[VoIP] Channel Bank on Ebay [not mine] and E&M
Steph Kerman
stfkerman at jps.net
Fri Dec 7 23:19:56 CST 2007
I'll observe publicly that a few days ago I offered the 1997 edition of
Part 68, showing most all RJ definitions with descriptions and
schematics, complete with my bookmarks added to permit random access to
each RJ definition without scrolling sequentially through the document,
and with some pages rotated to facilitate on-screen viewing.
Despite all this discussion about what RJs are and are not, I've had one
request for the document. It was from someone who lurks quietly, and
based on my past observation, reads attentively.
I don't follow what you are describing. By "amp" do you mean 25-pair
AMP/Amphenol connector or amplifier? I don't know what a 66 style jack
is. There was an RJ20-series interface that was like a 12-line "series"
jack, with T&R in and T&R out for each of the 12 circuits. I think
that's the RJ-22 or perhaps 21. But it requires the insertion of a
jumper plug to restore continuity when the connectors are separated.
The apartment house door answering systems used in many cities use this
interface.
Steph
John Novack wrote:
> Correct.
> There were one or two added in later years. One I remember was a series
> configuration for units built in the 80's for ACD on 1A2, Dacon units
> were the ones I worked with, but there was at least one other brand.
> It was a multiple line RJ on a 66 style jack that when the Amp was
> removed it restored the line connections, but with the amp in place the
> T&R went through the ACD, along with A and A1. They provided a priority
> hold style indication with 400 cards. We used to joke they were really
> good at selling replacement 400 cards, flashing lights with the A lead.
> A 400 card had a much shorter life in a busy system.
> I may have seen one of those, usually we used the RJ 12 or 13 style, and
> installed them ourselves, rather than pay ( in those days ) C&P or Bell
> Atlantic rates for installation.
> Mid 1980s. By 1988-89 that market disappeared, as 1A2 rapidly
> disappeared as electronic systems improved.
> But we do ramble on. There is PLENTY of CORRECT information out there on
> Part 68 and Registered Jacks, and no matter how hard we try, we aren't
> going to get the current industry to use the correct terms, any more
> than the contributors to Asterisk coding will understand telephony and
> hybrid key/pbx concepts.
>
> The good news is, we don't need no RJ's in our systems
>
> RJ works the night shift, doesn't he?
>
> John Novack
>
>
> Steph Kerman wrote:
>
>> I think what John meant is that RJ codes refer to Registered Jacks.
>> Therefore a plug crimping tool by definition can not "do" *any* RJ
>> code. It can "do" plugs that mate with particular RJ codes but not "do"
>> the codes themselves as stated since the codes identify jacks.
>>
>> Perhaps this is a finer semantic distinction than some would care to
>> make but I believe it is what he meant and the point is valid since the
>> misstatement perpetuates or masks a misunderstanding of what the RJ
>> codes mean... that they identify a type of plug or jack the way "DB25"
>> does. They identify an electrical interface to the PSTN which has a
>> defined mechanical configuration more akin to the way RS-232 does. Just
>> as one would not say "RS-232 plug" referring to a DB25 or DE9, it's a
>> misnomer to use RJ codes to refer to the plugs and jacks.
>>
>> AFAIK, RJ10 is just another figment of someone's imagination. It's not
>> listed in my 1997 Code of Federal Regulations "FCC Part 68" document nor
>> in my 1980 Bell System Registration Service Manual. I've never heard of
>> it. I know of only one RJ definition that has been added and is not
>> shown there: RJ61 provides access to 4 CO lines on an 8 position jack.
>>
>> R12 and RJ13 provide access to a CO line terminating in a Bell System
>> 1A2 key telephone system. They provide access to the speech path along
>> with A leads (control leads towards the KTS to light the lights, stop
>> incoming ringing and clear a hold condition). One of them provides the
>> speech path access on the CO input side of the KTS CO line circuit. The
>> other provides it on the output (KTS telephone set side) of the KTS CO
>> line circuit. Part 68 will identify which is which. They all terminate
>> on a 6 position 4 or 6 contact modular jack with 4 contacts in use and
>> require a mating 6 pos 4 or 6 contact plug.
>>
>> There are no RJs associated with 4 position handset jacks. Likewise,
>> the jack on a telephone set by definition can not be an RJ though it may
>> have compatible contact assignments and mechanical characteristics. I
>> explained the reasons why this is so within the last 48 hours.
>>
>> Steph
>>
>> John Novack wrote:
>>
>>
>>> Repeating a previous post.
>>> Handset plugs and jacks HAVE NO RJ designation.
>>> All Rj designations refer to the wiring pattern and connections starting
>>> back in 1978.
>>> Refer to FCC Part 68 BEFORE 2000.
>>> Google should be your friend.
>>> RJ 12 and 13 reference connections to 1A2 key systems, RJ14 is 2 lines on one jack, RJ-25 is three lines on one 6 pin jack.
>>> RJ3x and 4x are 8 position modular .
>>>
>>> John Novack
>>>
>>>
>>> windmill wrote:
>>>
>>>
>>>
>>>> Steph,
>>>>
>>>> Perhaps you can clarify what RJ10 and RJ12 are, I had always thought the
>>>> RJ12 to be a telephone handset plug but I have never really known what
>>>> an RJ10 is. My Crimping pliers do RJ45 (8P8C), RJ11 (6P6C) and a 4P4C
>>>> connector which I believe is RJ12. I have seen a two pin version in this
>>>> same series used internally in some telephones, would that be RJ10?
>>>>
>>>> Brian
>>>>
>>>> Steph Kerman wrote:
>>>>
>>>>
>>>>
>>>>
>>>>> Thanks for the clarification.
>>>>>
>>>>> That has to be a moniker that someone invented, in other words, sort of
>>>>> a fiction. It has no real legitimacy no matter how many people may use
>>>>> it, the way RJ11 and most others do. Many people also refer to the
>>>>> handset jack as an RJ22, another mis-invention in this case since the
>>>>> RJ22 actually is a documented and defined interface that uses a 25 pair
>>>>> Amphenol mini-ribbon connector to connect to multiple lines.
>>>>>
>>>>> Regardless of its popular use, RJ has a formal meaning. It refers to a
>>>>> "registered jack" under the FCC program that was established to allow
>>>>> direct connection of privately owned equipment to the public network.
>>>>> Since the Bell System was never forced by the FCC to allow connection of
>>>>> privately owned equipment to their own phones at the handset interface
>>>>> (as opposed to directly to the line itself), no RJ was ever defined
>>>>> using the 4-position jack.
>>>>>
>>>>> Steph
>>>>>
>>>>> Mark Rudholm wrote:
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> RJ9 is the small (four conductor positions) connector
>>>>>> used on handsets and handset cords.
>>>>>>
>>>>>> (it's not normally used for phone lines, with some
>>>>>> weird exceptions, like Sangoma FXS PCI cards)
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
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>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>>
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>
>
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