I'm planning in using my web cam as a security cam at my front door and I was thinking in using a pc downstairs to see my web cam over the net, but I have keep both pcs running at the same time and the need of extra software as well, so i decided to use a Cat5 to run a Usb connection over at least 25', I've been searching a little over the web and I found a couple of ideas to connect Usb peripherals over Cat5 successfully and I went over the subject, but I realize that i didn't want to cut the cat5 and solder the usb connections to the cable, so I decide to build a couple of Usb dongles (female and male) to cat5 and the cool thing is that they can be used on existing Ethernet network wall connections as well. I know that I might be pushing the limits but it's worth the try.
I wouldn't use this devices for Data tho, I understand the there are plenty of connectors out there that have baluns (which I don't quite know how they work), to send and receive Data signal, so I wouldn't risk the try but for peripherals such as web cams, mouse or keyboard, and sound signals would do just fine (even S-video).
I would highly recommend using a powered Usb hub for the distance mentioned above, in regards of some of the limits for this type of configurations:
Usb limits are up to 15' (4.5 meters)
S-Video up to 50' (15' meters)
I got very useful information from Tony's Cafe blog, on distances limits and some other valuable info, you may want to take a look at his site: http://girasoli.org/?p=58
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Signing UpStep 1Materials and Instructions
Materials:
2 Ethernet Hubs (8pin RJ45 - salvaged from network cards)
1 Usb Male Plug Type A (any standard Usb cable)
1 Usb Female Plug Type A (from a Pc)
Solder Gun, wire and electric tape.
and of course a CAT5 Ethernet Cable
Instructions:
The hardest part was desoldering the Hubs from the salvaged PCB board, after that it was just a matter of selecting which cables of the CAT5 use to solder the Usb plugs and the RJ45 Hubs.
I select the pins in the following order:
RJ45 hub = USB plug
pin No. 2 = Green Cable
pin No. 4 = White Cable
pin No. 6 = Black Cable-Ground
pin No. 8 = Red Cable
I test the configuration at the other end and test the web cam (my work very well) later I isolate each soldered connection with electric tape (with yellow tape) and cover the hole thing (black tape), and voila!. 25' of video cable (plus the hubs) and working.
Easy and extremely cheap.
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This is all about timing. at 5 meters, the delay propagation in the cable is maximum 26 nS(Nano Seconds). This is the time the USB transceiver will wait after a packet transmission for an ACKnowledge answer.
So if your cable is longer, the ACK will be received too late, and the USB transceiver will be already in the timeout processus. It's for that reason that if you want longer cable, you need Active USB repeaters. These Active cables Are real relays that send ACK signals and re-transmit the data over another 5 Meters cable.
There is nothing about voltage drop or crosstalk here.
Once I ran RS232 over a 300 meters telephone cable! (max=16 m?)
It was working constantly for more than one year.
Sometimes we may test the "impossible" and it works.
1. On the RJ-45 8-pin jack, you want to avoid pins 1,2,3,6 because if it accidentally gets plugged into a switch or PC Ethernet jack, the 5-volts could fry something.
2. You want the power (+5v,ground) on the same color (blue,blue-stripe) so it doesn't make an electronic field that can ruin the valuable data lines. the phone company runs 24V to our homes on one twisted pair of wires and it works fine.
3. Twisting the two data lines on one color (brown,brown-stripe) will keep data integrity over a longer run of lines. Ethernet lines do that and it works just fine.
I suggest the following from the USB to the Cat-5 jack:
1. usb pin 1 (+5v,red) goes to RJ-45 pin 5 (blue-stripe)
2. usb pin 2 (d-,white) goes to RJ-45 pin 8 (brown)
3. usb pin 3 (d+,green) goes to RJ-45 pin 7 (brown-stripe)
4. usb pin 4 (ground,black) goes to RJ-45 pin 4 (blue)
Using this configuration, you could simultaneously run Ethernet to a hub AND your USB extension with splitters and all.
these are my observations:
usb power supply pins1 and 4 can supply with a steady 5 volts on both cat5 cables. cable 1 below 5 meters and cable 2 above 5 meters both registered on the tester 5 volts steadily.
while testing on terminal +data and -data i get a drop of .5 when i put the testers over 1x continuity.
this lead to a conclusion that signal from the usb running through a cat5 cable drops after 5m. but the 5v supply from the usb running through a cat5 is a steady power supply.
i made this project because i want to use my socket A old cpu as surveilance system of our home using usb webcams. i can connect up to 4 webcams but distributing it around the house is very tricky. im avoiding also of ip cams because of it's high costs any suggestions on how i might solve my problem? thanks for your ideas.
If your voltage didn't sag that far, then you have crosstalk issues. If this is the case, ground all the unused wires at the COMPUTER END ONLY (hook 'em to the black wire).
Seems the problem is not power (the hardware is powered) but data transmission (un-recognized by computer). Anyway, I used another solution (optic fiber).
Thanks
http://www.linksysbycisco.com/US/en/products/USB300M
lets try this:
Cat5 = USB Cable
White /Green = Green Cable
White /Brown = White Cable
White /Blue = Black Cable-Ground
White /Orange = Red Cable
Let me know if it works.
cheers
RJ45 hub = USB plug
pin No. 2 = Green Cable
pin No. 4 = White Cable
pin No. 6 = Black Cable-Ground
pin No. 8 = Red Cable
instead of using the pin numbering, select a specific color from the cat5, lets say green and white stripes to match the green from the USB cable, red and white stripes for the red in the USB and so on, make sure that the other end of your cable has the same scheme and I'll be fine; you can also try to use the cat5 cables as doubles, ie, combine 2 wires from the cat5 to match one of the USB, it will increase the flow of current from the USB port to the device.
cheers.