atcomsystems.ca/forum
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 smile

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.


welcome 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! smile 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! smile 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 smile

Arthur, unfortunately I don't think I'll be seeing to much 25-pair cabling in my future career frown 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! laugh
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? welcome
Keep your sense of humor and smile....hang on for the ride of your life laugh .
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 frown , 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.... laugh
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.... laugh

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! smile

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 smile

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 frown 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! laugh
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! laugh
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! smile 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! smile John C.
It's done already. Now I'm just waiting for my KSU, and I'm in business. smile
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.
Quote
... like making a ten button set work on a 25 pair cable (three pairs per line, eight lines plus hold and ICM = 10 buttons).
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? laugh
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 smile 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 smile

Ed,

I knew the KTU is the "brains" behind the operation so to speak smile
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! smile 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.
help
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.
Quote
but if I knew everything already I wouldn't be here.
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.
wink smile
"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"....... laugh
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 smile
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. laugh
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)
Before A.C. was invented, batteries ruled the world. Therefore, by tradition, any supply that is used is called battery except the ringing supply (nominally 90Vac @ 20 Hz), which is called generator. Before ringing machines (motor generators) were invented, the subscribers and operators turned a crank on a magneto (generator) to produce ringing current (A.C.)

COTM's (Crusty Old telephone Men) refer to the paths through any circuit as "battery & ground" when trouble shooting. "Battery & ground make the world go 'round" is our mantra.

You will notice that the interrupter is a clever little goober. It has an ST lead ("start") a steady ground connection, and a steady battery (10Vac) lead. Each 400-D card has an ST lead that, when grounded, starts the interrupter motor on a single revolution. If the ST lead is still grounded, the interrupter motor will continue to turn, being fed a ground via its own internal contact. When the ST lead is opened, the motor will continue to turn, via its "windshield wiper" circuit, until it lands on its home position. Then it stops.

You can force this to happen by taking a test lead from ground to the ST lead and touching it momentarily. The interrupter will start, travel around one rev, and then stop at home.

It needs to stop precisely at its home position so that the next time it's needed, its contact cams will start at precisely the right point. On an incoming call, it is necessary to get the ringing cycle started as soon as possible to avoid "glare". (More on glare later.) Another reason it needs to stop precisely is that all of its contacts, in the home position, are closed. The lamps contacts and ringing contacts always are energized right as it starts. In the event of a power failure in the 10 Vac supply to the interrupter, (like your blown fuse) or a motor failure, the lamps will light steadily, and the ringers will ring steadily. It is done this way so that incoming calls would not be missed.

You will note that CO (Central Office) ringing is sent at the cadence of 2 seconds on, 4 seconds off. That ratio was developed by the Bell Labs eggheads as being just urgent enough to get people off the couch to answer the phone, but not so annoying that they took down the Remington Model 31 and blew the damned phone off the table. This cadence creates 10 rings per minute.

In key systems and PBX's, (generally used in office environments) the ringing cadence is 1 second on, 3 seconds off, making the number of rings per unit time higher. This creates more of a sense of urgency, and Ma Bell, being no dumb broad, recognized that an answered phone call is a billable phone call.

In large key systems, where there are many interrupters on many KSU's, the cacophony of many different cadences, starting and stopping at random times, would be an untenable situation. Therefore, in a particular system, one main interrupter would drive slave relay units, (412A KTU's) so that all lamps and ringers would be synchronized.

Glare: During the incoming sequence of a typical phone call from the CO, you will agree that if the incoming call were to be initiated anytime during the 4-second silent period, there would exist a statistical probability that an unsuspecting person might pick up the phone during that period. In a residential situation, that would be a bit unsettling, but would cause no great harm. Person A was calling person B, and B picked up the phone before A heard a ring. No big deal.

However, in an office environment, not everybody who USES a phone is authorized or trained to ANSWER the phone. A mailroom clerk is allowed to call out, but he is not really prepared to answer and direct incoming calls as would a receptionist.

The event of colliding, unintentionally, with an incoming call is called "glare." On manual PBX's ("cord boards") glare was reduced by instructing operators to use the highest-numbered trunk jack (usually at the right side of the row of trunk jacks) for outgoing calls, working their way down toward the left end of the row, as the incoming calls would come in from the lowest numbered jack, (left end of the row) followed by each succeeding numbered jack towards the right side of the board. This policy also had the effect of making the mechanical wear & tear on jacks (made of brass) more even, so that jacks would not need to be replaced so quickly. This instruction was always given to key system users, too. One should always use the highest numbered key on a set to initiate outgoing calls.

