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I recently had the opportunity to install a new Zenith Pro895X High Definition CRT Front Projector for their home theater. (Note that the link takes you to the page for the Pro900X, which is essentially the same projector).
As I set up the projector, I took pictures to show some of the steps involved in installing a CRT front projector. It's a lot of work, but in the end it's worth it, as nothing else can touch the picture quality that's possible in a quality CRT projector.
My friends floor mounted the projector inside a custom built coffee table. They are using a motorized 96" wide (120" diagonal) 4:3 Da-Lite screen. The projector is being fed a 480p signal from a Videon Omega One line doubler.
Here's the projector, with the covers removed.
Since the projector is configured at the factory for ceiling mounting, the yoke wires have to be reversed, in essence flipping the image on the CRTs so that the picture isn't upside down and backwards when the projector is floor mounted!
Here's the convergence board, flipped up to gain access underneath.
Here's some of the yoke wires (the red and blue ones). They have to be reversed in order to use the projector in a floor mount configuration.
Here's a better shot of those yoke wires.
Here's a shot of the projector's innards.Those gray things that look like space ray guns are the cathode ray tubes (CRTs). The black box in the left of the picture (over the red CRT) is the electrostatic focus and screen adjustments. Those thick red wires you see carry approx. 20,000 volts to the CRTs, so one has to be careful not to touch them while adjusting things!
Here's a shot of the front of the projector. Those cannon-looking things are the lenses. There's one mounted on each CRT. In this picture there are dust covers on the lenses. The lenses from left to right are for blue, green, and red respectively. Those gray shims behind the lenses are pre-set for a 80" wide screen. Since my friend has a 96 inch screen, those shims have to be removed, as illustrated in the next few pictures.
In order to remove the shims, the lenses have to be removed. In this picture I removed the green lens, which sits on the floor. The shim is right behind the lens on the floor.
Here's a close up shot of the green CRT with the lens removed. There is a coolant cover over the CRT face, yes there's actual liquid in there! It keeps the CRTs from getting too hot when the projector is in operation.
In this picture I've replaced the green lens (notice how the gray shim is removed), and I've removed the red lens and its shim.
And ditto for the blue lens.
All the lenses are back in place, with the shims removed. You can just see the shims lying on the floor in front of the projector.
Now it's time to place the projector in the coffee table. We carefully measured the distance from the screen and placed the table and projector at the proper distance from Bob's screen. We also centered the projector so that the green lens is centered in respect to the screen. Soon we'll be firing this baby up and adjusting it!
The first thing I did after powering up the projector was to aim and focus the lenses. Once they were focused, I put a convergence grid up. The next task is to adjust geometry and convergence. Geometry is adjusting the image so all the lines are straight and the squares are square. Convergence is getting the lines from the red, green, and blue CRTs to converge on the screen so that you'll see white lines, instead of separate red, green and blue lines like you see in the picture. This process takes several hours and lots of trial and error.
Note that the grain in the picture is due to the camera (the room was dark for the screen shots), and not the projector. The real images look a lot better than these pictures can show!
Here's a resolution pattern from Ovation Software's AVIA DVD. I put this up after completing convergence, just to see what this baby is capable of! The picture doesn't do it justice, this projector does a fine job!
Here's the projector, all converged and ready to have the covers put back on!
And here it is with the covers back in place!
Next, we put the top on the coffee table.
The front of the coffee table closes up, hiding the projector when it's not in use.
Here's a screen shot from The Fifth Element-Superbit Edition. It looks even better in real life than in the picture.
Here's a screen shot from Disney's Toy Story 2. Buzz Lightyear never looked better on a large home theater screen!
As I set up the projector, I took pictures to show some of the steps involved in installing a CRT front projector. It's a lot of work, but in the end it's worth it, as nothing else can touch the picture quality that's possible in a quality CRT projector.
My friends floor mounted the projector inside a custom built coffee table. They are using a motorized 96" wide (120" diagonal) 4:3 Da-Lite screen. The projector is being fed a 480p signal from a Videon Omega One line doubler.
