Re: Bell 607 Dial PBX Cord Switchboard

TELECOM Digest Editor noted in response to snipped-for-privacy@bbs.cpcn.com:

[TELECOM Digest Editor's Note: The 607 came out in 1950, and that was > what we had at University of Chicago (actually a 26-position, broken > in two groups of 12 positions and one group of 2-positions) when I > worked there in 1958-62.

This must have been a very interesting installation. I wish I could've seen it.

I presume this was run in a no-nonsense strict manner like Bell exchanges. Most PBXs of any reasonable size strictly required the attendants* to be "Bell trained", that is, have previously worked for Bell as an operator. It wasn't just knowing how to work the keys and cords, but also the discipline of handling a high volume of call traffic without getting confused. Telephone operators were taught to "overlap", that is, pull up the cord in advance ready for the next call while you were serving the current one and to use both hands independently. It was one thing to properly know how to work the keys, but quite another to do so in high traffic. Pretty amazing to watch.

*Bell called its own people "telephone operators" but called people at PBXs "attendants" to differentiate. The general public called them operators. At PBXs "trunks" were lines from the PBX to the central office while "stations" were lines to extensions. The use of the word "line" was somewhat discouraged as it was vague. In practice terms were mixed.

I'd also love to know what Bell charged to rent the switchboard, dial exchange behind it, trunks, extensions, and other parts. I think back then everything was a la carte without combo packages. The tie-plugs you mention were extra. (Did you mean tie-jacks?)

The Eng & Sci history says such big boards were custom designed and built since there were few customers for such large equipment. Most PBXs were pretty small and mass produced. I wonder how many 24 position PBXs were in the Chicago area, probably not very many.

('test for busy' meant touch the tip of your cord to the sleeve of > the plug on the board; if you heard a 'crackle' sound of static in > your ear the line was free and you could use it; if you did _not_ > hear the 'static noise' it meant [and your report to the caller was] > 'line is busy')

I once read how they designed the circuit to do a busy test, it was kind of tricky. I don't think the callers heard the click the attendant heard since it was on the sleeve, not tip or ring. Circuit design did lots of things with the sleeve part of the connection; in central offices sleeve tests were used for early billing and ANI. Small non-dial switchboards of course didn't need a busy test nor did it work on them. All dial boards had to have them as to multiple manual boards.

Certain jack strips had in-use lights so a busy test wasn't necessary, I guess they didn't want to take any chances. This included trunks and some tie lines. On some boards there was a separate row of lights, on others a light glowed behind the designation strip.

The extensions could all dial each other of course

Many dial PBX networks had all sorts of dialing procedures between sister organizations. Many PBXs had both 3 and 4 digit extension numbers, for example. Some tie-ins required a prefix code first. A department store with branches could have a number of tie line codes between stores and to the main store.

And yes, it was otherwise a 607 board in terms > of automatic ringing/flashing-back/ etc.

That must have been a big help to productivity and good service. In the hospital I was at, the operators weren't too good at checking supervisory signals. Outside calls got a single ring and that was it; they were busy taking more incoming calls. They were poor on responding to flashes for a transfer or assistance request.

Operators served as gatekeepers, outsiders weren't allowed to call certain extensions, such as patient rooms late at night. All toll calls had to be dialed by the operator with a toll ticket and time & charges obtained. Bell would call back with T&C which would be placed on the toll ticket for internal or patient billing. Calls to incoming patients were made collect (ie to tell them to come to the hospital); I thought that was tacky. Again, I believe in those days (1971) every call was charged at retail, not bulk discounts.

Indeed, I think the hospital was a bit frugal and should've perhaps had another operator at peak times. They also had many key systems that didn't have any lights to save a few bucks. The two page operators handled a lot of traffic and that was the toughest job since it included keeping track of doctors' coming and going. (The operator sat with a clipboard scrunched in her lap, quickly squibbling in/out.) They did take the page operators off the switchboard and give them Call Directors and a desk and a "meet-me" page plus beepers which helped somewhat. IIRC, 1 (dial 1) was the staff page (interns, residents, nurse supervisors) and 8 was the doctor page (all other doctors).

