Question on phone cord connectors

The RJ series of jacks and plugs are for a Network Interface. Handset cords and other station set equipment are left to the equipment vendors to put on their nomenclature. The Standards bodies may have worked up a "standard" ID for handset cords by now, but I haven't seen it.

Google "telephone handset cord"

Mostly RJ10

Where does the "RJ10" code come from?

is a good a point as any to start from (Usual caution to check anything on wikipedia against authoritative sources). RJ10 is *NOT* an official standard or the proper name for the connector as you indicated above, but if the OP just wants to buy a couple of plugs and a crimping tool to repair his phone its the perfect Google search term.

As to who invented the terms RJ9, RJ10 and RJ22, and when, well your guess is as good as and probably better than mine. Back in '95 Maplin electronics were selling them as 'FCC68 Modular Plug 4C4P' so it wasn't common usage in the UK in the mid 90's In '86 they didn't stock them at all. Sorry thats not a lot to go on, but I have better things to do than dig through dusty parts catalogs.

Thanks for the link. It's better than some.

FWIW RJ does not mean Registered Jack; it means Registration Jack. An RJ is used for Network Interfaces for services provided under the FCC mandate for registration of customer terminal equipment.

I began working on Standards in 1986. In addition to the technical standards, the industry via ANSI and Telecommunications Committee T1, began working on a NI connector catalog to clarify the multitude of uses of off-the-shelf plugs and jacks. As you know, the RJ information defines the connector type (for example a 4-pin mini-modular) and the pin assignments and designation of the leads crossing the interface (for example pin 2 = T and pin 3 = R. pin 1 and 4 not used).

I believe it was around 1990, we started to define connectors in common use that were not part of the Registration Program. Since these were typically equipment interfaces (such as a handset interface to a telephone or an NT1 to a NT2) much of the work was passed to the TIA standards group (now ANSI TIA). As a result there should now be Standard Jack Assignments (SJA) defined by Committee T1 and harmonized with TIA, and others issued by TIA. I left in 1994 so I lost track of it. The non-SJA nomenclature would permit manufacturers to sell the same physical jack used as a Network Interface without calling it one.

I got only three relevant Google hits for SJA connectors.

Wikipedia says that it's commonly referred to as an RJ9, RJ10, or RJ22, but it also says that those names are incorrect. (I think the deal is that it's only officially an RJ-series connector if it's part of the standardized telephone system, and the handset connectors are completely up to the whim of the manufacturer, even though there is a de facto standard.)

I added a crosspost to comp.dcom.telecom.tech; maybe someone there knows.

The most correct name for the handset connector is a 4p4c modular plug/jack.

Just like a phone line connector is a 6p2c modular jack (or 6p4c sometimes).

And an Ethernet jack is an 8p8c modular jack.

ie. x position, y connector.

I've seen 10way connectors the same width as 8 way ethernet ones ones (the three I've seen were on bar-code reader cables)

would that be 8P10C or is there a special designation for under-width connectors?

Bye. Jasen

three

No. How can you have eight positions, and ten contacts? A 'position' is a place for one contact.

No, it would be 10p10c modular connectors.

They can be a touch wider than 8p8c jacks as well, but not enough to account for the "extra" 2 connector pins.

three

the plug is the same width as that used for twisted pair ethernet, what is commonly called "RJ45" or 8P8C, but it has 10 contacts.

Bye. Jasen

plug/jack.

sometimes).

three

The width of the housing has nothing to do with the designation. It could be three feet wide, and still only have ten postions.