[RFI] Ethernet RFI and connector wiring

Alan NV8A (ex. AB2OS) nv8a at att.net
Thu Jan 27 14:59:12 EST 2005

1. I have discovered that this is a recognized wiring sequence, the 
result being a "rolled" cable, whose purpose I cannot discover.

See: http://www.cisco.com/warp/public/701/14.html#topic8

2. I discovered how to take the sockets apart and interchange the green 
and white/green conductors instead of cutting off the plugs and 
installing new ones.

3. Unfortunately, changing the connections does not seem to have reduced 
the RFI.

Alan NV8A

On 01/25/05 11:04 am I wrote:

> OK, I have found something very strange about all these "Ethernet RF 
> Filters" I bought from the local computer store (3 turns of CAT5 cable 
> thru a toroid of unknown composition and shrinkwrapped, with an RJ45 
> male on one end, RJ45 female on the other):
> The conductors are connected to the socket (marked "T&B," which I assume 
> is "Thomas & Betts," a well-known and reputable manufacturer) according 
> to the color-coding and numbering on the socket, but the color-coding 
> and numbering are weird:
> 1 Orange/White
> 2 Orange
> 6 Green
> 4 Blue
> 5 Blue/White
> 3 Green/White
> 7 Brown/White
> 8 Brown
> IOW, pins 3 and 6 are interchanged at the socket end, while the 
> conductors at the plug end are connected in the normal sequence.
> Where on earth did this wiring sequence spring from?
> It looks as though the only thing I can do if I want to keep using these 
> things is cut off the plugs and install new ones with weird wiring to 
> match the weird wiring at the socket end.

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