I really wish I had taken some high quality photos of that board before it was moved out, but by the time I got a camera a lot of time had passed by and no one knew me; would've been awkward just walking in off the street.

All the student dormitories, faculty housing and the > 'International House' (sort of a 'YMCA-like' place on campus) all had > their own switchboards as well, all of which had extensions from our > main board _plus_ their own 'outside' 7-digit numbers to use as their > incoming/outgoing lines.

This was a very common arrangement in many organizations. At our hospital the x-ray dept had its own PBX and outside number (a modern Call Director style console).

As you described routing outside calls for a sister unit , some organizations wouldn't do that to not tie up tie lines; they would tell callers the outside number and make them dial. At the hospital, if someone was calling long distance or put up a fuss, they would pass the call through reluctantly. On tie-lines to a rehab facility, they had to do some sort of flip -- dialing the extension with the front cord, then quickly putting in the back cord in a separate jack (the tie lines had two rows of jacks.) Somehow I don't think their little flip was a Bell approved practice.

I think about 1963-64 Illinois Bell decided the entire mess should be > done over;

Was it really a "mess"? Or was it just labor intensive handling the high volume of calls? Were hospital and college personnel satisfied with service or were their complaints of dropped calls, long answers, trouble getting through, etc? Were there enough trunks and dial equipment to serve everyone when needed at peak times?

At my hospital during peak times an outside caller might have to wait a minute before being answered. (Although unlike today the operator was ready when she did answer and ringing didn't stop until then; today they answer but put you on hold forever). Patients had trouble getting an outside line or attendant; not enough trunks for them.

they got University of Chicago to split the cost with them > fifty/fifty to install centrex;

I thought Bell rented everything. For a new Centrex, I thought Bell would charge rent and use that to amortize the cost of the system. For Centrex, there was the issue of putting the gear at the customer's location (which meant using up floor space) or at the CO. Presumably there'd be an "installation charge" and a steep one given all the lines involved, but still nowhere near the full cost of the new system.

For the organization like that, there'd be a tremendous saving in labor costs since so many of the callers could dial directly in without the PBX attendant. The phone book, letterheads, invoices, and literature would all list direct dial numbers.

I wonder what the rent difference was for Centrex vs traditional system.

My hospital clearly needed Centrex but apparently the serving CO had panel or 1XBar and couldn't support it. It would take some time before they got ESS (1980s?) and went Centrex. Because of expanding programs, I think they came close to running out of physical space for extensions on the face of the board. Again, I wish I could've visited and taken lots of pictures.

As an aside, the designation strips were printed with the names of whatever dept it was. Later on changes were made by Wite-Out and handwritten notations, new strips were handwritten.

Somehow the dial system could decode allowable exchanges and reject distant ones. People were allowed to dial out to the city and adjacent suburbs only, any other 7 digit call that generated a message unit charge was not allowed and no 1+ calls were allowed. How an SxS dial system manged to do that table lookup (and who maintained the table as new suburban and city changes came on line) is beyond me. Maybe the trunks were restricted at the CO by special arrangement.

In the city, when dialing a suburban location that kicked in message units, one would hear a series of various pitch clicks building the connection, similar to the clicks on a long distance call so obviously the CO gear knew one from the other. (For message rate or "limited" customers, a call used 1 unit but calls were untimed). For surburban calls, they were timed and the overtime units varied by distance. The system is still used today for metro area calls.

[TELECOM Digest Editor's Note: The 607 came out in 1950, and that was > what we had at University of Chicago (actually a 26-position, broken > in two groups of 12 positions and one group of 2-positions)

I realized that your 26 position switchboard probably would cost more to build today than a entire modern full featured dial system for the

5,000 extension organization. It's ironic how technology changes the cost of things.

In other words, in the old days, until probably around 1975, a manual cord switchboard was cheaper to build than the equivalent dial system to replace it. After 1975, electronics made dial equipment cheaper. The huge drop in the cost of electronics and concurrent growth in power (look at the cost of logic and memory chips in 1975 vs today) enabled automatic systems to be everywhere

Manual cord switchboards contained a lot of hardware that would be expensive to make and assemble today. Every station line required at least one relay, every cord circuit a few relays, and trunk circuits several relays. Keys, cords, plugs, and jacks had to be well constructed of heavy duty materials to withstand heavy use and wear. The keyshelf and jack strips were a forest of minute complex wiring. An equivalent modern PBX is stamped out from a few chips in mass production.