On key sets, ABR (automatic button restoration) was invented to help avoid glare. It forced a situation wherein users would pick up the handset before selecting an outgoing line. This avoided the sequence of picking up a handset on a line with an already-pushed line key, causing either glare or an interruption of a call in progress.

On PBX's it can be almost 100% eliminated by the use of ground-start trunks, rather than loop-start ones. I'll let Sam explain GS trunks, as my typing finger is getting tired.
Wow...how do you remember all of this information? I have been reading this thread and continue to learn something every time I look at it.
Jeff it's what COTM did before Tv; learned the trade, which you are trying to do and getting a good background in telephony.
Jeff, a COCP (crusty old college professor) told me that in order to learn something thoroughly, teach it. I have been teaching telephony either officially at the phone company, or unofficially to folks like you who just want to know these things casually, for 30 years.

I can describe every blue-collar operation there is, because I have done those jobs. From power technician to switchman to splicer, to installer/repairman, with side trips into management, business office, and Safety & Security.

On an interview for another facet of my life, I was once asked "What do you know about how the phone company works" and I said, rather flippantly, "I know how they take electrons and make them into pennies."

When I immersed myself in telephony, it was still being provided by the Best Telephone Company In The World. You can see from even my short description of the lowly interrupter how the whole system was designed to cover any situation. It truly was One System. The company would strive to avoid any unanswered call, so that revenue would be maximized, but they also would strive to avoid any foul-up that would diminish their reputation. Collisions, glare, wrong numbers, and delays in completing or answering a call were all to be avoided.

Contrast this dogma with just one item of telephony that you are familiar with in today's telephone environment: Caller ID. It seems like a great innovation, but I'll wager that it causes more confusion, missed calls, misdirected calls, and general frustration than any other "improvement" that has been put out there.

I have a cell phone (yes, gasp, it's true) and when I call people I remind them that the best way to reach me is at my business number. In a small town like mine, we just go by the last 4 digits, as a quick way of announcing our numbers. (There's only one exchange, SHelterisland 9 -- 749 -- and we dial all seven digits) People ignore what I say, and because THEY are using a cell phone, they take the easy way out and just hit "redial" and try to reach me via MY cell number. This screws up my operation, because now I have no record at my office of call details, and many messages don't get through to me due to the Babel Tower of so many competing cell companies and general mismanagement of the cell industry.

So, an innovation has caused a dilution of the old Bell System quest for perfection.

Stick around, and if you really want to know how the whole Big Machine works, guys like Ed, Ken, Sam, myself and the others will explain it. (Still waiting for SilverSomeone to chime in on Ground Start Trunks...)

Just remember, if you learn about it, we expect you to go home and hook up a small 1A2 system, so that the tradition will continue. To paraphrase a famous saying, "Once you go 1A2, you never go back."
Alright Arthur, I confess, I've been a little lazy. Probably still groggy after all that turkey.

Ground Start Trunks:

Loop Start Lines (Standard Telephone Circuits) were/are fine for most purposes. But for critical business applications they fell a little short.

It used to be (I don't know if it still is, everywhere) that if you didn't hang up when you finished your call on a loop start circuit, you'd get dial tone back again. This is especially bad on pay phones, because it lets you make another call(s) for free. It's a problem on PBXs when you conference someone in to an existing call and the third party hangs up and now you're conferenced in with Dial Tone.

It's also a problem with Glare (collision between incoming and outgoing calls).

Instead of just going off hook and completing the loop to get Dial Tone, you (the PBX) have to apply a momentary ground to the Ring side of the line. The CO recognizes a request for DT and returns a ground on the Tip side of the line. The PBX recognizes the confirmation signal and connects a load to the circuit, completing the loop. When the distant end hangs up, the CO opens the Tip side of the line and the PBX recognizes the disconnect signal and hangs up the line.

This "handshaking" almost completely eliminates Glare, the problems with third-party conferencing and people cheating on pay phones.

If I wasn't clear enough, please let me know and I'll try to elaborate it more clearly.

Also, there were other signaling methods that the phone companies came up with - Wink-Start, E&M (2 & 4 wire), Delay Dial and others. All these were part of the tapestry of Telephony that made the American Telephone System the best in the world.

