atcomsystems.ca/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Greetings and a Request for Some Info on How to Setup Small Keyset System

Hello to all!

My name is Aris, and I am three months into a vocational degree in Installation and Repair of Telecommunication Equipment (phew, what a title!) in Montreal, Canada.

I hold another vocational degree in Networking and Internet Security, and worked for several years in the field, mostly as a support technician. I voted out of IT, because of the jobs lack of a "hands-on" aspect. I much prefer working with hardware then dealing with annoyingly repetative software issues.

I would like to apologise in advance for asking what I'm sure has been answered several dozen times already in these forums.

I am the proud owner of two lovely rotary 564 keyset telephones that I would like to get up and running for no practical purpose at all, just for what I consider to be the fun of it.

From what I understand, I will be needing a KSU and two 400d cards for the KSU, but I am really at a loss as to which KSU I would need, and how to set it up.

I'm already familiar with industrial Cat 3 cable, and its colour code, I know about my rings and tips, and I have a solid understanding of electronic fundamentals.

Any help would be much appreciated

Thanks!

Cheapest way to go would probably be a 551 KSU with a ring generator. You'll also need some 25 pair cable with a female amp/champ connector. If only one line you really wouldn't need the ring generator.


To the board, enjoy.

Bill is definitely right here, Aris. The 551 KSU is compact and simple to wire, readily available and any kind of 400 line card (A-F) will suffice for your application.

Thanks for the prompt reply and warm welcome Bill and Ed! I'll see if I can locate a 551 KSU somewhere online. I know of this place in Texas that sells vintage equipment.

Bill, when you say amp/champ connector, are you referring to an amphenol connector?

Thanks!

PM sent regarding KSU purchase/availability.

Bwahahahahaha, we caught another one! Welcome home, Aris. You're gonna love this place! John C.

Welcome to the exciting world of 25-pair cabling. I just sold a 551 on the E place for a low price. They are out there. I have 45 years' experience with 1A2 systems, so ask away.

Thanks to all for the warm welcomes

Arthur, unfortunately I don't think I'll be seeing to much 25-pair cabling in my future career Everything is Cat 5e and up now, for commercial anyway.

But, judging from my IT experience, there are still quite a few vintage (or "legacy" as we say in IT), systems out there, and I would very much like to become acquainted with the 1A2 system, since I would like to be the tech they call when everyone else is staring in bewilderment!

Cat 6, IF you learn 1A2 you learn the basics of telephony, the granddad of your IT world.

Even 1A2 will never be "Legacy" equipment...it will work until the bitter end versus an every day reboot for IT equipment. If IT equipment weren't so fragile and needed these restarts, you would not have a job.

Now that that is cleared up, IF you can't find a WECO 551 (danged old Bell guys) try a great KSU, ITT 601. With a little imagination and knowledge it will do 5 COs and an intercom.

Bye the way, did I mention I was a danged old Bell guy and welcome to the BB?
Keep your sense of humor and smile....hang on for the ride of your life .

KLD, I couldn't agree more, that the 1A2's still in operation will work till the bitter end. In my humble opinion, pretty much anything made after 1990 is borderline crap (there are exceptions of course).

I drive an 88' Saab, with only 107KKM on the odometer, in CANADA! She hasn't let me down yet! (OK, she needs some TLC every now and then, but overall the car is a rock).

As far as IT equipment, in most cases it's not really the hardware that's a problem. You stick a LINUX OS in 600$ DEll desktop, and it will last forever. Problem is LINUX is not exactly user friendly, it actually demands that you know how computers work to a certain extent (kind of like the 1A2 eh?), but in our McWorld, there are very few who will make the effort (myself included , my loss completely, since one can make a pretty penny knowing LINUX well).

Before I knew anything about telephony, I didn't realise the significance of a 4 pair UTP ethernet cable. I was just amazed to find out that it's nothing more then the first 4 pairs of a 25 pair set: BW/B, OW/O, GW/G, BRW/BR!

The entire modern world, running on a technology that stretches back to the day of Mrs. Mckinnley patching you through on her switchboard.

Mind boggling!

