Author Topic: Cable question  (Read 552 times)

Offline Mmg577

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Cable question
« on: April 21, 2017, 09:47:25 AM »
Hi- does anyone know what these cables are called and where I can get them? They are for use with a KX-T123211D.  Thanks!

Victor Laszlo

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Re: Cable question
« Reply #1 on: April 21, 2017, 11:20:24 AM »
Yes.

The cables are standard 25-pair, 24-gauge, double-ended key system cables, available in lots of places.

They are plugged into adapters made by AllenTel.  The industry name for these is "modular break-out adapters" or  "harmonica."

http://www.twacomm.com/catalog/model_AT2608.htm?sid=200EE1ECE71216BC0388F01F9A493396

"Modular adapter designed to provide a connection between 50-pin amphenol connector and 4, 6 or 8 conductor line cords. Consists of either male or female 50-pin amphenol connector and 6, 8 or 12 modular jacks. Each jack is clearly marked to identify its associated line circuit. Equipped with VELCRO brand touch fastener to insure [sic] a secure connection."

Other companies make them, such as Suttle and Ortronics.  There are some on Ebay right now, cheap. Search for "modular adapter."
« Last Edit: April 21, 2017, 11:46:36 AM by Victor Laszlo »

unbeldi

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Re: Cable question
« Reply #2 on: April 21, 2017, 11:45:26 AM »
I don't recall them being advertised specifically for the Panasonic systems, but it does seem plausible that they were available.
Basically, they are standard 25-pair telco cable with Amphenol connectors on each end.  At one end, the Amphenol connector is fitted with a multi-jack break-out adapter.  See here for examples of those:  http://www.classicrotaryphones.com/forum/index.php?topic=13566.0  These were made by many firms, a notable one perhaps is Ortronics.  I once acquired a bunch of those pictured. It has 12 four-pin RJ-11/14 jacks.

Specific equipment manufacturers may have sold specifically configured cables, for example, just with the proper number of twisted pairs that one of their cards support.  Usually those are very expensive, and it might be better to acquire generic materials.

Most often, when installing a PBX like the 1232s one would use a 66-type or 110-type punch-down block in a closet where the inside wiring terminates, instead of multi-jack modular adapters, but these certainly can be very convenient.

Victor Laszlo

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Re: Cable question
« Reply #3 on: April 21, 2017, 11:57:16 AM »
Seems to be an echo in here.

unbeldi

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Re: Cable question
« Reply #4 on: April 21, 2017, 12:16:06 PM »
Seems to be an echo in here.

Can you hear me now ?

Offline Jim S.

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Re: Cable question
« Reply #5 on: April 21, 2017, 01:06:15 PM »
I have some spare modular breakouts, and I even know where they are. I would consider selling some. PM me if interested.
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Offline Mmg577

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Re: Cable question
« Reply #6 on: April 21, 2017, 02:12:54 PM »
I currently have a Panasonic 824 and getting a KX-T123211d.  The 824 is setup as pictured, so I figured the modular breakout option would be best for me.  I have lots of old phones, just not very good at getting them setup.  ;)

Victor Laszlo

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Re: Cable question
« Reply #7 on: April 21, 2017, 04:14:09 PM »
Does the new one have modular inputs/outputs or does it have an amphenol connector?

Offline Mmg577

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Re: Cable question
« Reply #8 on: April 21, 2017, 04:38:16 PM »
Here is a pic of the new one. 

unbeldi

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Re: Cable question
« Reply #9 on: April 22, 2017, 09:31:16 AM »
Since the expansion cards of the 1232-systems have only eight station ports each, but the Amphenol connector has 50 pins for 25 pairs, roughly only one third of it is used, and when using standard 25-pair telco cable, much of that would be unused too.  For this reason, I have seen special cables sold by equipment manufacturers that exactly matched the capacity of their equipment.  But in the aftermarket, such specially configured cable is often hard to find.  Using standard cable turns out to be cheaper.  However, this does not apply to the fan-out connectors.   The Allen-Tel connectors linked to earlier cost an astonishing $42, per that listing.  I know they can be found cheaper, last night I quickly scanned eBay and found some for around $10, having eight modular jacks with eight contacts each (8P8C), often erroneously called RJ45.    Even those 12-jack units that I showed have multiple pairs per jack, two in that case.   So, if used for connecting the PBX via modular connectors, you still need to split the two or more lines per jack, unless you have two-line phones.   So, that requires even more adapters.  Multi-jack adapters with single pair RJ11 jacks for only eight ports are not easy to find.  I didn't see any on eBay last night.

I think a better solution perhaps is this.  I did see a few of these Allen-Tel  AT125-SM  25-jack panels, as shown in my picture (one of mine).
These break out all 25 pairs of a standard telco cable into single-line RJ11 jacks.  They have a female and a male 25-pair Amphenol connector wired in parallel, so either a male or a female cable end of a standard telco cable can be used.   The other end of that cable I would modify by splitting the 25-pairs into three groups of eight, leave the first group on the existing connector, and cut the two other groups off and fit them with new connectors, so that they can be connected to two additional expansion boards in the PBX.  But telco cable can also be bought with just one end terminated into a connector, either female or male, so the other end does not have to be cut.  I also have cut cords in half, that had connectors on each end, to yield two single-terminated cables.

At the cost of the work involved fitting the connectors, it saves cost of additional cables, and additional modular fan-out connectors. As a result you have only one neat cable, and only one 25-pair jack panel that can be neatly mounted on the wall next to the PBX, or anywhere in the house for that matter.  These panels are very convenient, and don't usually cost anything more than the cord-end adapters.  I have bought them for less than $20 ea on occasions.

