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1.4mm Thick Gigabit Ethernet Cable
TheIonix writes "Flat network cables aren't anything new, but I'm pretty sure ones like this are. Japanese accessory king Elecom today announced the "LD-VAPF/SV05" network cabling, coming in at 1.4mm thick." Also here's their press release if you can read Japanese.
I'm not sure if it's out yet or not, but Flatwire has talked about this at least a year ago.
If the pics are accurate, and you can really shut the window (sorry I don't read Japanese), then this is some cool stuff. I can see it being used to hide cabling and make it less obtrusive.
Other than that, they had better be selling it for close to normal cable prices, or I can't think of anyone who would buy very much of it.
"We don't know what we are doing, but we are doing it very carefully,..." Wherry, R.J. Personnel Psychology (1995)
Im guessing they took that into consideration and have developed it to withstand physical damage and such. From the looks of it, it can be closed in a door and have no damage, and walked on with no damage. Hopefully you are wrong and they got this right so I can finally run cable from room to room and be able to close my door.
I have worse karma than M$.
the whole point of making such announcement would be that you would have solved that shielding problem.
the real novelty of this thing(if you watch the pics) is that you can run it through thin places(like windowstills.. no need to bore a hole to the wall).
world was created 5 seconds before this post as it is.
It's not just crosstalk. Twisting improves "Common Mode Rejection" because the twists cause any interference to be picked up with opposite polarity on any signalling pair.
Obviously, IANA EE.
No, the twisted wires aren't twisted to cut capacitance between those two wires. It's the crosstalk between parallel channels that you want to cut down on. The twisted pair itself is basically a poor-man's transmission line, with characteristic impedance of 93 Ohm or thereabouts, depending on the twist pitch. Each twisted pair contains signal and ground (ie, it's return), and ideally should have zero net current flow within the pair (like coax). Ie, the current flow in the pair goes 'there and back again' for the signal/ground. By twisting them you effectively couple them together better, so they're less likely to crosstalk to the other pairs, either through capacitive or mutual inductuve coupling.
While there is definitely capacitance between the two twister pair lines, there is a roughly constant mutual inductance that lets it approximate a tramsission line w/ real impedance (ie, no filtering to first order). This is how typical 50-Ohm and 75-Ohm Coax cable works too, but they're better shielded and have a better-defined characteristic impedance. (Ie, you can form a TEM wave in coax, but not so well in twisted pair).
So by twisting you are forming a more-isolated transmission line channel, which will reduce crosstalk between the other twisted pairs, not between the two wires in the pair, as they are ultimately tied together.
The unwanted signal (noise from interference for example) would be common on both conductors of a pair, so not opposite polarity, but yes you have the right idea.
The National Electrical Code requires that wiring in a plenum has a special teflon cladding that won't burn
PVC itself is fairly fire retardant, but it releases Hydrogen Chloride when heat is applied to it. Plenum rated cable burns, but it doesn't release HCl when it does so, and thus is required to be used in environments where air will be circulated.
If closing dors is a problem then I must assume that you live in a rental thatdoes not allow wiring to be pulled. Take a tri to your local home improvement store and look at what networking hardware is avaliable. For about US $100 I was able to pull 2 phone lines and 2 network drops to 3 bedrooms and the kitchen(8 new lines of both).
Then only special tool I required was a fishtape. I already had the utility knife, drill with 3/4" spade bit, and screwdriver.
The RJ-45 connectors that go into the wall do not require special tools to assemble. I still went to Radio Shack for patch cables. Home Depot charges 2x as much. I COULD have bought the connector tool and gone blind reciting "Orangewhite orange greenwhite blue bluewhite..." but the tool is almost US$50 for the cheep one!
Since I am only using 2 of the drops I pulled (now at least) Getting the tool to make my own patch cables is too expensive. If I get more than 3 network devices at the same time I will probably get the tool and break even vs premade cables. That would be 6 new cables of various length.
In any hoot, I'll have to upgrade way beyond my 4 port 10-base hub before that happens. The point is I'll be done, and never need to pull new cables again.
Oh, per my eletrician consultant leave about a foot of slack in the wall at each end so you can replace the ends several times when they go bad without pulling new wire.
Have fun!
Phil
Laugh, it's good for you!