:toast:

It looks like you may have found a home here....

I, too, am a huge fan (from a nostalgia/cool factor standpoint) of the 1A2 systems, and an even bigger fan of the people who understand them!

About ten years ago I worked briefly with a guy who had served time with bell in the Atlanta area. I drooled over his neatly ring-bound and organized collection of Bell System Practices. There was some incredibly awsome stuff out there back in the day.

About as far back as I can go is the early 80s. I'm just now finally letting go of my Northern Telecom SL-1, because I really want caller ID. That system was intimidating at first, but it all makes sense when you take the time to learn it. On the other hand, I'm baffled by the mechanics of the 1A2 systems, and I have an incredible amount of respect for the people who had to master that stuff.

Well you came to the right place. Our resident professional collector and guru of the "real stuff" (Arthur P. Bloom) has a collection of equipment that will make your head spin.

I was wondering if anyone knows of a website that provides a decent run-down of the 1A2?

Kind of like, "1A2 For Dummies" type of place?

[Cat 6, reminiscing of the days when things were built to last G*d damn it!!!]

Lee's ABC of the Telephone had a volume on 1A2. Not sure if it's still available.

Sam

Thanks for the reply SS!

There seems to be multiple volumes. Was there one specific book on 1A2?

The bell system had a 3 book set. I think you can still find them, but they aren't cheap.

Here\'s one source.

Holy ****!!! You weren't kidding when you said they weren't cheap! That's a little out of my price range, besides, I found an "ABC to Telephones" on Abebooks for a reasonable price.

Thanks for the link though!

You might be able to find them cheaper, I've never tried. Got the first two volumes, lost the 3rd someplace.

Lee's ABC's books addressed the private-labeled brands, like ITT and Stromberg-Carlson (Comdial). Western Electric products were still taboo at the time, so there's not much information about it in the Lee's books.

Of course, 1A2 is pretty much universal with regard to operation/wiring between brands but many of the specialty items, like intercoms and exclusion were handled differently.

Taken from Wikipedia:

"Each of the keyset cables was usually run back to the wiring closet, or whatever central location where the KSU had been installed, and terminated on a connection device known as a 66 block or punch block. The blocks most often used to terminate these station cables were the type 66M1-50. Each of these blocks could accept two 25-pair cables (50 pairs, total) for termination.

Cross-connect wire jumpers, consisting of three twisted pairs (the six wires referenced above) would then be run between these blocks and the larger distribution connecting blocks within the KSU."

Could anyone tell me a little about this?

This may be a completely stupid question, but since I'm only hooking up two lines (red/green, yellow/black), would I need a 66-Block?

If I'm understanding correctly, I punch my two live pairs into some block (could make a little one myself), and then run jumper wires for the two lines from the punch block to the internal block in the KSU?

Sorry, I don't think I'm making much sense (it's 5 a.m.!), oK, so is this how it works:

The actual 564 amp connectors terminate either directly on the KSU, or via an extension cable? And then I would need to run jumper wires from the KSU's block to another block which will contain my terminated home lines?

Sorry about all the questions!

Another quick question:

The buzzer inside my Northern Telecom 564 is not actually terminated to anything within the phone. The two blue wires have their ends crimped, and are just hanging around.

Where do I hook these up?

Ahhh, the fun of 1A2....

This is a long process but here is the short version:

A 25 pair cable runs from the site of the telephone (this has an amp connector at the telephone end) back to a central location and is "punched" onto a block such as a 66M1-50.
There are "punch blocks" within the KSU. The "cross connect" wiring connects the KSU blocks to the 66 blocks that have the telephone cables attached. Thereby the name "cross connect field".

As for the CO feeder, it goes onto the KSU punch block to feed the DT to the KSU...through the KTUs, and out to the KSU punch blocks to the telephone punch blocks then through the 25 pair cable to the amp connector to the telephone cable tail into the telephone.

As for the buzzer leads...I am not familiar with NT 564 but most 564 have pairs "spared out" for the attachment of the buzzer leads. They go where they need to depending on the use...intercom, common audible, or direct line buzzer.

