SPONSORED LINKS
Hmm, thought this would have the cross-over question answered - but it doesn't... From: jagosta@interaccess.com (John Agosta) Subject: RJx, USOC, and Jack Types Date: 11 Jul 1997 01:27:31 GMT Organization: Agosta and Associates Recently, there have been a few questions about RJxx jacks, pin-outs, and such. Here is a little something that may help out; it is (almost) 'verbatim' from the Siemen Company's catalog which contains some very good information on wiring guidelines. \ There are 4 basic modular jack styles. The 8 position and 8 position / keyed modular jacks are commonly and incorrectly referred to as RJ45 and keyed RJ45, respectively. The 6 position jack is commonly referred to as RJ11. Using these terms can sometimes lead to confusion since the RJ designations actually refer to very specific wiring configurations called USOC (Universal Service Ordering Codes). Each of these jacks can be wired for different configurations. Looking into the female connector, with 'clip' at bottom, the wiring is as follows: 6 Position jacks: 1 2 3 4 5 6 T/R Pair Pin # T 1 4 R 1 3 T 2 2 R 2 5 T 3 1 R 3 6 RJ11 is a 1 pair jack. RJ11C is a two pair jack. RJ25C is all three pairs. DEC's modified 6 position jack has an 'offset' key structure and is called MMJ. The offset was intended to prevent accidentally plugging DEC terminal equipment into analog lines and vice versa. Wiring is as follows: T/R Pair Pin # T1 1 3 R1 1 2 T2 2 4 R2 2 5 T3 3 1 R3 3 6 8 position USOC jacks can be wired for RJ45S, RJ46S, and RJ47S. Pin and pair placements are as follows: 1 2 3 4 5 6 7 8 T/R Pair Pin # T1 1 5 R1 1 4 T2 2 3 R2 2 6 T3 3 2 R3 3 7 T4 4 1 R4 4 8 (Specific wiring for USOC configurations, with common applications can be found at www.ameritech.com) T568A Jacks: 1 2 3 4 5 6 7 8 T/R Pair Pin # T1 1 5 R1 1 4 T2 2 3 R2 2 6 T3 3 1 R3 3 2 T4 4 7 R4 4 8 T568B Jacks: 1 2 3 4 5 6 7 8 T/R Pair Pin # T1 1 5 R1 1 4 T2 2 1 R2 2 2 T3 3 3 R3 3 6 T4 4 7 R4 4 8 (Pairs 2 and 3 are reversed from T568A) Other jacks include: 10Base-T T/R Pair Pin # T1 1 1 R1 1 2 T2 2 3 R2 2 6 Token Ring T/R Pair Pin # T1 1 5 R1 1 4 T2 2 3 R2 2 6 ANSI TP-PMD X3T9.5 T/R Pair Pin # T1 1 1 R1 1 2 T2 2 7 R2 2 8 Colors: UTP 24 AWG stranded patch cable starting with pair 1: Green / Red, Black / Yellow, Blue / Orange, Brown / White. UTP solid 24 AWG horizontal cable starting with pair 1: White / Blue, White / Orange, White / Green, White / Brown. Ciao, Tom _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ FROM:Tom Trottier, MBA Senior Technical Architect SHL Systemhouse Ltd. Ottawa Global Development Centre 50 O'Connor St. Suite 501, Ottawa K1P 6L2 Canada +1 613 236-6604x5539 fax 232-5182 ttrottier@shl.com ---------- From: Geovanny M. Ortiz[SMTP:o-n-a@shadow.net] Sent: 1997 July 13 - Sunday 11:31 To: Thinkpad Mailing List Subject: Home network Some time ago I posted a message about a coax home network. Some of you responded with very good solutions, one of which was to buy a crossover twisted pair cable. I've tried to locate one locally, but had no luck. Some of you also mentioned that it was very easy to build one. What would I need to build one? Thank you all in advance for your answers. Geovanny M. Ortiz