I would like to mount my LCD input control boards remotely, there is a 20 wire connector going between the LCD control board (connected to the LCD via FFC cables) and the input / tuner boards. If I use a 25 ft parallel cable to extend the wire will I notice a huge drop in quality?

The parallel cable I got is a 25 conductor straight through - not the IEEE complient 18 pair cable which is what is found in most printer cables.

I'm just wondering if that 25' is going to kill my quality.

Thanks,
Tom

Personally I believe you would have a large degradation of the signal.

How long do you think I can extend them w/o a problem? I'm going to put female ports on the projector box and the control box so I can put any length of cable in between -- I started at 25' to make sure I didn't short change myself.

Thanks,
Tom

The LCD control board (IE the one that the VGA/DVI cable connects to) should NEVER be extended if it can be at all avoided. The parasitic indictance/capacitance will alter the signal, and you'll get unpredictable results, not to mention the potential for interference. These cables more or less directly control the transistors, so they're really sensitive to changes in capacitance/inductance. At best, the result will be a much slower response time.

However the LCD button control panel can be extended quite far, if you like. These aren't so much signal wires as they are switches, so they're nowhere near as sensitive. For this, I think that you should be able to extend them without problems. This can allow the LCD control buttons (power, menu, auto etc.) to be quite far from the actual LCD itself.

Ehh, not the answer I wanted to hear.

I didn't want to have to mount all of the inputs in my box and connect them hanging from the celiing, but from the way you're making it sound it would be better to extend the signal cables there than the LCD cable.

Has anyone actually tried this? I have a Samsung MP150 which has 2 input boards and a control board. The control board is connected to the LCD with 2 FFC cables and the 2 input boards are what I want to extend.

On a second note, how far can I extend my ballast away from my bulb?

so you don't have a problem running the LCD control board signal cable and PJ power cable up to the ceiling, but you had a problem running a VGA/DVI cable up there? I don't get it. sounds like a lot more work to extend the LCD controller cable when you have to run wires up there anyway

You should have no problems up to several or maybe five feet. I believe others have gone farther still but you'll have to test to verify distances beyond several feet. At least I would test before commiting.

If you have pictures that might help clarify just what you intend to do also.

The thing is that I can run one DB25 cable up to control the LCD, instead of running up one VGA, one RCA, one S-Video.

Then I can hook all my devices to the back of this 'control box'.

Click to view attachment

So I would have three wires running between the projector and the control box.
LCD Control (25 Pin Parallel Cable) / 120V or 12V Depending on my Fan Choice / and the two wires from the ballast to the Bulb (I read that 600V rated wire would work for this purpose).

But with the quality issues you speak of, I might just mount this 'control box' on the bottom of my projector and hang it up instead of putting it with my Sony 5.1.

Edit: The only things mounted in that box now are the ballast and the front panel assembly -- nothing is currently wired up, so feel free to tell me this is a retarded idea and scrap it.

Tom

I have 15' distance between my core ballast and the bulb on my first PJ. Absolutely no problems. I used #14 wire.

Thanks bevo77, at least I know I can mount that remotely. My concern with the ballast was weight, that little sucker is heavy.

Tom

I do seriously think that you'd be better off running your signal wires to the box.

Another risk with running the control signal is static electricity. Get one zap from that DB25 cable, and kiss your LCD goodbye. Even a zap that you can't even feel is more than enough to cook those transistors.

You should be able to get a reasonable bundle with the signal wires though, but run the ballast output separately, or be prepared to have interference issues with the signal.

I like your control box, you should be able to run the button panel remotely, with no problems at all, just a matter of extending the control wires. Keep it and the ballast together.

Those ballasts are quite often a good distance from the lights that they control. For example, I was just in a building where all the HID ballasts were in one large box along one wall of the building, with the lamps in overhead fixtures, some quite a distance away. (The ballasts were together so that they could all be fan-cooled together.)

Sounds like a plan, thanks for the tips. I think that's what I'll do.

Tom