the screen when viewing scenes from movies that I'm familiar with. The key is to make sure you dial out the right frequency noise. once done, it can also be seen in screenshots - at least that's the case with my shots.
So overall, there's more clarity and depth in the image. Things also appear to be sharper.
The Marquee folk seems to have made an attempt to clean this up, but nothing that they used seems to be at the right frequency or robust enough.
I'll pick back up on this over on my forum maybe later this week.
|
|
| Back to top |
|
|
Nashou66
Joined: 12 Jan 2007
Posts: 16171
Location: West Seneca NY
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
|
| Back to top |
|
|
Nashou66
Joined: 12 Jan 2007
Posts: 16171
Location: West Seneca NY
|
| Posted: Tue Oct 13, 2009 12:12 pm Post subject: |
|
|
| 1031 wrote: | | Nashou66 wrote: | For the G2 mod what current is the max for this line so we don't put to low current rating inductor in there.
Athanasios |
Current is so minimal there, tube takes only few micro amps . So inductors rating is not critical. |
Just the voltage rating i would matter then, I know that certain G2 value can give more voltage from Tims non scope multimeter test, G2 of 70 is 650 vdc or so.
Athanasios
_________________
Don't blame your underwear for your crooked ass~ unknown Greek philosopher
"Republicans believe every day is the Fourth of July, but the Democrats believe every day is April 15." --- President Reagan
One Smart Dog!!!
Marquee High Performance Bellows now shipping!!
Marquee Modifications and Performance Enhancement
Marquee C-element and Bellow removal
|
|
| Back to top |
|
|
Revox
Joined: 13 Feb 2008
Posts: 158
|
| Posted: Thu Oct 15, 2009 5:35 pm Post subject: |
|
|
Nice mod!
I put an old induktor of an old PC Powersupply infront of the P14 Connector. After the Induktor put a 0,1 uF Wima Cap parallel.
Then i put my Osc. in front of the LP filter. I got some noise bejond 20mhz (but i gues the noise with my 20Mhz Hameg). After the LP the noise is filtered out (as my intention).
There is still a sinus of 0,1V on the heating line but this is ok i gues!
|
|
| Back to top |
|
|
draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
|
| Posted: Thu Oct 15, 2009 5:57 pm Post subject: |
|
|
| 1031 wrote: | | Nashou66 wrote: | For the G2 mod what current is the max for this line so we don't put to low current rating inductor in there.
Athanasios |
Current is so minimal there, tube takes only few micro amps . So inductors rating is not critical. |
I think it'ss more than that?
| tse wrote: | Heater current for one tube is about 1/4 Amp. Make sure the filter is good for more current than that.
Scott |
|
|
| Back to top |
|
|
Nashou66
Joined: 12 Jan 2007
Posts: 16171
Location: West Seneca NY
|
| Posted: Thu Oct 15, 2009 6:54 pm Post subject: |
|
|
| draganm wrote: | | 1031 wrote: | | Nashou66 wrote: | For the G2 mod what current is the max for this line so we don't put to low current rating inductor in there.
Athanasios |
Current is so minimal there, tube takes only few micro amps . So inductors rating is not critical. |
I think it'ss more than that?
| tse wrote: | Heater current for one tube is about 1/4 Amp. Make sure the filter is good for more current than that.
Scott |
|
Drags I confirmed it with HK-Steve last night, it is in the micro amp range. the heater actually uses more.
Athanasios
_________________
Don't blame your underwear for your crooked ass~ unknown Greek philosopher
"Republicans believe every day is the Fourth of July, but the Democrats believe every day is April 15." --- President Reagan
One Smart Dog!!!
Marquee High Performance Bellows now shipping!!
Marquee Modifications and Performance Enhancement
Marquee C-element and Bellow removal
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
| Posted: Thu Oct 15, 2009 7:47 pm Post subject: |
|
|
| Nashou66 wrote: | | draganm wrote: | | 1031 wrote: | | Nashou66 wrote: | For the G2 mod what current is the max for this line so we don't put to low current rating inductor in there.