Sam
Sam, exactly the correct explanation. We just need to remind the readers that we are talking about two-way CO trunks.

The one thing that made GS trunks glare-proof was the fact that as soon as they were seized at the CO end (for an incoming call towards the PBX) the CO circuit sent a ground out on the (normally open) Tip side, as you said. This grounded tip remained until the call was over; then it opened again.

The trunk circuit in the PBX saw that ground, and immediately made the trunk busy to any outbound attempt (an extension user dialing "9" for instance) by the PBX. This occurred either during the ring period, or the silent period, so that the 4-second interval of silence was never an issue: The moment that the trunk was seized, it was busy, and therefore no glare.
Arthur, I have room on my wall for a shoebox KSU smile
I just sold a couple on E-U-Know-Where. If I have another, I'll email you.

I owe someone a dial card retainer kit for a 500 set. Was that you?
It was for a 302 set...let me know if you have one.
"Once you go 1A2, you never go back."

I think that I am arriving at the point where I can say that I whole heartidly concur.

Arthur, I am gobsmacked to say the least by your knowledge of the trade. You understand the system, which for the most part, does not exist anymore (the understanding of the system I mean).

Techinicians today, are for the most part, parts replacers. Nothing gets "fixed" anymore, just tossed and replaced. It's like in IT. You have someone come in with a problem, and the technician concludes it's the motherboard. Well, you know the motherboard is a big place. What is it exactly on the motherboard that is causing the problem? Today, only engineers can answer that question, maybe. So, the motherboard gets tossed with 98% functionality, and the customer pays 700$ for a job that could cost 5 bucks, minus the man hours.

One more question if I may, and please pardon my ignorance, what exactly is the role of the interruptor?
"Instead of just going off hook and completing the loop to get Dial Tone, you (the PBX) have to apply a momentary ground to the Ring side of the line. The CO recognizes a request for DT and returns a ground on the Tip side of the line. The PBX recognizes the confirmation signal and connects a load to the circuit, completing the loop. When the distant end hangs up, the CO opens the Tip side of the line and the PBX recognizes the disconnect signal and hangs up the line."

OK, another question (questions rather) if I may. What exactly do you mean by Central Office? Like the telco HQ?

Second, how can you "return grounds"!? I know that across the live tip (+) and ring (-) connectors you have a certain amount of negative voltage (-48?), which is made possible by "putting ground on the positive" (another concept I'm confused about). How can you put ground on the positive? Very confused!
The central office is a mechanical or electronic switching system that provides dial tone phone service to your particular geographic area. In most cases, it is housed in a nameless, faceless building. This building may house multiple switches, including ones that belong to other phone service providers.

With regard to your question about grounds: Each phone line is usually delivered to the premises over a perfectly-balanced twisted copper pair. Unlike electrical wiring, the only time that either of these wires is associated with a ground is through an intentional and temporary connection. In the previous descriptions, the CO switch and the customer's PBX "talk" to each other by "touching" one wire or the other to a true earth ground. A lot more communication than voice occurs over that copper wire pair, and it happens very quickly.

Telco power plants have the positive side of the output grounded. This confuses many people because they are so familiar with automobiles, which are predominately negative-ground.
Most vehicles, cars, trucks, farm tractors, were originally positive ground until the mid-50s. In other words, the frame was "hot", not grounded. That is why in rainy weather the battery on the car would go dead as the insulating tires would get wet and drain the battery. Positive ground.... :nono: eek
Thanks Ed and Ken. You're all a great help!
Quote
Most vehicles, cars, trucks, farm tractors, were originally positive ground until the mid-50s. In other words, the frame was "hot", not grounded. That is why in rainy weather the battery on the car would go dead as the insulating tires would get wet and drain the battery. Positive ground....
I sincerely hope that you wrote that with your tongue in your cheek. I have never heard anything quite as preposterous.

There is no "ground" in a car. There is + and there is -. They are floating, and they have no reference to the earth. If you need proof, take an ohmeter and go from either side of the car battery to the earth. Tell us what you measure.
I remember the positive ground (frame) on the early tractors especially. Wasn't an earth ground, but it was still called ground.
I'm with Bill and Ken on this one Arthur. It's not a true "ground" but it's what it was always called.

At least that's what we always called it in Brooklyn.