You really need to learn the basics here before jumping into the optional features.

Have a good time....

You can just hook up the tip and ring and get dial tone and have it function as a plain old phone. You wouldn't have lamps, hold, common ringer or be able to add any other functions without the KSU and a 25pr cable. What good with that be?

I really can't afford to buy a shop manual, so thanks for any help you can give me, since you know a little about Saabs. I'm only going to be driving my Saab in one direction, and at a fixed speed of 35 MPH. Can I disconnect the steering wheel and just weld the steering components together? Can I weld the shifter in 3rd gear and just leave it like that?

Seriously, I have been working on 1A2 systems (and 1A and 1A1 systems before that) for 40 something years. I have assisted many workers and enthusiasts in setting up and enjoying thse old systems. Feel free to contact me privately if you would like to understand the big picture. I have most of the documents that you would need to immerse yourself in 1A2. You might also want to join the TCI which has lots of members who dabble in 1A2, and switching systems.

See, Aris, I told you there is more experience here than hamburgers sold at Wendy's!!!

Thanks, Arthur.

I can most definitely see that Ken! It looks like I'll have my little hobby 1A2 up and running in no time!

Currently in the process of re-soldering the RJ-21 connector back to my NT 564. Slight pain in the butt.

Quick question:

I am trying to solder the amp connector back onto my 564. Is pin 1 ring, and pin 26 tip, or the other way around? KLD kindly provided me with a run-down of the wiring sequence, but I'm not sure of what I mentioned above.

Thanks!

Cat 6 -

26 is Tip (W/Blue)
1 is Ring (Blue/W)
27 is Tip (W/Orange)
2 is Ring (Or/W)

etc.

Sam

Be a heck of a lot easier to replace the cord, no?

Aw, come one, Arthur, some of us enjoy the aroma of hot solder!

Thanks SilverSam, but I think I might take Arthur's advice. Despite enjoying the smell of hot solder, I'm not too happy about all that lead going up my nose.

It's not lead, it's fumes from the flux. More than ten years of breathing it back in the 60's and 70's has only made me a better person.

-Hal

....and less hair growing in his nose...... :rofl:

LOL KLD

But, hbiss, don't the fumes contain lead? I thought that's what the whole fuss over soldering was these days, and why they are coming out with lead-free solder.

In any event, I ordered a Cat 3 male/loose amphenol connector cable, but come to think of it, I really don't know how much less trouble it will be as Arthur seems to think.

After all, there are a hell of a lot of ends to screw in on the phone end, but then again, my soldering skills leave something to be desired, so even if I do solder my amp connector back on, there's no guarantee it will work properly.

cat 6 if you ever need parts for those old phones PM me for my supplier, they rebuild mostly norstar but can get certain old parts. im over on the south shore

Will do SE. Merci bien!

Now that I've thoroughly inspected the interior wiring of my Northern 564, I'm a little disappointed in the craftsmanship All the lamp grounds run back to the lamp ground for line one, that's why there are shorts on the amp connector leading from pin 3/28 tip to the rest of the lamp grounds.

That's a little cheap in my opinion. So it's a good thing that I ordered the cable, because now I can give each lamp the grounding they deserve!

But, hbiss, don't the fumes contain lead? I thought that's what the whole fuss over soldering was these days, and why they are coming out with lead-free solder.

You don't heat it enough to vaporize it. The fuss is to keep lead out of landfills and the environment when electronic devices are discarded. The "fuss" is not because of this country by the way, ROHS is a European program but because we manufacture for the world market we have to comply with it.

I never thought the U.S. had initiated the "fuss", and I don't think I implied it. Even if it were an American policy, more power to you. I think it's a good policy. Excessive lead levels makes people a little bonkers, or just kills them! Fall of the Roman Empire and all that. Sorry for any misunderstanding.

Didn't think you implied anything. Just pointing out where it originated. It is a good policy. We here in the states have been banning lead in plumbing since I think 1994. Lead-free solder for everything soldered on potable water and waste lines. Brass fittings and plumbing items like faucets containing lead are banned.

Now we only get lead in our bodies from whatever the Chinese send us.

