[sci.electronics] Pinouts of Modular Connectors

scott@eddie.MIT.EDU (Scott Statton) (09/24/88)

Netlanders:
   I submit this definition of the wiring of RJ-11, RJ-18, and RJ-14 devices,
as specified at 'the horses mouth'.

Quoting from
 Title 47 CFR, Chapter I (October, 1986) [Federal Communication Commision]
 Section 68.502, "Configurations"

[begin quote]

USOC RJ-11 -- Bridged T/R; 6 position jack.
 Single Line Bridged tip and ring only -- conductors
 1, 2, 5, and 6 are reserved for telephone company use.  RJ-11W for wallmount,
 RJ-11C for all others.

	pinout
	1 -- reserved
	2 -- reserved
 	3 -- RING
	4 -- TIP
	5 -- reserved
	6 -- reserved

USOC RJ-18 -- Bridged T/R with make-busy arrangement; 6 position jack.
 Single line bridged tip and ring only with MB/MB1 leads.  Conductors 2 and 5
 are reserved for telephone company use.  RJ-18W for wall mount, RJ-18C for all
 others.

	pinout
	1 -- MB
	2 -- reserved
	3 -- RING
	4 -- TIP
	5 -- reserved
	6 -- MB1	note:  when MB and MB1 are shorted, the line
				will show as artificially busy.

USOC RJ-14 -- Two-line configuration Bridged T/R; 6 position jack.
 Two line bridged tip and ring.  RJ-14W for wall mount, RJ-14C for all others.

	pinout
	1 -- reserved
	2 -- TIP 2
	3 -- RING 1
	4 -- TIP 1
	5 -- RING 2
	6 -- reserved

[end of unauthorized quote]

Note that the CFR goes on to describe several other connectors that are not
 related to this discussion.  I will not insult the net with a poorly drawn
 ASCII graphic showing the connectors physical layout -- look at a modular 
 plug for youself.  The pins are numbered from left to right, 1 through 6.
 NB -- on many cordsets for residential installation, contacts for pins 1 and 
 6 are missing for economy.  On a smaller proportion, pins 1, 2, 5, and 6 are 
 missing.

Note also, that the CFR describes A/A1 signalling, where pins 2 and 5 are used
 to signal PBX systems for two purposes.  One:  That the given extension is
 in use, two: to signal that the given conversation is to be placed on 'hold'.
 It neglects to mention the pinout of the RJ-12 and RJ-13 jacks used for 
 this system.  * sigh *.
-- 
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scott@eddie.mit.edu                | I don't have any opinions.
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