Sam
I've never heard it called anything but ground. Negative battery terminal to car frame.
The interrupter is a 10Vac motorized device that has cams and contacts that deliver interrupted electricity as the cams turn. Steady generator and steady lamp battery are connected to the sets of contacts respectively, and the output leads deliver interrupted generator (1 second on/3 seconds off) for common bells, and interrupted lamp battery as follows:

60 ipm / 50% break for lamp flash ("LF"). Used to indicate an incoming call.

120 ipm / 5% break for lamp wink ("LW"). Used to indicate call Hold.

"Flutter" is a lamp supply that has an extremely rapid interruption rate (I seem to recall that it is 5 interruptions per second) that is not provided mechanically by standard interrupters. It is provided by an electronic timing circuit, and is used to indicate a call that has been placed on "I Hold" (pronounced "eye hold" -- the "I" stands for the person who placed the call on Hold, like "me").

I-Hold is a feature that is used in a large office (today they are called call centers) where it is is imperative that the person answering the call be the only one who can place it on Hold and retrieve it from Hold. This is important for a business that wants to ensure that an agent is the only one to talk to a caller, so that the caller is not inconvenienced by having to start his story all over again when the first agent places him on hold and goes to get some information.

Generally, I-Hold could only be offered on Call Director type telephones, with replaceable 598-type key strips. The first key strip usually has a red Hold key, and 5 clear (uncolored) line keys. Each successive key strip has 6 uncolored line keys. An 18-key Call Director (630 series) has three key strips, of 6 keys each, and a 30-key Call Director (631 series) has 5 key strips.

For I-Hold, the first key strip is replaced in the field with a special key strip that has a red Hold key, followed by a green I-Hold key, followed by 4 line keys.

To place a call on "regular" hold, the user presses the red Hold key as usual, and anyone who has access to the Held line can go back into the connection.

To place a call on I-Hold, the user presses the green key, and the line being placed on Hold can only be accessed by that person. The line lamp flutters at the "I" person's phone, and stays steady (or winks, depending upon the type of service requested by the customer) at all other appearances of the line.

This feature can be provided these days through software on electronic key systems. I am only vaguely familiar with electronic key systems, predominately the Samsung ones. On a Samsung Prostar system, if the user presses the red Hold key once, he puts the call on Hold. If he presses the Hold key twice in succession, he puts the call on "I-Hold." (I think they call it "priority Hold" or something like that.)

If you would like to chat about the various 1A, 1A1, and 1A2 systems and their oddities, feel free to email me to set up a phone call. It's easier to ramble on and on about this stuff by voice, rather than by teletype, like this.
AWWWW-----the good old days....and if the battery was low/dead....grab the crank. The starter just spun the engine to get the magneto firing....same for the crank.
I didn't say that it is not CALLED "ground." I said that it has no earth reference, and therefore cannot "leak" to earth through wet tires. Go set a D cell on the wet sidewalk, with its positive button facing down, and no other connection to it. Tell me if it runs down.

The "ground" side (negative or positive) is called that as an easy way to differentiate it from "hot." It could just as easily be called "return."

(The British refer to it as "earth" but they call everything that is grounded "earth," so that's irrelevant.)
Sorry, again off topic....but.......
Gee....Arthur, can you still set the cam on a reperforator? Ribbon feed vs. tape feed? Ratchet pin vs. wire? Ever use an optical reader on that TTY? Use burst? We had TTY set up for high speed UHF radio signal at the MidWest Relay....real fun.

Yes, the good old days....aren't we glad they are gone? laugh
I am constantly scolding my teenagers for walking around like Zombies, "texting." I call it the "cellular telegraph" and they look at me like the Luddite that I am. I'm sorry, but the telephone is a perfectly adequate way of communicating, I tell them, and my salary from the telephone industry has provided you all the goods and services that you need or want. Why have you regressed to a technique from the 1860's? I ask. Sheesh.
:rofl: :scratch:
off topic, but on a Cisco router when you program the console connection, the command is
'line con vty', which stands for Virtual TeletYpe...
just some useless trivia!
Aah, texting...the way my generation communicates...my parents just don't understand laugh
What get's me about texting is when the participants are adjacent to each other! I suppose that way, no one can eavesdrop, and they can say things they don't want others to hear. If that's the reason, maybe they need to find something more productive to do? frown John C.
Cell phones (they are not telephones, they are radios), are hellspawn.