-Hal

Cat 6, if you run a ground to each lamp you now have a 565...not a 564. The lamp ground common is so the spare pairs can be used for other things ... like making a ten button set work on a 25 pair cable (three pair per line, eight lines plus hold and ICM = 10 buttons).

I solder a ton of audio cables and I don't think I have gone crazy (yet)!

What the Chinese send us...which has become pretty much everything! (sigh)

565 eh? Great! An upgrade!

No, actually a downgrade. At least that is the way I would see it. I believe the 565 was released to replace the dying and 'old fashioned' phones on systems that were originally installed with individual lamp grounds and A leads.
As for sodder, ever'body knows that ever'thing 'eelectronical' runs on smoke. When the smoke gets out thru a hole, the dang thing quits. All them reepare guys do iz blow sigareet smoke back in da hole and sodder it shut! John C.

But according to KLD, it was the 565 that had the individual lamp grounds. My 564 had one lamp ground for all 6 lamps.

Anyhow, I just finished wiring the new amp connector cable to the phone. I wired it in 565 format, with an individual ground for each lamp.

Easier then soldering the old amp connector back on!? Uhhhh....no, definetly a no on that one. It was borderline neuro-surgery.

Oops! Just realised the spelling mistake on my signature line!

It took an especially long time because I did not crimp the ends. I wrapped the stripped wire around each individual screw.

I'm sure it would have been much easier if I had stuck a fork head crimp on each wire tip, but I don't know how to crimp 24 AWG wire, nor do I have the tools.

Never mind how to get it done, try to find some 'fork head crimps'. I assume you are referring to what we call spade lugs. Those small ones are TOUGH to find. Haven't looked for them in 10 years, and they were scarcer than a clean teenagers room then! John C.

It's done already. Now I'm just waiting for my KSU, and I'm in business.

There's nothing wrong with your lamp grounds being tied together in the set as long as you maintain proper polarity. I swear that your KSU and cable are on the way. I am surprised you haven't received them yet.

Okay, you woke me up.....565 came first .... 564 was an upgrade.....either way will work UNLESS you need the extra pairs....look at a print on the 10 button set to see what I mean.

Now let's confuse the situation....WECO 851 AIM.

Well, sort of...

Actually, it's two and a half pairs per line key, of which there are 9, whether they are used for CO/PBX or ICM service.

(The unused "balance" leads of line keys 2, 3, 4 & 5, generally left insulated and stored in a 56X-series phone, are used as the "A" leads for line keys 9, 8, 7 & 6, respectively.)

So, counting the conductors, we have:

T,R,A,LG,L times 9 keys is 45 conductors.

A1 ground = (Orange/White) = 1 conductor

Ringer pair (Yellow/Slate) = 1 pair = 2 conductors

Buzzer pair (Yellow/Orange)= 1 pair = 2 conductors

Total conductors = 50

In a Western 2830 set, the lamp grounds for line keys 1 through 7 are dedicated to mounting cord conductors. (In ITT sets, I seem to recall that the lamp grounds were "bunched" on terminal screws, allowing them to be separated and used for other applications.) The last two lamp pairs (LG & L leads for line keys 8 & 9) and their associated mounting cord leads are connected on terminal screws inside the set, so that they can be moved and used to provide the four leads needed for 3-type speakerphone service, (T1, R1, 1T & 1R) in the absence of a separate cord between the set and the 55-type control unit. If the control unit is hidden in a wiring closet, the mounting cord leads are used, because the assumption is that the 25-pair cable is threaded through walls and ceilings, back to the equipment. If the control unit is stuck under the victim's desk, then a separate 10-conductor cord could be used to provide the leads.

If common bell cut-off was specified, the Y/Sl leads could be re-routed in the closet through the K1 relay contacts in the 55-type control unit, or they could be fed through extra conductors in the 10-conductor cord at the desk location.

I often ran a 25-pair and an extra 4-pair in places in offices that seemed likely to need a few more pairs, especially if the cables were being run in conduits. The amphenol hung out of the wall plate, and the 4-pair was left coiled inside the wall, where it could be terminated later on a 44A block or whatever piece of equipment for which it was required.

