Curt,
RG6 will certainly pass all the signals that you would ever want to send to a projector. Since it has a bandwidth capable for CATV it can easily pass all baseband video signals.
The problem with RG6 isn't with its bandwidth capabilities, it's the fact that it's stiffness makes it a little difficult to work with and it is physically large, so it will fill a conduit fairly fast. It can also be a little difficult to terminate in the quad shield variety. In this case you may need to terminate in 'F' type and convert using adapters - not very elegant, but workable.
You didn't specify what your intentions are with respect to the projector scaling and switching duties. This can make a big difference in the cable requirements you need to run..
A lot of todays small digital projectors provide their own switching and scaling. If you plan on using these internal features you will be want to provide sufficient cables to feed all the inputs. On the other hand if you will be switching and scaling at your equipment rack, you can get away with a single RGBHV 5 wire cable feeding the projector.
For this cable you can certainly run 5 RG6 cables and terminate them and it will work beautifully. If you're not capable, have someone terminate them for you or purchase them already terminated and perhaps use an adapter to convert to the plug type used on your projector. They also sell some nice flexible RGBHV cable with 5 tiny color coaxial cables inside (preferred method). Shouldn't be too expensive for 25 feet.
You should also run a few CAT5 cables for future control duties like remote on/off, screen and curtain motors, etc.
On the other hand if you plan on using the projector itself for scaling and switching, you will need a lot more cables. It depends on your equipment plans and the number on different switchable inputs on the projector. Likely candidates would be:
x2 RGBHV cables,
x1 S-Video cable,
x1 RG-6 cable,
x1 SVGA cable,
and a couple CAT5 control cables.
No doubt you already know this, but perhaps I should explain what is meant by an RGBHV cable (ignore this if you already know).
The RGBHV cable is actually 5 individual 75 ohm video coaxial cables usually terminated in BNC type connectors (a projector standard). The cable usually has an outer jacket around 5 smaller individually color coded coaxial cables. The RGBHV stands for Red/Green/Blue/Horizontal/Vertical. This is a standard in the professional video world. The RGB cables carry the video information for their respective color and they are synced by the separately transmitted horizontal and vertical sync pulses. You may of course use any or all these five 75 ohm cables for other video standards.
These other standards include four wire RGBsync (which is another standard where the horizontal and vertical sync for the RGB information is combined in a single signal and separated at the projector), or three wire RGB (which is a standard where the sync is combined with the green information signal and then separated at the projector, also known as "sync on green"), or three wire Y/Pb/Pr (which is a DVD player standard output also known as component).
My point is that even though a DVD player may require a 3 wire component cable, I would always install the 5 wire cable and use 3 wires only. You never know what the future will hold.
Here are the possible uses of the cables I mentioned.
Cable 1 = RGBHV for DVD player - using three wire component. This cable may also be used in the future from a scaler using all 5 wires.
Cable 2 = RGBHV for Satellite HDTV receiver - using three wire component output.
Cable 3 = S-Video for NTSC Satellite receiver.
Cable 4 = RG-6 for VCR player - composite yellow output.
Cable 5 = SVGA for future HTPC feed (or any computer feed).
Cable 6 = Cat5 for future control.
Cable 7 = Cat5 for future control.
I would certainly put a pipe in the ceiling to pass all your cables through, so you can add or subtract at a later date. Don't forget to put a 'fish' wire in the pipe.
brucek