I refused for a very long time to use a cell. My last job forced one in my hand.

When I wasn't using a cell, one of my friend's from high school asked me how people would get in contact with me. I said: "They don't." HA!

Call me at home, if I'm not there, leave me a message and I'll get back to you. WHAT'S SO DIFFICULT ABOUT THAT!? IT WORKED FOR THE FIRST 25 YEARS OF MY LIFE!

Cell phones...the ultimate way your pr**k of a boss can keep you at work 24/7.
Guess I didn't pay much attention when I posted. These post are drifting all over the place. Let's get her back on topic. Thanks. topic
I love this thread...some of you guys are absolutely brilliant!

I'm starting to get a 1A2 craving, myself!
OK, back on topic:

I think I screwed up when I rewired the cord to my 564. If you recall, I rewired it as a 565, with an individual ground for each lamp. But there's a problem.

I get DT for line 1 and line 2 (only have two lines total), but when line 2 is recieving incoming call, the lamp lights up very dimly, in unison with the lamp for line 3.

The lamp works fine for line 1

I was wondering if it had anything to do with the way I wired the A and AI connectors.

Inside my 564, the AI terminals are in a row above the line terminals segment, with a letter code facing the rear end of the phone.

The letter markings for the AI terminals are as follows from left to right looking at them with the rear of the phone facing you:

B(or 1B, can't really make it out)
EB
EH
ET
ER
then two terminals marked as SG.

The corresponding A terminals are
1H
2H
3H
4H
5H

The way I wired them is as follows:

1H-white/orange
B(or 1B)-orange/white

2H-white/slate
ER-slate-white

3H-green/red
ET-red/green

4H-blue/black
EH-black/blue

5H-brown/black
EB-black/brown

I don't know if that's where the problem lies.
Woha! Look what I found!!! Coolness!

565 wiring diagram
That's the BSP for a 565. It is different from a 564. Want me to fax one over to you?

Look for the number of the actual key that is in the phone. Is it a 589H or a 636A?
That site has a lot of BSP's...good information.
Arthur,

I had to wire it as a 565, because amp connector on the cord I bought does not have jumpers soldered onto it, daisy-chaining the LG's.

In any event, I already rewired it according to the diagram, and everything seems to be working fine, however, it would be great if I could get the diagram for the 564 as well. Thanks for the offer!

I'll pm you my fax number.

Jeff,

You're welcome smile
"because amp connector on the cord I bought does not have jumpers soldered onto it, daisy-chaining the LG's."

In that case, would I be able to daisy chain the LG's on the 66 block? :idea:
BTW, does anyone have a MOH KTU? Are these programmable, or is one just stuck with whatever music the manufacturer stuck on it?
There are two basic types (at least)of MOH KTUs. There is the ITT 403 that is an isolator card. This lets you have MOH without getting crosstalk on the dialtone lines. Most 400 cards require a KTU of this type. Some don't (I don't remember off hand which ones don't, but they're rare.) Some systems (The WE Comkeys I believe) had this isolation built in, but I can't speak to it as I never really worked on them. The WE & ITT 400Es did need the 403.

The 403 would not plug in to a normal 18 pin slot. If you didn't have a panel with 20 pin slots (most didn't) you had to add a 359 (single) or 259 (double) 20 pin adapter panel (or similar).

Then you have the SanBar FM radio card, that was an FM tuner on a 400 type mounting. Plug it in and pick your favorite FM radio station.

Some of the early "fancy" Japanese 1A2 type systems had a built in MOH. The Tie 1030 (Grey Whale) had a thing that looked like it came out of your grandmother's music box. It played anything you wanted as long as it was "Annie Laurie".

Ask away. I'm amazed I can remember any of this stuff.

I'll ask the other Cranky Old Timers to double check me. Please. I think I remember this stuff and then I begin to doubt myself.


Sam
Does my KSU 551 have 18 pin slots? Could I use an ITT 403 on my KSU? And what kind of music does it play?

I would prefer really tacky elevator music.
How about this little guy:

451 KTU
I believe the 451 is the WE version of ITTs 403. Arthur is much more up to speed on WECO stuff, he'll hopefully chime in soon.

Your 551 has 18 pin slots. Again these units do not provide the music source, only the isolation. Any source, including a transistor radio will work. Clip the bud off a earphone jack and hook that up.

If you only provide music to line 1 you can skip the isolation card.

