History--Bell 761 PBX for motels

[HAncock4]

Recently, we discussed some PBX features offered by the Bell
System. In the 1950s, the Bell System developed a variety of
new dial PBXs with features to meet more sophisticated
communications demands from customers.

One new system was the 761 PBX, which was intended to be a
low-cost system designed for the needs of motels. I don't
know how popular it was; to me it appeared that many smaller
motels and hotels used conventional manual switchboards
(the 608 was very popular, though older places could use
a 551 or 555.) The larger/fancier hotels had dial systems.

The 761 did require that every room have a four-button keyset,
and that the hotel guest select one of the buttons prior to
making a call (see below), depending on the type of call to
be made. I wonder if that led to some confusion on the part
of guests.

The following is extracted from both the Bell Labs History
1925-1975 and the Bell Laboratories Record of July-August 1964:

During the latter 1950s the United States "took to the
road" in ever-increasing numbers, and the hotel/motel
business expanded enormously. Conventional PBX systems,
used in considerable numbers for guest communications in
hotels and motels, were usually tailored to the type and
size of the hostelry. Among the new features introduced
was one that permitted reaching frequently called numbers
(such as the registration desk, valet, room service, etc.)
by dialing only a single digit. Also introduced in 1958
was a "message-waiting" feature, which is probably
familiar to most travelers as the lamp on the telephone
set, which flashes if there is a message at the desk. The
essence of both of these features was extreme simplicity
at low cost, an objective met by innovative circuitry.

Enormous expansion has taken place in the motel industry
in the last few years and all signs indicate that this
growth will continue to accelerate with the recent
introduction of prefabricated units. One of the many
objectives of the Bell System is to keep pace with such
growth by providing adequate communications facilities
designed to met the particular needs of this type of
customer. For example, the recent introduction of Guest
Dial service for larger hotels and motels has received
enthusiastic acceptance and more and more of these larger
establishments are converting to this new service.

Guest Dial service permits a guest to dial his own local
calls and to place calls directly to a long distance
operator. For charging purposes, the local calls are
automatically scored on an individual- per-room register
located near the hotel desk. Long distance time and
charges are reported by the toll operator to the hotel
attendant at the conclusion of each call. This new service
also includes a Message Waiting feature to advise the
occupant of a room that a call was received for him during
his absence and that the caller had left a message with
the hotel attendant.

Later, in 1962, a special PBX designated 761A was
developed to provide telephone service integrated
with new features, at a cost that would permit economically
attractive rates to the small motels that predominated at
the time. The control position contained message-waiting
keys, and message registers to tally local calls.

The 761A PBX is a small self-contained crossbar system in
which all internal and outgoing calls are originated
merely by pushing a button. It features message registers
for the lines and trunks, Message Waiting, Direct Station
Selection, and Remote Answering when the "desk" is
unattended. It is available in 20-, 30-, and 40-line
equipment sizes.

Switching equipment for this new PBX consists primarily of
wire spring relays and crossbar switches. The basic
cabinet is arranged for 20 station lines and growth in
groups of 10 lines is provided by plug-in units to
increase the station capacity to 40 lines. The local
central office trunks and trunks to the long distance or
toll operator may be provided in any combination of from
one to eight plug-in units. From one to three
intercommunicating trunks may be provided as required for
room-to-room communication. Two "hold" circuits are
provided to permit the attendant to handle several calls
simultaneously.

Switching is accomplished by the operation of the crossbar
switches under the control of a common group of circuits
and by the line and trunk circuits.

In this new system, each room is provided with a
conventional four-button key telephone set which has an
exclusion key. Three of the buttons are arranged for
nonlocking operation and one is blocked inoperative. Calls
are originated at room telephones by lifting the handset
and momentarily depressing a nonlocking button
corresponding to the type of call being made. For
instance, to make a central office call within the local
calling area, the momentary operation of the LOCAL button
will automatically connect the caller to central office
dial tone after which he may dial the desired number.
Calls also can be made to the hotel or motel desk or to a
toll operator by depressing the DESK or LONG DISTANCE
keys, respectively. On these calls, the caller will hear
an interrupted ringing tone during the ringing period.
Local and long distance calls are made solely by the guest
without any assistance from the desk attendant.

The console operates in the usual cordless fashion.
The clerk may reset any room local message register at
any time. The clerk also a key for each room to light
the Message Waiting lamp.

A new feature known as "Remote Answer" has been included
in this new PBX. This feature permits the attendant to
answer any incoming calls from any room telephone when the
desk console is unattended. A dial completion feature is
provided whereby the attendant can extend a remotely
answered call to any other room telephone by flashing
the switchhook and dialing the desired room.

A group of trunks is provided for completing long distance
calls. These trunks are wired directly to the [Bell] toll
operator positions and are arranged to return an audible
ringing tone to the caller when they are selected from
either a station or from the console. They also are
arranged to allow the toll operator to re-ring the PBX
attendant immediately after the call has been completed
to pass the time and charge information and the
caller's identity to the motel attendant.

* * * * *

Perhaps some readers here will share their motel/hotel old PBX
experiences. Also of interest would be a description of modern
PBX's and the new features they provide for motel/hotel service.

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