This turned out to be a good idea in offices where the system was migrated to a ComKey 416 system, which required that the CO T&R feeds be fed to the primary stations on separate pairs. (i.e. not stealing the Violet leads)

The ground returns for the ringer and the buzzer could use the A1 ground, in a pinch, and that would also provide an extra pair. The unbalanced condition of using half-pairs for ringer and buzzer did not cause any appreciable cross-talk on relatively short runs (under 100 feet) from the set to the closet, where the unbalance was corrected to a balanced pair via the cross-connection field.

What are ground returns? Do I want to know?

Ed,

I think they arrived today, but I wasn't home to collect, so the post office left me a notice of delivery. I'll go pick them up at the post office tomorrow.

The 564 came after the 565!? <scratching head>

Could someone give me a run down the role played by the "A" leads? If I understand correctly, they are the control pair for the line, but what exactly is being controlled? Lamp flashing? Sorry for the ignorance! HA!

A leads actually do several things: When just going off-hook, they close a relay causing the line's lamp to light. This is done by a ground being placed on the line's A lead.

If the line is in use and the ground is removed from the A lead, it causes another relay to operate placing a high-resistance short on the line to hold it and changes the lamp from steady to winking.

On an incoming call, when going off-hook, the A lead also stops the incoming ringing that is usually generated within the KSU unless bridged CO line ringing is being used.

Note that all relays mentioned are components of the line card itself. The KSU does not have any "intelligence" at all. The only electronics to speak of are within the power supply.

The interrupter is also a part of the KSU which is a motorized contact switcher providing flashing lamp, winking lamp (hold) and interrupted ringing. The motor in the interrupter is under control of any line card in the system that seeks these services.

Jeff: "Ground return" simply means the wire that completes a circuit from a device that had a "hot" lead activating it. For instance, the 10 volt AC lamp supply goes to the lamp, through the lamp, and back to system ground. That's the ground return for that lamp.

Cat6: The 564 predated the 565 by several years.

The "A" lead is one of three leads that are switched when a line key is depressed. (We say "key" rather than "button" because historically, people operated keys, going back into the days of telegraphy. Buttons are those little things that are on a TT dial or hold your shirt together. That's why these things are called "key" systems.)

The line key makes three leads: the Tip, the Ring, and the "A" lead. You know what the T & R do, and the third contact on the line key operates the A lead, which takes A1 ground (present in the tel set on the O/W lead, via the break contact on the HOLD key,) and sends the ground via the switch-hook and the A lead to the line circuit relay associated with that line. This relay can be part of a hard-wired group of relays (as in 1A1 systems) or on a 400-series printed circuit line card (in 1A2 systems.) The line relay operated sends lamp battery to the lamp lead of the line on all sets, and prepares the HOLD circuit. When the sub hangs up, the A lead opens, and the relay falls, releasing the line lamps. If the sub presses the HOLD key, the A ground is released just before the T&R are released, due to the mechanics of the HOLD key/line key linkage, and the line circuit starts the interrupter, switches the lamp lead from steady supply to wink supply, and the line lamp indicates a HELD line by the winking lamp. (120 ipm). On an incoming call, when the sub presses the line key and goes off-hook, the A lead serves as a supervisory lead, tripping the ring, changing the lamp supply from flashing (60 ipm) to steady.

Got it now?

Thank you Ed and Arthur for that I will have to slowly read through both posts several times to get a firmer grasp, but my understanding of the concept is losing some viscosity

Ed,

I knew the KTU is the "brains" behind the operation so to speak

Cat 6 -

Originally the KSU was an empty box that held a slew of relays that were field installed and hand wired together by the Installer. Later iterations offered prewired relay packages (grouped by line). Still later, the relays were miniaturized and put on circuit boards. That's what you're going to see. All current KSUs have their origins with this equipment. It was the gold standard for Telephones for a generation (or three - depending how you count).

Sam

SilverSam,

From what I gather, the KSU doesn't sound all that different from a PBX, except that the PBX will contain all printed circuit boards instead of KTU cards. So the PBX is kind of the digital offspring of the KSU.