Sam
Sorry Sam, but I don't understand what you mean by "isolation".

Also, what do you mean by the "bud" of an earphone jack? The plug? And hook it up where?

Sorry for all the questions, but I'm really green in this area.
OK, I think by "bud" you mean the earpiece (sorry, I only speak Canadian laugh ) OK, no problem, but where do I connect the wires?
OK, ED answered my question in this thread:

MOH
Ed wrote:

"With the LC400E, only one line card in the system can have music on hold. If you connect the same music source to more than one card, callers will be able to talk to each other while on hold, something I am sure that you DON'T want. In order to isolate them, you'll need an ITT K403 MOH card in a separate mounting, which is all but impossible to locate anymore.

If you only need MOH on one card, you'll need to connect the music source to pins 3 and 18 of the card slot itself. This means that you'll need to unwrap the existing wires on the pins, then insulate and store them. Connect your music source to these same pins and you'll be all set. Be sure to keep the volume low at first because if it's set too high, you will blow out the input transformer on the LC400E card."

Will this work on a 400D card?
I don't think so. I don't think that a 400D had contacts on pins 3 & 18. If you need a 400 E (or similar) speak up. I'm sure someone can dig one up.

And I'm compelled to ask. What does your signature say? (Please don't say "It's all Greek to me")

Sam
Morning SS!

Surprisingly, I actually have a 400E card. Bought it on the bay of E. If I could get my hands on two more, that would be great!

My signature line says (it's in ancient Greek actually) "If you're not a philosopher, you're not a Greek" laugh
Well, the other two won't help you unless you get an isolation card.

Sam
I can provide ITT K400E line cards, as well as a K403 MOH card and also the seperate mounting enclosure. Let me know if you're interested. Here's some pics of the enclosure, I'm not sure if it's what Ed is referring to or not....
Pic 1
Pic 2
Pic 3

I can also provide a SAN/BAR MOH tuner card, or an external VALCOM FM tuner if you're interested.

If it all looks like what everyone thinks ya need, pls PM me for further info -

Thx
Matt
I know Sam, but since I already have two lines, and am considering a third, I think I might go for the isolation card.

Quick question(s):

Pins 3 and 18, is that numbered from top down or bottom up?

Does it make a difference which wire I attach to the pins? I mean like, left ear bud to 3, etc?
D'oh! They're numbered. :rolleyes:
Uh, there are more then 1 wire connected to pins 3 and 18. which ones do I disconnect? They are cross connected to the other slots.
Well, I know for sure I messed up, since all I get now on line 1 is noise. No DT.

The wires that were connected to the pins previously were connected via what looks like little springs that wrapped around the pins. I couldn't get fancy like that and just wrapped the earphone wires as best I could around the pins in question.

It wasn't easy, there's not much room to move back there. I also accidentally disconnected the jumper that was connecting one of the pins on slot 1 with the same pin on slot 2. Tried to do a shoddy jumper job to repair that, but I'm quite sure I messed up.
How does the enclosure connect to the KSU?
Jeff,

From what I understand, the back of the enclosure has 18 pins per slot. So I think you would just have to run jumpers from the pins on the enclosure, to the respective slot pins on the KSU.
Cat 6, spin-wrap the wiring on the back of the 359 and punch it on the KSU.

Spin wrap tool does just that...it allows you to make a concise wrap around the stud pin on the back of the adapter. If memory serves me correctly seven wraps with this tool equals a standard solder connection.
Ken,

What's the 359? The enclosure? Thanks for the input btw! smile
The 359 is an accessory 400-card TYPE panel with 2 slots. Note the TYPE, that means it will slot all sorts of 4XX cards, like the 401, 403, and a bunch of other special purpose cards. It's all in the wiring. Good luck finding one. frown By the way, what Ken calls a spin-wrap tool is also called a wire-wrap tool. Radio shack used to sell them, with their shift to mainly consumer type stock, they probably don't any more. Maybe Sandman has them in stock. Used to be a very common type of connection method. I saw the inside of a Cray computer once that was built in a circle. If you looked down inside from the top, it looked like an electrician's nightmare, because the wires were as short as possible. That meant zillions of wire wrap jumpers going ACROSS the 'tube', top to bottom. (Get it right the first time, because won't get a 2nd chance!) You need to practice a little before you do it for keeps. And stranded wire is a no-no. So solder or scotchlok some 24 gauge wire onto the stranded headset cord. And you may have to use smaller wire, depends on the tool you get. John C.
Thanks for that LH! I went and bought a 22-24AWG wire-wrap tool today. It was freaking expensive!!!