Here's the projector, with the covers removed.
Since the projector is configured at the factory for ceiling mounting, the yoke wires have to be reversed, in essence flipping the image on the CRTs so that the picture isn't upside down and backwards when the projector is floor mounted!
Here's the convergence board, flipped up to gain access underneath.
Here's some of the yoke wires (the red and blue ones). They have to be reversed in order to use the projector in a floor mount configuration.
Here's a better shot of those yoke wires.
Here's a shot of the projector's innards.Those gray things that look like space ray guns are the cathode ray tubes (CRTs). The black box in the left of the picture (over the red CRT) is the electrostatic focus and screen adjustments. Those thick red wires you see carry approx. 20,000 volts to the CRTs, so one has to be careful not to touch them while adjusting things!
Here's a shot of the front of the projector. Those cannon-looking things are the lenses. There's one mounted on each CRT. In this picture there are dust covers on the lenses. The lenses from left to right are for blue, green, and red respectively. Those gray shims behind the lenses are pre-set for a 80" wide screen. Since my friend has a 96 inch screen, those shims have to be removed, as illustrated in the next few pictures.
In order to remove the shims, the lenses have to be removed. In this picture I removed the green lens, which sits on the floor. The shim is right behind the lens on the floor.
Here's a close up shot of the green CRT with the lens removed. There is a coolant cover over the CRT face, yes there's actual liquid in there! It keeps the CRTs from getting too hot when the projector is in operation.
In this picture I've replaced the green lens (notice how the gray shim is removed), and I've removed the red lens and its shim.
And ditto for the blue lens.
All the lenses are back in place, with the shims removed. You can just see the shims lying on the floor in front of the projector.
Now it's time to place the projector in the coffee table. We carefully measured the distance from the screen and placed the table and projector at the proper distance from Bob's screen. We also centered the projector so that the green lens is centered in respect to the screen. Soon we'll be firing this baby up and adjusting it!
The first thing I did after powering up the projector was to aim and focus the lenses. Once they were focused, I put a convergence grid up. The next task is to adjust geometry and convergence. Geometry is adjusting the image so all the lines are straight and the squares are square. Convergence is getting the lines from the red, green, and blue CRTs to converge on the screen so that you'll see white lines, instead of separate red, green and blue lines like you see in the picture. This process takes several hours and lots of trial and error.
Note that the grain in the picture is due to the camera (the room was dark for the screen shots), and not the projector. The real images look a lot better than these pictures can show!
Here's a resolution pattern from Ovation Software's AVIA DVD. I put this up after completing convergence, just to see what this baby is capable of! The picture doesn't do it justice, this projector does a fine job!
Here's the projector, all converged and ready to have the covers put back on!
And here it is with the covers back in place!
Next, we put the top on the coffee table.
The front of the coffee table closes up, hiding the projector when it's not in use.
Here's a screen shot from The Fifth Element-Superbit Edition. It looks even better in real life than in the picture.
Here's a screen shot from Disney's Toy Story 2. Buzz Lightyear never looked better on a large home theater screen!
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Guess what projector my friend replaced with the Pro895X? You got it, a Pro851X. For a NTSC-only, composite-only unit it did a great job. My friend got 7 years of heavy use out of it. He's giving it to a relative so I'm going to get the fun task of setting it up in a year or so. In the meantime he's really enjoying his 895. Now he realizes why I prefer anamorphic DVDs, now he does too! 
ops: , I didn't notice the date.4 years ago you couldn't touch a clean 8 incher for under $4K. things sure have changed a lot and the bulb-machines have come a long way since then. It's to the point where people are happy enough with a DLP/LCD and willing to forego that last 20% of pic quality to avoid the size and complexity of CRT. Oh well, Analog has been the domain of hard-core purists for at least 2 decades since CD came out. One thing is for sure, you wouldn't still be on your first bulb after 4 years only a vacuum tube can do that 
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