Athanasios |
Current is so minimal there, tube takes only few micro amps . So inductors rating is not critical. |
I think it'ss more than that?
| tse wrote: | Heater current for one tube is about 1/4 Amp. Make sure the filter is good for more current than that.
Scott |
|
Drags I confirmed it with HK-Steve last night, it is in the micro amp range. the heater actually uses more.
Athanasios |
series inductor at high-z circuit (like this G-2 circuit on VNB) doesend filter HF-noise wery well. I think (and have done) that noise cleaning with HV-capactor (rated up to 3KV) Is more effective way because cap parallel between G-2 / Gnd gives "route" to Ac (noise voltage) to go ground (so it works like r-c filter) Cap size cannot be too big so that "G-2 kill circuit" still work as it should.. Finding right size cap is key.. 
Inductor that is series to high impedance load (tube) dosend work as lowpass filter (at frequencies that are needet here)
_________________
Marquee 9500LC (Frankenyokes / Thomas electric tubes / HD-10L / +many modīs)
DVDO VP-50
New hobby, Rally
http://www.youtube.com/watch?v=vX2Rtpr1njs
http://www.youtube.com/watch?v=6ZP9FEFXV5c
http://www.youtube.com/watch?v=j065vei6j6s
http://www.facebook.com/pages/JTS-Racing-team/204443719572685
|
|
| Back to top |
|
|
Nashou66
Joined: 12 Jan 2007
Posts: 16171
Location: West Seneca NY
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Thu Oct 15, 2009 11:30 pm Post subject: |
|
|
| 1031 wrote: |
series inductor at high-z circuit (like this G-2 circuit on VNB) doesend filter HF-noise wery well. I think (and have done) that noise cleaning with HV-capactor (rated up to 3KV) Is more effective way because cap parallel between G-2 / Gnd gives "route" to Ac (noise voltage) to go ground (so it works like r-c filter) Cap size cannot be too big so that "G-2 kill circuit" still work as it should.. Finding right size cap is key..
Inductor that is series to high impedance load (tube) dosend work as lowpass filter (at frequencies that are needet here) |
Hmm... not sure how you got to this. I've also spent a lot of time looking at this, and have found just like with the LVPS design, that it's best to use an inductor in series. Without the inductor, you would need very high capacitance to lower that noise, and you're not likely to target the noise at the right frequencies using caps.
With the inductor, you don't need large capacitance. And you would also eliminate the possibility of capacitance overloading the G2 line.
The right inductor and cap would target that frequency and for the most part render it too low to be a problem.
|
|
| Back to top |
|
|
1031
Joined: 22 Mar 2006
Posts: 657
Location: Finland
|
| Posted: Fri Oct 16, 2009 5:17 am Post subject: |
|
|
| mp20748 wrote: | | 1031 wrote: |
series inductor at high-z circuit (like this G-2 circuit on VNB) doesend filter HF-noise wery well. I think (and have done) that noise cleaning with HV-capactor (rated up to 3KV) Is more effective way because cap parallel between G-2 / Gnd gives "route" to Ac (noise voltage) to go ground (so it works like r-c filter) Cap size cannot be too big so that "G-2 kill circuit" still work as it should.. Finding right size cap is key..
Inductor that is series to high impedance load (tube) dosend work as lowpass filter (at frequencies that are needet here) |
Hmm... not sure how you got to this. I've also spent a lot of time looking at this, and have found just like with the LVPS design, that it's best to use an inductor in series. Without the inductor, you would need very high capacitance to lower that noise, and you're not likely to target the noise at the right frequencies using caps.
With the inductor, you don't need large capacitance. And you would also eliminate the possibility of capacitance overloading the G2 line.
The right inductor and cap would target that frequency and for the most part render it too low to be a problem. |
I looked yesterday , but i have lost pictures/details (my computer harddrive crashed a while ago) So i have look that next time when i open my marquee.