I think you do get a second chance, because the tool is also a wire-wrap removal tool as well, but I'll practice before I start for real. I remove dthe wire wrap on pins 3/18 yesterday using a pair of fine long-nosed pliers, so it's not that hard.

The cord coming off my headset are tip and ring configuration! Red/Green. From what I understand, tip comes from the "tip" of the plug, and ring from the...ring! hA!

Really flimsy wire though. Can't even call it a wire. Looks more like fabric, or thread. Don't know how I could attach that to anything, or anything to it.
Cat -

I think I read you also don't have a punch down tool. You are absolutely going to need one, not sure how you're getting reliable connections to your 66 block without one. When I started, I used a small flathead screwdriver to "push" the wire in, but the connection wasn't at all reliable and you're also left with excess lead hanging out.

Just my 2 cents, but I think connecting the enclosure is going to be enough of an adventure all on it's own... you for sure don't want to be wondering if your punchdowns are reliable or not.

Or maybe you already bought the tool and I didn't see it.

In which case you can ignore this post...

smile
"Really flimsy wire though. Can't even call it a wire. Looks more like fabric, or thread. Don't know how I could attach that to anything, or anything to it."

Solder a piece of regular wire on to it. Or use a solderless crimp conector.

Sam
Matt,

I have a punch tool. Thanks for the concern! I did the flat-head screwdriver thing at first as well. :rolleyes: It worked, but it wasn't exactly pretty.

SS,

I don't think they have crimp connectors that small. Is there a particular order that the earpiece cables connect to 3/18? Like left earpiece to 3 etc?
You are trying to use a stereo cable on a mono system! Use both leads from the right earpiece. And it sounds as if you have the good old fashioned 'tinsel cord' which is very fine (40 Gauge ?) copper wrapped around or braided with very fine cotton stranding. Almost impossible to make a connection to! Sooooo, take the plug/cord to your favorite hobby electronic store and get a replacement with REAL wire! Or, get just get a plug and solder some cross-connect to the lugs. Be sure to slip the shell on the wire first! smile John C.
What kind of end is on the plug? I have tons of 1/8 and RCA cables laying around so I can send you one if you need it!
Thanks for the offer Jeff, but it will cheaper for me to just go and buy one.

Can anyone tell me how to connect the wires to the plug? I've never even thought of doing this before.

From what I understand, there are three wires in all. One for each the left and right earpieces respectively, and a ground.

What goes where, what type of terminals are on the base of the plug etc.

Thanks.
It can't get cheaper than me just mailing one to you smile
Normally one wire is hot, one is cold, and one is ground. If you have a voltmeter, you can just check continuity. You want to check one wire to the tip, one wire to the ring, and one to the sleeve.
I drew you a diagram.
[Linked Image from i35.photobucket.com]
Once again, the phone system is mono, as in only 1 audio channel. You are apparently using a stereo source. Not a problem, try 'tip' and 'sleeve', I believe that will get you 1 channel of the stereo source. Don't even connect a wire to the 'ring' lug. And check with a buttset before you ever connect to the KSU. Test 1st and fix 1st. That way you will know that the source was good, before you hooked it to the KSU. Been there, didn't do that, wasted a lot of time. But only once! John C.
Thanks Jeff and LH. Will test 1st fix 2nd. I've learned this lesson long ago (not that I always abide by it smile )
Wire-wrapping is pretty niffty! Took me a while to get the hang of it, but I was reading that some people find it a superiour bond to soldering.
As I recall, the relays we used to pull out of the dumpster behind the CO were both wrapped _and_ soldered. Now There's a connection that ain't going anywhere.....
Matt, actually the 24 gauge and smaller wire was just wrapped. The larger wires, usually for power connections, were partially wrapped and soldered since the stiffness of these wires would often tend to twist/break the wire wrap pins.
Yeah, the larger wires on the back of my KSU are soldered on.
Cat -

One thing once you get it all going - everyone helped me do a similar thing with MOH (although in my case it was much easier due to the model of KSU I have), and I just wanted to share this with ya in case you think you did something wrong. The volume of the MOH is no where near what you hear in todays world. Ed, Sam, Arthur and Ken confirmed this for me; back in the day MOH wasn't there to entertain you, but just to let you know you were still connected to somebody. So.... don't expect the kind of ear canal shattering volume you hear in today's world. Also, while you're waiting for the shipment to arrive, you might start to give some though as to how you're going to mount the enclosure. I'm sure it mounted on some sort of rack back in the day, but you'll probably need to make some standoffs or something for it.

