CurtPalme.com Home Theater Forum

[jaredjaric]

Hope someone can point me to the right direction.

I have HV issues with my cinemax.

After two splitters ,one eht board and three quads, i am scared of putting in my last quadrupler.

This pj has been having shutdown issues for the past month already.

Smps and h boards were swapped in already , eht boards replaced and 17 volts and P201 raster adjusted as per service manual.

The Pj would run great for four hours then would go into shutdown, bringing down first splitters then an eht board then three quads.

This is becoming a very expensive ordeal for me.

[Curt Palme]

It's definitely strange, but there's nothing outside of the 3 HV components (EHT board, quad and splitter) that can cause failures of these three units. The later quadruplers and splitters are VERY unreliable due to Barco changing their silicone potting compound to seal the HV parts in. Over time it goes conductive, and it doesn't seem to be related to the actual hours used, only the time elapsed since the quad or splitter was made. If the quad shorts out, the EHT board can dies along with it, but that doesn't happen all the time.

I'm in the process of testing some quadruplers, splitters and EHT board. Maybe I should send you a full, tested set of 3, replace all three, and see if that lasts. I just can't see anything else being the problem causing the failures.

[Curt Palme]

It's definitely strange, but there's nothing outside of the 3 HV components (EHT board, quad and splitter) that can cause failures of these three units. The later quadruplers and splitters are VERY unreliable due to Barco changing their silicone potting compound to seal the HV parts in. Over time it goes conductive, and it doesn't seem to be related to the actual hours used, only the time elapsed since the quad or splitter was made. If the quad shorts out, the EHT board can dies along with it, but that doesn't happen all the time.

I'm in the process of testing some quadruplers, splitters and EHT board. Maybe I should send you a full, tested set of 3, replace all three, and see if that lasts. I just can't see anything else being the problem causing the failures.

[jaredjaric]

I agree that the new quads 768xxxx are not reliable, but 4 to 8 hours run time or three quads in a week is too much.

really need to figure out the cause of it all before i can put in new quads.

[Tom.W]

Did you read this ?

http://www.curtpalme.com/docs/BarcoServiceBulletin_R762716_New_EHT.pdf

[jaredjaric]

[Hulio]

No, you definitely don't need to put a old style quad in your machine.
Tom is pointing out that not every combination of EHT-splitter-quad-frame will work, like seen on the last page of that document.
If your parts have the following numbers, the combination is ok:
EHT - 7627165
Splitter - R762718
Quad - R763368
Frame - R763146

[Curt Palme]

As I explained to jared, I've had lots of issues with all of the new style quads and splitters over the last few years. They die all the time, and in the last year I've even had them go bad in <1000 hour Cine 9/909, so to me, failure of the later style quads isn't a surprise at all, ditto for the later Hv splitters, as Hulio listed above. The problem is the potting compound, which goes conductive over time regardless of the amount run. I'd almost argue that a constantly used 909/Cine 9 projector may last longer due to less moisture being within the projector, but that's just a guess. I've seen some well used 909s with 30K+ hours on them, used 24/7 with original quads in them, so not all are bad I guess.

The only combination that does not work is a new type quad with an old type EHT board. that will usually blow the EHT board within seconds.

All other combinations work fine. There are about 6 different models of splitters, from Barco 700, 800, 1208, 808 and 909/Cine series, all of which are interchangeable.

The newer splitters tend to arc internally, causing pulsing. Not always, they can cause EHT shutdown as well, just like the quads. The EHT boards, old or new, seem to be pretty solid.

Why Jared's quads are being eaten by one of his sets is beyond me. The whole HV section is isolated pretty much from the rest of the set. If the DC supply into the EHT board went high (or low), I suspect that the set would go into EHT shutdown mode, as Barco's sensing circuitry is good in all of their sets.

I'm sending him a full set of 3 HV parts on Monday. I've suggested that he send me his bad quads and splitters for me to test here, to see if I can find a common denominator. Keep in mind that even if a tube was drawing slightly excessive current, I've got lots of planetariums out there running 909s, at a contrast of 90-95, which puts a strain on the HV section, and if the HV section were poorly designed, those planetariums would be going through quads every week. They don't, so this may all be a coincidence, or simply age related. It's still a mystery though.

