CurtPalme.com Home Theater Forum

[Alex2014]

Distinguished experts and amateurs CRT, need your professional help.

Two problems:

1. The projector Vidikron Vision ONE (ultra, april 1999, 1676 hours) periodically brightness / contrast jumping erratically up about 15% in all three tubes.

Defect appears periodically, but often.



2. Noise on the image at all three tubes. Noise is noticeable only on the face of all three tubes at low brightness and contrast. Noise appears as inconspicuous loss of synchronization (analogue video bad connection).

In reality, on the screen at normal brightness 50 and contrast 50 image noise is not noticeable.

Poor connections, video / graphics card to the projector is not.

Checked in various connectivity options for both video card slots via HDMI (VIM_FHD_V3) and BNC (EXT_FHD_V1, HD FURY4).

On menus and tables crosshatch internal generator noises are also visible.



Projector four years was kept in cold storage with temperature difference of minus 25 ° C to plus 25 ° C, in the LC chamber has a little fungus around the screws of metal corrosion.

Guess what to do 100% clean all contacts DEOXIT.

But I wanted to identify the specific cause of these two problems. So I want to do the cleaning steps to verify the elimination of each of the two problems.

Please show me how to start each of the problems?



Sorry for bad english ...

Thank you.



Alex.

[Curt Palme]

I would definitely clean all contacts with DeOxIt as you say, that could solve everything. You may have a bad HVPS, high voltage doesn't like cold and condensation for long periods of time. It may be arcing internally, causing the noise and/or brightness fluctuations.

if not, it could be the VIM or CLM or one of the video neck boards, which can affect all tubes.

Start with the DeOxIt, and please report back.

Cheers!

[Curt Palme]

I would definitely clean all contacts with DeOxIt as you say, that could solve everything. You may have a bad HVPS, high voltage doesn't like cold and condensation for long periods of time. It may be arcing internally, causing the noise and/or brightness fluctuations.

if not, it could be the VIM or CLM or one of the video neck boards, which can affect all tubes.

Start with the DeOxIt, and please report back.

Cheers!

[digitalayon]

I agree with Curt......most likely build-up causing the problem.

[Alex2014]

Hi guys!
Reporting, challenges remain:
1 Periodically brightness / contrast jumps / flickers up to 15% in all three tubes at intervals of a second. Defect appears periodically, but every minute.
2 The noise on the image at all three tubes. The noise is noticeable only on the face of all three tubes at a very low brightness and contrast. Noise appears as inconspicuous as a loss of synchronization or a bad signal when receiving an analog TV RF antenna.

What was done:
First cleaning CLM to remove chips - nothing has changed.
Then cleaned VIM - noise was somewhat smaller, but he stayed and noticeable.
Further cleaning NECK BOARD. After cleaning swap them on the tubes.
The problem remained.
Note that all three NECK BOARD visually look new without a deposit / deposits on the board and components.
The crackling from the HV splitter and HVPS no, sparks on high-voltage connection is not present.
On HVsplittere was little soot.
The rest of the board is not yet cleaned.
What problem can still be?
Replacing HVPS?

Cleaned in three stages:
1. Cleaning isopropyl alcohol toothbrush board
2 then cleaned with cleaning fluid KONTAKT WL (DEOXIT not found)
KONTAKT WL: clean contact surfaces, removes from their surfaces dissolved oxides and most importantly - the corrosion products. Manufacturer: CRC Industries),
3 then cleaned boards and contacts lubricating and cleaning fluid KONTAKT 61 (The preparation forms a thin microscopic film on the treated surface, prevents corrosion and at the same time providing high quality contact, eliminates the possibility of leakage current, has anti-corrosion properties, is a good lubricant).

Thank you, Alex.

[stridsvognen]

Do you have the ground strap to the back plate Convergence/ stigmator board.?

Noise at low level is normal, a standard Marquee, or any CRT for that matter have noise of different kind, the ground strap can help on some Marquee machines.

Do you have a picture of your HV parts, splitter cables and so on, lets see how dirty it is, i always clean the splitter HV cables, and sometimes the tube bell if its to full of that black conductive stuff it collects.

[Alex2014]

Thank you, questions are clear and logical.
Yes, all three bolted ground strap to the back plate Convergence / stigmator board.
Other earth wiring from NECK BOARD is also connected as originally from the factory, the projector to me nobody would climb.
Also on NECK BOARD on the recommendation of TIM / bulletin VDC bent from board to his black earthen cables, but did not help get rid of the noise:

Thanks for the advice on cleaning high-voltage parts. I will try and will report the results later.
The question is, how much time the projector should be turned off, so as not to struck the high residual voltage from HVPS (34,9KV) / other safety precautions when cleaning HVsplitter?

Alex.

[Curt Palme]

At some point you will need to start swapping boards.

-VIM
-LVPS
-HVPS


Since all 3 tubes are doing it, I can't see it being the neck boards.

I am selling off many Marquee parts for cheap, so if you need a working tested board, let me know.

[Curt Palme]

At some point you will need to start swapping boards.

-VIM
-LVPS
-HVPS


Since all 3 tubes are doing it, I can't see it being the neck boards.

I am selling off many Marquee parts for cheap, so if you need a working tested board, let me know.

[Alex2014]

Thank you, Kurt.
To you will turn in the first place. If the problem persists, I will change the boards:
-LVPS
-HVPS
Alex.

[Alex2014]

Thank you, Kurt. Talking to you in the first place. If the problem persists, I will change the board.

[Nashou66]

For the noise one thing you can try on the VNB's is lifting the two black heater (HTR1) wires that go over the op amp up off the op amp if they are pushed down on it. Those wires introduce noise to the op amp .

Now for the systematic Brightness increase and decrease it might be a bad VNB. So disconnect one at a time by pulling the bunch of black wires(umbilical cord) from the VNB one at a time and turn on PJ. If the issue is still reconnect that VNB and remove the next, and test again. If it still does it after you have removed each Umbilical cord and tested then it is not a VNB. But if the issue stops after one of the VNB's are removed then that VNB is the problem.

Athanasios

[Curt Palme]

BTW, also try Nash's suggestion. One VNB could indeed affect the other tubes as well (no coffee when I posted!)

[Curt Palme]

BTW, also try Nash's suggestion. One VNB could indeed affect the other tubes as well (no coffee when I posted!)

[draganm]

I've seen many newer tubes now come with the 3 wires to the rear heat-sink all braided together in a "pony-tail, I remember Nash's Longbow had all sorts of noise from this. If the vertical-convergence, Stigmator wires are braided together then un-wind them. they can cross each other at perpendicular angles but should never be wound around each other.

[dvh99]

where is your g2 wire going to?

[stridsvognen]

[stridsvognen]

Hey wait a sec. Thats not a 9" tube, its a 8" tube and 8500 neckboard

[Melifluonze]

I had a problem with my VV1 too. Same thing with the contrast, except that mine was low and jumped up and went away (no picture).

Turned out to be the HVPS failing...

-M

[gjaky]

[stridsvognen]