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jantje112
Joined: 17 Jul 2006
Posts: 328
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| Posted: Thu Nov 15, 2007 7:48 pm Post subject: Marquee HV Splitter. How to connect? |
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Hello Folks,
On my marquee splitter there's no sign on what's the right way to input the 3 tube hv wirings and which one is the input from the main hv lead (of the hv PS)
Can someone give me a hint on how to connect it?
Thanks!
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PaulB
Joined: 26 Oct 2007
Posts: 359
Location: Bonnie (but rainy) Scotland
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| Posted: Thu Nov 15, 2007 8:04 pm Post subject: |
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Take a close look at the gray box that the leads fit into, on the side it should be marked "IN" where the main power HV lead goes.
Looking from the front (the tube end) of the projector as if its sitting on the floor as if floor mounted, "In" is at the bottom-left.
The tube leads can fit in any old how but generally fit best as left-blue, middle-green and right-red as per the tube layout.
Paul
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Zebu Fellenz
Joined: 21 Dec 2006
Posts: 2567
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| Posted: Thu Nov 15, 2007 8:48 pm Post subject: |
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I shouldn't matter how it is connected as internally all four connections are the same.
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draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
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| Posted: Thu Nov 15, 2007 11:50 pm Post subject: |
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| Zebu Fellenz wrote: | | I shouldn't matter how it is connected as internally all four connections are the same. |
ok, this is the second time this week that this OPINION has been posted here and I can't stand it any longer. I asked an EE about this and he had a hunch but we busted out the mutil-meter to prove a point. Measuring from the IN to any of the out's gives 22Kohm. Measuring from any of the outs to another out shows 44Kohm. What does this mean you ask? Well there's resistors in line. When you go from the IN to any of the outs your grabbing only 1 resistor. When you use one of the out terminal as an in, then 2 of your tubes Anode plates will be getting less voltage than they were dseigned to run on. 
So, just to be clear, there is only one HV IN on the splitter, and there's 3 outs. It doesn't matter what order you hook up the tubes on the out side but you better be using the terminal marked IN for the lead from the high voltage supply.
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Joust
Joined: 05 May 2006
Posts: 2429
Location: Almonte, Ontario, Canada
TV/Projector: Marquee 8501LC
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| Posted: Thu Nov 15, 2007 11:59 pm Post subject: |
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I can accept that.
I deffer to your greater logic. 
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draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
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| Posted: Fri Nov 16, 2007 1:14 am Post subject: |
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well part of me is wondering who the experts were who said it didn't matter? but I think it's best to leave off names and protect the guilty. 
I remember setting up a machine one time where the Red tube was focusing really badly with fat grid lines. It was a freshly re-tubed and MP modded 8500 so I knew the neck-board was good. It took me forever to locate why, the splitter Anode leads was mixed up. At the time I didn't give it any more thought as to why but it was nice to confirm it today with real measurements. I don't know if doubling the resistance to a tube would cut the 34Kv in half, but it would certainly not deliver the correct voltage to that tube. Hopefully, this thread will get people to check their Marquee's and make sure the HV lead from the power supply is in the right place.
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Joust
Joined: 05 May 2006
Posts: 2429
Location: Almonte, Ontario, Canada
TV/Projector: Marquee 8501LC
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| Posted: Fri Nov 16, 2007 1:25 am Post subject: |
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Zebu Fellenz
Joined: 21 Dec 2006
Posts: 2567
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| Posted: Fri Nov 16, 2007 1:31 am Post subject: |
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I stand corrected,
However I've never had any problems with my Marquee with the in plugged into an out and an out plugged into the in.
Mine isn't labeled at all so maybe mine is special
I would still do it the way draganm says, if it says IN you should run the IN cable into it.
Why don't we settle this once and for all and cut one open and see what it looks like.
Erik
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Joust
Joined: 05 May 2006
Posts: 2429
Location: Almonte, Ontario, Canada
TV/Projector: Marquee 8501LC
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| Posted: Fri Nov 16, 2007 1:56 am Post subject: |
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I'll measure mine. and report back.
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Zebu Fellenz
Joined: 21 Dec 2006
Posts: 2567
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| Posted: Fri Nov 16, 2007 2:38 am Post subject: |
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Thanks Joust,
Does yours have one connector labeled IN
Erik
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Joust
Joined: 05 May 2006
Posts: 2429
Location: Almonte, Ontario, Canada
TV/Projector: Marquee 8501LC
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| Posted: Fri Nov 16, 2007 3:15 am Post subject: |
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OK got my Splitter out. You can clearly see the "IN" on the right side. In fact its labeled quite clearly.
The IN has a 3.3K resistor to each of the tube out points.
So as Draganm states, If you put the PS in the wrong point, one tube will get the correct voltage but the other two get something less. The plate on the tube draws very little current so it does work, but obviously its not optimal and probably accounts for the noise I was hearing from my splitter because it was wrong..... 
I'll include a schematic of the splitter i just drew up.
| Description: |
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101.98 KB |
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5812 Time(s) |
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| Description: |
| Schematic of the Marquee HV splitter |
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10.51 KB |
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5813 Time(s) |
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JustGreg
Joined: 07 Mar 2006
Posts: 3098
Location: Kenosha, WI
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| Posted: Fri Nov 16, 2007 3:27 am Post subject: |
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Oh hell....now I have to check mine. Caaaaaaaan't leave anything alone can we.  I do have noise that is easiest to see looking in the lenses. I don't really notice it on the screen but it's been doing that since day one...so I really don't have a comparison. The noise I see in the lenses has always bothered me but I thought, and still do think, the problem goes deeper than having the HV primary in the wrong splitter location. It's worth checking although I'm about 97% sure I have it right.
Good info tho guys. Such a seemingly insignificant component and it can have an identifiable effect on the machines performance.
Greg
_________________
Greg
"Is it ignorance or apathy? Hey, I don't know and I don't care!" --Jimmy Buffett
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draganm
Joined: 08 Mar 2006
Posts: 8990
Location: Colorado
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| Posted: Fri Nov 16, 2007 5:30 am Post subject: |
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| JustGreg wrote: | | Oh hell....now I have to check mine. Caaaaaaaan't leave anything alone can we. Greg |
LOL, that is too true. Funny thing is I haven't done anything to my personal 8500 in months. Last thing I did was plug in the new Moome HDMI card. Greg some degree of noise on CRT is normal, the MP mods get rid of 90% of it so hopefully we'll be able to actually buy those again someday.  For a cheap and easy reduction to some of the noise, replace the cheap VIM to Neck-board mini-coax with high quality mini-Belden's. I think that Ampro/ Pirate guy on the forum was making and selling these in sets of 3.
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jantje112
Joined: 17 Jul 2006
Posts: 328
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| Posted: Fri Nov 16, 2007 7:01 am Post subject: |
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My splitter is a complete blank. Nothing is mentioned on it! So i guess I try some measurements with the multimeter also.
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