[Curt Palme]

As I explained to jared, I've had lots of issues with all of the new style quads and splitters over the last few years. They die all the time, and in the last year I've even had them go bad in <1000 hour Cine 9/909, so to me, failure of the later style quads isn't a surprise at all, ditto for the later Hv splitters, as Hulio listed above. The problem is the potting compound, which goes conductive over time regardless of the amount run. I'd almost argue that a constantly used 909/Cine 9 projector may last longer due to less moisture being within the projector, but that's just a guess. I've seen some well used 909s with 30K+ hours on them, used 24/7 with original quads in them, so not all are bad I guess.

The only combination that does not work is a new type quad with an old type EHT board. that will usually blow the EHT board within seconds.

All other combinations work fine. There are about 6 different models of splitters, from Barco 700, 800, 1208, 808 and 909/Cine series, all of which are interchangeable.

The newer splitters tend to arc internally, causing pulsing. Not always, they can cause EHT shutdown as well, just like the quads. The EHT boards, old or new, seem to be pretty solid.

Why Jared's quads are being eaten by one of his sets is beyond me. The whole HV section is isolated pretty much from the rest of the set. If the DC supply into the EHT board went high (or low), I suspect that the set would go into EHT shutdown mode, as Barco's sensing circuitry is good in all of their sets.

I'm sending him a full set of 3 HV parts on Monday. I've suggested that he send me his bad quads and splitters for me to test here, to see if I can find a common denominator. Keep in mind that even if a tube was drawing slightly excessive current, I've got lots of planetariums out there running 909s, at a contrast of 90-95, which puts a strain on the HV section, and if the HV section were poorly designed, those planetariums would be going through quads every week. They don't, so this may all be a coincidence, or simply age related. It's still a mystery though.

[redfox001]

Could this be caused by a shorted tube?

[jaredjaric]

[quote="redfox001"]Could this be caused by a shorted tube?[/quote

Possible,

But from two different Pjs ,and both have dying quads is very irritable

[jaredjaric]

Curt,

Would an old 701s quad with an 808 eht combo work on the 909?

[Curt Palme]

The quad will work fine, but the EHT won't, I don't think. Take a look at the two rectangular black blocks near the middle top of the board. Those are optoisolators, and they are separated by a couple of cm in the new style EHT, and are almost touching each other on the old style. There's a jumper wire that has to be installed on the back of the board in order for the two types of EHT boards to be compatible, I can email that to you tomorrow.

[Curt Palme]

The quad will work fine, but the EHT won't, I don't think. Take a look at the two rectangular black blocks near the middle top of the board. Those are optoisolators, and they are separated by a couple of cm in the new style EHT, and are almost touching each other on the old style. There's a jumper wire that has to be installed on the back of the board in order for the two types of EHT boards to be compatible, I can email that to you tomorrow.

[CasetheCorvetteman]

[quote="jaredjaric"]

[jaredjaric]

[quote="CasetheCorvetteman"][quote="jaredjaric"]

[CasetheCorvetteman]

Hmmmm....

[jaredjaric]

Just an update,

So the Cinemax is replaced with a 909 , both units have hV issues. They are mostly eating quads and splitters.
Only one eht down. Mot spares are used , except for one quad claimed as new/open box.

The 909's quads came from a 919 , and the splitter from my spares.

black bands in the middle when adjusting focus, fixed by 17v readjustments.

So for every HV part changed the 17 volt drops quite a bit i this 909.

Green tube is focusing normally now, and the whole video is not pulsing anymore.

HV seems stable except for some little clicks once in a long while.

PQ is great now and have exceeded 6 hours of viewing, plus hours of readjustments.

New issue with the 909 is left and right adjustments are impossible.

Convergence is good either x or y axis.

The sides needs keystone adjustment and i need to fix the wavy odd side.
so far the the RGB is well aligned or converged.

On what board does this east to west adjustment belong. i swapped a convergent board from the 919 already and still no changes.

[redfox001]

The vertical board.

[jaredjaric]

Thanks, Redfox.

always the cool guy.

[redfox001]

Thanks! Remember that Curt is the real expert here. I am just like you a hobbyist