Once you go to all the trouble of wire wrapping 18 x 4 leads, you'll not want to risk one or more of leads breaking due to the enclosure just 'hanging' there. The pics I posted should give ya a starting point of what you're going to need to do.

Just a thought...

- Matt
Thanks for that Matt smile

I still don't know where to punch the leads (as KLD mentioned) coming from the enclosure. Punch them on the 66 block? As fas as I can tell, that's the only place you can punch anything on my KSU.

I'll wire-wrap the slot pins on the enclosure, but where they go from there, I don't know.

I was wondering Matt, do you still use your KSU? is that your home telephone system?

I have no practical purpose for doing this. I just find the technology very cool smile
Yep, I installed the full blown system, and outside of a payphone I have installed, trimlines in the bathrooms, and a standard rotary wall phone in the kitchen, everything else is 1A2, with intercom and MOH.

Wouldn't have been able to do any of it without this board. You're in good hands here.

I don't know where you're going to punch down to either.... I'm looking forward to this discussion/walk through.

One thing ya might do, I know that all slots share mostly common leads - in other words, on the back of my KSU, almost all the pins on each slot are wired in parallel. So while you're waiting, you could study your KSU to see what pins from what slots are common, and where they end up terminating on your 66 block. There's probably also a schematic for it that someone could point you to.

To cut down on the number of leads you're going to have to punch down, you could determine what pins will be common on the back of the enclosure, tie them together, and then in those cases you'll just have one lead to run back to the KSU. In other words, I don't see any reason why you'll have to run 72 (18 x 4) leads back to the KSU be punched down.
Yes, ofcourse, that would be a waste of wire. In any event, I'll only have the isolation card (for now) on the enclosure, so in essence, I'll only have to run one slot enclosure back to the KSU.

I want to set up a speaker system as well, since I use speakerphone regularily. Intercom as well.

Any idea where I can get a good deal on a rotary wall phone? Or a touch-tone version of the same phone?
EBay has all kinds of 'em. They come up all the time. A speakerphone is a completely different matter.

I can point you to a source for them, but you are looking at some fairly serious $$$..
I'll PM ya the source. Mine is a 4A, otherwise known as a "Charlies angels) speakerphone. Which, by the way, if the best speakerphone I've ever had.... one issue is it's half duplex, but there's circuitry in it that largely makes that problem moot. Keep in mind a 1A2 speaker phone comes (a least a 4A) comes in 3 parts - the speaker, an on/off switch (which also houses the mic) and a connecting block to hook them al together. Then there is a transfomer to power it.

When I was really into it, I'd search ebay every morning for "1A2". I haven't seen much lately, but another alternative is to search "Western Electric" and look through all the pages (50+). It will take ya about an hour, but a lot of people sell 1A2 keysets not knowing what they are, and so they don't even mention 1A2 in the ad.

Prices can range very broadly, depending on the rarity, date of manufacture, and condition of the keyset, as well as color. Sometimes you can come across an entire lot of them.

I have 3 TT 1A2 keysets I'd be willing to part with, green (avacodo), beige or white, all fully functional. I have other colors (red and black), but I'm not sure I want to give them up. Red 1A2's are pretty hard to come by, and I paid quite a lot for some of them.

I'll also point you to a site where you can get new or reconditioned 1A2 keysets, but again, pretty pricey.

Standard rotary (or TT) wall phones are a dime a dozen on ebay. Just search wall phone and you're off.

Also, one reason I paid a bit more is I insist on WE keysets. The ITT ones seem flimsy to me, although they function just as well. But you could kill an elephant with one of the old WE sets.... then make a call back home on it. The ITT ones... not so much.
Hey Matt, i'lll reply in earnest when I have more time, but it's the 4A speaker system I'm looking to setup. Talk soon.
Guys, it would be best to start up another thread. This one is 157 posts deep now and has covered a lot more topics than the original matter at hand. We need to keep threads clear and concise, not bouncing all over the place. Just start another thread about 4A speakerpones when you are ready. Thanks for your cooperation.
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