50-pin D-shape Amphenol connectors can be bought at electronics supply companies.  Not all have solder contacts, some can also be press-fitted.

« Last Edit: April 22, 2017, 09:37:13 AM by unbeldi »

Offline poplar1

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Re: Cable question
« Reply #10 on: April 22, 2017, 09:56:46 AM »
It is true that only one pair per station, and 8 pairs per card, are needed for single line phones. However, it is not the first 8 pairs of each 25-pair connector. Rather, there are 3 pairs per station so that proprietary phones can be used. For single lines, you would need to connect to pairs 1, 4, 7, 10, 13, 16, 19, and 22 of the connector on the circuit pack.

Rather than install or reconfigure 25-pair plugs, you might want to use a factory-made single-ended 25-pair cable for each card and terminate (punch down) the pairs of the other end of each cable on a patch panel.

https://www.manualslib.com/manual/535320/Panasonic-Easa-Phone-Kx-T123211d.html?page=11#manual
« Last Edit: April 22, 2017, 10:05:34 AM by poplar1 »
"C'est pas une restauration, c'est une rénovation."--François Martin.

unbeldi

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Re: Cable question
« Reply #11 on: April 22, 2017, 10:18:06 AM »
I think a lesson from evaluating the wiring options for these medium density PBX solutions, is that it can be expensive to wire them.   The smaller systems, with up to perhaps 24 ports, e.g. the KX-T308, 616, 824,  are still small enough that they are equipped with RJ11 jacks right in the unit, and it is very cheap and trivial to connect telephone equipment to them.  With larger system, such as the KX-T1232.. systems, while they can be used in small configurations, they require higher density wiring methods which are more expensive and technically more complex.

I also have several 308 and 616 systems, and the simplicity of them is marvelous.  Connecting a collection of telephones to them, is essentially a near zero-cost aspect.  I used to keep a unit under/by every shelf of display phones, with a single trunk cord running to a central switch to route calls between them.   But I also have higher density channel banks, with 24 ports (Adtran), feeding from a T1 line, and 40-port digital channel banks (Carrier Access ADIT) running MGCP protocol over Ethernet to my Asterisk C-Net tandem.  For these I am using the Allen-Tel 25-pair panels.

When it comes to even higher density, the cost per port is better again, as the bigger equipment is much more cost-effective on a per port basis.
Shown here is a Western Electric 88AW1-300 wiring block that I picked up for $20 in a lucky purchase.  It has room for 300 telephone lines, which have to be connected to the 110-style punch-down block.


unbeldi

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Re: Cable question
« Reply #12 on: April 22, 2017, 10:19:39 AM »
It is true that only one pair per station, and 8 pairs per card, are needed for single line phones. However, it is not the first 8 pairs of each 25-pair connector. Rather, there are 3 pairs per station so that proprietary phones can be used. For single lines, you would need to connect to pairs 1, 4, 7, 10, 13, 16, 19, and 22 of the connector on the circuit pack.

Rather than install or reconfigure 25-pair plugs, you might want to use a factory-made single-ended 25-pair cable for each card and terminate (punch down) the pairs of the other end of each cable on a patch panel.

https://www.manualslib.com/manual/535320/Panasonic-Easa-Phone-Kx-T123211d.html?page=11#manual

Ah, yes.  Good point.  Using the single-terminated cables is the cleanest solution.
Only 2 pairs are needed for the proprietary phones, though, but they are wiring them in sets of 3, so that they can be used with standard 8 x 6P6C modular break-out connectors.
« Last Edit: April 22, 2017, 10:27:09 AM by unbeldi »

Offline poplar1

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Re: Cable question
« Reply #13 on: April 22, 2017, 11:18:02 AM »
3 pairs are required for KX-T123235 proprietary phone only.

It is easy to connect a phone collection display to a KSU with individual line and station ports, where the phones are close by. In a large office environment, the lines are usually installed by the phone co. on RJ21-X, and the 4-pair station wires are terminated on 110 or 66 blocks. Thus, there has to be a way to cross-connect the outside lines to the KSU, and also the station wires to the KSU. Often, I have seen techs make their own 1- or 2-pair cross-connects using jumper wire and installing a modular plug on the KSU end and punching down the other end on a 66- or 110-block. (For Comdial KSUs, this was usually just for the lines, which had RJ14s for each 2 lines on the side of the KSU. The Comdial stations had a 25-pair connections to the KSU). Our boss would never order the proper modular plugs for solid wire, so the techs would use the available plugs that are designed for stranded wire. I would usually mount several RJ14s near the KSU, and cross-connect 2 lines per RJ14 to the hangoff block from the RJ-21X.

AT&T stocked various lengths of Brand-Rex  4-pair station wire with plugs on each end. Perhaps this was intended for customer installation or moves of Merlin sets or MET Sets.
"C'est pas une restauration, c'est une rénovation."--François Martin.

Offline Jim S.

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Re: Cable question
« Reply #14 on: April 22, 2017, 11:21:55 AM »
I used to  have  a 616 with 25' line cords from the ports to the telephones.  It worked well in that phone room. I was able to route the cords out of the way. I have bought 50' and 100'  modular line cords as well.

Just another option.
Jim S.


If I am hooking up hardwire phones I wire a modular surface jack to the line cord. This is an easy way to make hardwire sets modular.
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