> [TELECOM Digest Editor's Note:
> And _that_ is how City of Chicago came to have 312-744 for their
> phones (but now, in 2005 they have not only 744, but 745, and 747 as
> well.) PAT]
The City of Philadelphia had a Centrex for as long as I can remember,
MUnicipal 6-9700. During the bicennial they changed it to MU 6-1776.
IIRC they used the whole MU 6 block. Despite that, not all phones
were on Centrex and outsiders had to go through the City Hall operator
(a 24 position 608 switchboard split into two sides of 12 positions
each). The non-Centrex extensions had five digits and access codes
were required to reach between five and four digit extensions.
As to city offices in the field, such as libraries, local police
stations, playgrounds, etc., some had MU 6 numbers but some
had local neighborhood phone numbers. I could never figure
out a pattern.
In addition, the City had a full separate private PABX
(private dial exchange) that was old. It mostly served
police and fire stations and street call boxes, and hospital
emergency room desks, not so much city offices. Its phones
were immediately recognizable -- old AE sets with the nickel
ornamentation and a ratty brown fabric coiled cord. That
dated from when before radios and police and firemen used
street callboxes to call in. (Street callboxes were not
extended to newer postwar neighborhoods). I don't know when
that system was removed from service -- I've seen in use in
For street fire alarms, the city used call boxes. When the lever was
pulled, a clockwork would generate a coded signal denoting the
firebox. These were removed a few years ago. As kids, we were taught
to know where the nearest callbox was to our homes and to wait there
to direct the arriving firemen to the fire. They date from a time
people didn't have phones or speak English, and lasted a lot longer
than they needed to given universal telephone service.
The City was slow converting to Touch Tone. In the early 1990s city
telephone sets were still classic hardwired 500 sets with a nice
printed MUnicipal 6- number card. Finally they went to Touch Tone,
but plain 2500 sets. They added 685 as another Centrex to 686. The
phone directory lists a lot more prefixes to reach various city
offices today; I don't know how it is set up.
I've read City Hall (an ancient huge building) originally had DC power
and stayed with it until 1954, which was pretty late. In the early
days of electric utilities, some places put out DC instead of AC.
(There was a debate in the industry which was better and AC won out).
Old catalogs of the 1920s and 1930s list products in both AC and DC
[TELECOM Digest Editor's Note: City of Chicago used DC power (rather
than AC) -- at least in the downtown area -- until sometime around
1930. That's at least one reason why there were so many WUTCO clocks
everywhere, instead of 'regular' wall clocks. Clocks cannot run on
direct current; they require alternating current at 60 cycles.
The old city hall (Chicago) PBX on RANdolph 6-8000 had a _20_ position
switchboard, broken in two parts also -- 10 positions in a rank along
one wall, the other 10 positions along another wall. The only bigger
switchboard I ever saw was the one at University of Chicago when I was
working there, 1958-61 or so. It was 28 positions, but divided into
three ranks of 13-13-2, a rank against each wall and the smaller group
along a third wall. There were three groups of directory listed
numbers; main campus was MIDway-3-0800 (with 2xxxx, 3xxx, and 4xxx
extensions), hospitals were MUseum 4-6100 (5xxx, 6xxx) and the
Computation Center and Fermi Institute, NORmal-7-4700 (8xxx). From 6
AM to 1 AM next day, they usually had at least 20 operators on duty,
but in staggered shifts (a couple came in at 6 AM, a few more at 7 AM,
etc.) By 11 PM when I got there, two or three women were left. They
had all split by about 1 AM leaving me alone until when the day shift
started coming in a few hours later. Volume of traffic was such at
that time of night it did not warrant any more help. When something
'buzzed' (buzzers were turned off during the day, [just work from the
light blinking at you] but turned on overnight, sort of a loud sound)
I just walked over to the rank in question, plugged in my headset and
did business. Along the fourth wall were desks for the chief operator
and the clerk and the teletype machines and their clerk/caretaker.
The teletype machne hardwired direct to the 'Kenwood Bell'
central office (so named for the Bell central office at 61st Street
and Kenwood Avenue which served our lines) was used for time and
chargs coming in for long distance calls. The other one was hardwired
to Western Union for incoming messages. Another big board was the
one at Sears, Roebuck on State Street downtown (WABash-2-4600) which
was a five position board, serving the department store and the
credit offices upstairs. That one was busy also, it literally rocked
around the clock; our at UC at least slowed down considerably during
overnight hours. PAT]