A bit simplistic, but not too far off the mark. That's a good way to make a comparison. The carcass itself doesn't do much but to provide slots and power to the cards. It is the cards and their connections that make things happen.

Cat 6 -

A KSU is a Key Service Unit. It services Key (multi button) Telephones, which usually pick up all, or many of the same telephone lines. There is no switching capability within a KSU.

A PBX is a switchboard (Private Branch eXchange). The original PBXs were cord (plug) boards where the switching was done by the operator. Later machines were PABXs (Private AUTOMATIC Branch eXchange) where the switching was automatic. Early models were mechanical, later they were electronic, recently they became digital.

In short a KSU allows many phones to access the same line or lines and share them. A PBX will bring both outside lines (trunks) and telephone extensions (sets) in and allow the connection between the two via a switching matrix.

I don't think I explained this terribly well. If I didn't, please advise me and I'll try to do better tomorrow, when I'm not so tired.

Sam

Sam, on point. Ed, egg-zac-lly.


Sam, if you did it any better you should be named Professor Sam.

Maybe we should promote him to GoldenSam.

That was a great explanation SS. Thanks! I know all about switches. In the world of networking we deal with them all the time.

Cat 6 -

You're welcome.

I teach a class on switching for the IBEW. It's a 3 part class - Voice, Data & VOIP.

Voice starts with mechanical switches (Stepper & Crossbar), goes to electronic and then to digital.

Data starts with Hubs and then goes to Bridges, Switches & Routers.

VOIP shows the convergence.

Sam

So she's up and running! I love the clicking sound coming from the KSU when a call is coming in! Plus the lamp flashing on the KSU is also a hoot!

Two problems though. I have a lot of noise on line 2, and line 2 does not ring when called, although lamp does wink.

I'll post pics once it's nice and pretty and all.

I'll try twisting the pairs more thoroughly. Maybe it'll get rid of some of the noise on line 2.

Yes, help indeed!

For someone who just found out what tip and ring meant less then a month ago, I think I'm doing pretty good. I think there's noise on line 2 because the connectors are not punched down particularily well. (I don't have a punch tool).

Of course I may be talking complete nonsense, but if I knew everything already I wouldn't be here.

Quick question:

Thanks to Ed's expertise, I managed to get ringing on line 2. Problem was I had not connected a jumper between CA1 and CA2 (I only have two lines, so I don't need more).

But there was another jumper running between one of the B1's and R1's that I removed, and things aren't going well since I removed that one.

Could someone tell me where I would have to apply that jumper, since I can't remember from where I removed it? (Alzheimers at 35, not good)

Many thanks.

Not true. I know everything already, and I'm here.

Strap the CA ("Common Audible") terminals for as many lines as you want to ring at the same phone(s).

Wohoo! There be life in them old wires!!!

Thanks to Ed's unquestionable expertise, my KSU 551 is now fully operational. Somehow I had managed to blow the 10VAC fuse. Luckily there was a spare next to it. I also placed a jumper between CA1 and CA2, and I get two sweet rings.

All's good. Lamps flashing, bells ringing. I'm so happy I could cry! I really thought I had killed the unit by removing the jumper between MB and LB.

Arthur, obviously modesty is one of your virtues.

"Motor Battery" and "Lamp Battery" if memory serves me correctly....

I'm not too forgetful....as justbill says "I can hide my own Easter Eggs".......

Yes, motor battery and lamp battery as Ed told me. I can't quite figure out how a battery comes into the equation, since the unit is plugged into a 120 source, but I'll take it one step at a time

Battery is just terminology that the Bell System used to refer to voltages being provided by power supplies. Maybe this dates back to the days when power for the phone network really was provided by batteries. Who knows?

Our resident vintage Western Electric guru (Arthur P. Bloom) might chime in with a real answer to your question.

I'd be happy to know half of what he forgot.

Battery in reference to dc voltage v AC voltage,and yes I have even worked on manual I/C with the big "Blue Bell" 1.5 batteries hanging on the wall in a canvas bag ( Bell system Logo on it no less)