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Wire length (with completed pics of CP)

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RandyT:

--- Quote from: NoOne=NBA= on February 17, 2005, 09:24:56 pm ---I've heard RandyT mention 15' as the maximum several times.

I'm not sure if that's 15' TOTAL, including the run to the PS/2 port, or just 15' for the controller-to-encoder run though.

--- End quote ---

Heh, that's just me erring well on the side of caution.

I tried an extreme test one time by running one KeyWiz input to about 50' of 30ga Kynar (thin wire wrap wire) and it still activated the input every time without fail.  Now, this doesn't mean that 30 of these constantly modulating next to each other won't have crosstalk or other interference problems, but it did work over that distance.

So the rule is:  Shorter is always better, but don't go shorter than you need to until you know it will be a problem. :)

RandyT

ShinAce:
Transmission speed is close to the speed of light, some 300 000 km/sec.

Assuming 60 fps, you'd need over 16 million feet of wire for each switch to lag by 1 frame. So technically, it might lag once you get over 8 million feet of wire. So obviously the length of the wire is not an issue.

However, shielding is important. The air carries a 60 hertz signal, EVERYWHERE, thanks to our power grids. So if you have 500 feet of exposed wire, you might pick up enough electrical noise from the air to cause problems. The only way to prevent it is to use shielded cables and shunt the shield to ground.

Personally, I'm working on a new stick that's connected to the encoders via monitor extension cable. I have 6 and 10 footers, which means I can get up to 20 feet of wire between me and the console. I've got a pair of headphones with a 16' cord. They sound great, and audio signals are much more flaky than digital signals.

RandyT:

--- Quote from: ShinAce on February 18, 2005, 07:32:17 pm ---Transmission speed is close to the speed of light, some 300 000 km/sec.

Assuming 60 fps, you'd need over 16 million feet of wire for each switch to lag by 1 frame. So technically, it might lag once you get over 8 million feet of wire. So obviously the length of the wire is not an issue.

--- End quote ---

Actually it can be, but lag has nothing to do with it.  Wire has resistance,. Thinner wire has more resistance.  Long and thin wire has even more resistance.

Resistance can lead to voltage/current drop, which can lead to  improper operation of digital circuits.  Long wires, especially shielded ones, can also have capacitance, ringing and other nasty problems.

Like I said, shorter is better, but how short depends on the particulars of your installation.

RandyT

cholin:
Well it all comes down to the wire he's using then.  Either way, if he runs 100 ft of wire from his Control Panel to his computer, he will still be fine, assuming the wire is straight.  Wire is made for this kind of stuff.  Sure, it might mess up, but thats after a while of abuse.

ShinAce:
Even 30 gauge wire is only 1 ohm per 10 feet, and 30 gauge is ridiculously thin.

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