But what iīm meaning is that just using series inductor does not clean noise well.
Best way would be put small inductance inductor between 100k and 10k then add some capacitance parallel to c27/100Pf.
Maybe even put one cap after that 10k(r81)
_________________
Marquee 9500LC (Frankenyokes / Thomas electric tubes / HD-10L / +many modīs)
DVDO VP-50
New hobby, Rally
http://www.youtube.com/watch?v=vX2Rtpr1njs
http://www.youtube.com/watch?v=6ZP9FEFXV5c
http://www.youtube.com/watch?v=j065vei6j6s
http://www.facebook.com/pages/JTS-Racing-team/204443719572685
|
|
| Back to top |
|
|
mp20748
Joined: 12 Sep 2006
Posts: 5689
Location: Maryland
TV/Projector: 9500LC Ultra / Super 02 and 03 VIM
|
| Posted: Fri Oct 16, 2009 11:21 am Post subject: |
|
|
| 1031 wrote: | | mp20748 wrote: | | 1031 wrote: |
series inductor at high-z circuit (like this G-2 circuit on VNB) doesend filter HF-noise wery well. I think (and have done) that noise cleaning with HV-capactor (rated up to 3KV) Is more effective way because cap parallel between G-2 / Gnd gives "route" to Ac (noise voltage) to go ground (so it works like r-c filter) Cap size cannot be too big so that "G-2 kill circuit" still work as it should.. Finding right size cap is key..
Inductor that is series to high impedance load (tube) dosend work as lowpass filter (at frequencies that are needet here) |
Hmm... not sure how you got to this. I've also spent a lot of time looking at this, and have found just like with the LVPS design, that it's best to use an inductor in series. Without the inductor, you would need very high capacitance to lower that noise, and you're not likely to target the noise at the right frequencies using caps.
With the inductor, you don't need large capacitance. And you would also eliminate the possibility of capacitance overloading the G2 line.
The right inductor and cap would target that frequency and for the most part render it too low to be a problem. |
I looked yesterday , but i have lost pictures/details (my computer harddrive crashed a while ago) So i have look that next time when i open my marquee.
But what iīm meaning is that just using series inductor does not clean noise well.
Best way would be put small inductance inductor between 100k and 10k then add some capacitance parallel to c27/100Pf.
Maybe even put one cap after that 10k(r81) |
Hey, I expect better from you..
I've found several ways to clean up the G2 to the CRT's. I use several HVPS for the R@D. I've already confirmed the benefits of making these changes, and that's why I've put so much into it. It's been on the shelf for awhile with intent to get back to it later. It's one of those things that works very well, BUT, you first would have to clean up the rest of the video chain before you can really see a difference.
As you know, I don't tweak around adding anything unless I know there's a benefit for adding it. Other than the tants and a very few other capacitors, I love using cheap caps. In fact, most of the electrolytics i use are cheap caps. I use them because I've never seen any benefit in using more expensive caps. I've only been able to see the use for more expensive caps in audio tube amps. So, when I'm adding something, believe me that there's a reason for it.
So if i say as i said so many times before that the biggest source for the noise in a marquee is NOT the LVPS. And that's why I only replace the caps on the 85 volts rails (as Scott eluded to previously). And that's why use up to 24 inductors (beads and coils) on my VIM alone. I also add several on the neck boards.
The problem with inductors is finding the right inductor for the frequency (noise) you want to deal with. This is not easy, mainly because when you deal with inductors, they can also create more noise if not within the right range.
Anyway... you're one of the few people I would love to spend a day with here at the MOD factory. So if you're ever here in the states let me know. plus, we have a joint project we need to get back to (what you sent me). I have one more project to wrap up here in the shop, then I'll get back to you and open a thread on my forum, and we'll go from there..
|
|
| Back to top |
|
|
|
|
Not from filamet mod. That Vim is "diy 2035-03p" and i havent fixed that black issue at that VIM. Vith my another vim (2035-02p) blackīs are ok. But iīm using that modded one because it has better BW.