Operator's consoles are stamped out in mass production and instead of hard wired signals with very specific meanings, LCD and LEDs controlled by chips provide the info. No mass of wiring.

As mentioned, I do feel some level of service quality has been lost by today's PBX attendants. They were not trained in the same service oriented manner as in the past and we all suffer as a result when we call organizations.

I forgot to mention in my earlier post that the Bell System provided a lot of freebies along with the switchboard; I doubt any of which is available today. They would train new operators or offer refresher courses. (I was so trained by a Bell person). They would monitor service and offer recommendations. They supplied the furniture.

[TELECOM Digest Editor's Note: University of Chicago and Illinois Bell/Ameritech always had a very close relationship. I do not know how much the board itself cost in monthly rent, but I do know that at least in the 1950-70's era, University of Chicago was the second _largest_ customer of Illinois Bell; their monthly 'phone bill' was about a million dollars per month; the 'phone bill' each month was delivered by United Parcel Service in a huge carton box, consisting of eight hundred to a thousand small pages. There was only one person at Illinois Bell who was authorized to make any adjustments on the account or for that matter even discuss it; University of Chicago was her sole account, she spent six or eight hours daily working on it. When there was any need of repair service, for example on the board itself, a repair person was there in usually 30 minutes.

I recall a _very hot_ Sunday afternoon when I reported for work on the afternoon shift (3 to 11 PM) with a giant-size paper cup of Coca-Cola. I came sashaying in a wee-bit late (like two or three minutes after 3 PM), sat my cola down, relieved the one operator on duty (despite the fact that we had 26 positions, on summer weekends or overnight when traffic was very slow there would only be one or two of us there; we used headsets with _very_ long cords and plugged in at the spot where most calls came through, then when a 'night bell' rang with a call elsewhere in the room we just unplugged, walked over there, plugged in and took the call, etc) ... anyway, I had just sat down and despite knowing full well the rule and the reasoning behind it -NEVER EVER SET A DRINK ON OR AROUND THE SWITCHBOARD- I took a sip from my cola, sat it back down and got busy with something else. I accidentally moved my arm in that direction, and the big, 24 ounce paper-cup of cola all spilled down inside the switchboard keys. Ooops! Board lit up like a Christmas Tree, night buzzer went off, and it was _very messy_.

I had the presence of mind to immediatly remove myself to a few positions away where I dialed out to 611 and told the repair clerk that a cup of 'Coke' had just been spilled in the board. The man who answered my call asked if I had any electric heater/blower around there and to set it up near the board so things would start drying out and 'I will have someone over there in 15-20 minutes'. Sure enough about fifteen minutes later a man got off the elevator, came over and looked at it, without saying a word, gave me a dirty look, and sat down there with his tools, unlocked the cabinet, got inside it with a little 'pick-like' thing and started scraping around and drying it out.

I sat at my new position very quietly, very humbly, not peeping a single word; nor did he speak at all. He sat there about 30-45 minutes picking away at all the tiny wires inside, occasionally muttering to himself. He finished his work, put the top back down, locked it in place, then took a rag and wiped around the metal keys a little bit. Finally he was finished, put his tools back in his holster and turned to leave, but he paused, looked at me and said, "You know, if I mentioned this to Mrs. Parsons (our chief operator) you would get fired -- be out on your ass! -- as soon as she heard about it." I knew that would be the case, and thanked him for keeping his mouth shut about it, which he said he would do (although the ten dollar bill I had in my pocket also probably induced him since it was a hot Sunday evening at that point and he had no doubt given up some of his day coming there to work on it. Mrs. Parsons never heard about it I guess, at least I never did hear about it. The next day was a day off for me but when I came in Tuesday one of the operators told me "something is wrong on that position; the 'action' is not quite right; a lot of crosstalk, etc, I think Parsons is going to make Bell come out and fix it or replace it." Oh ... is something not right over there, I asked innocently. PAT]

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