History--Bell system PBX marketing literature [telecom]

In reference to the posting about a PBX needing a good home, here is some historical background material:

For younger readers, the 556 was a cord switchboard for moderately sized dial PBX's. The 556 was installed along with a dial switch; various types of dial switches could be used. Up to about 120 lines and 20 trunks could be handled by a single switchboard, two switchboards could be placed side by side to handle double that.

The 556 was similar to the popular 555, the 555 was a manual PBX. Both were released after WW II and featured improved circuits and easier maintenance. Because the 555 was manual (the attendant handled all calls), it was a stand-alone unit (see below).

In an installation with a 556, extension users could dial calls between extensions, and where authorized, dialed 9 to make an outside call. The PBX attendant answered incoming calls and routed them to the desired extension. The attendant also provided other assistance as needed, such as placing toll calls, keeping toll records, and screening calls.

In the 1960s, customers with modest dial PBX's began to replace their cord switchboards with new desktop consoles with more automated features. For instance, on a cord switchboard, the attendant had to take down the cord pair at the conclusion of a call; on a console, disconnection was automatic. On a console switchboard, an incoming call could "camp on" to a busy extension and be automatically connected as soon as the extension was free. The automation allowed the attendant to have other duties, and many doubled as the receptionist.

In the 1960s onward, key systems grew more sophisticated and replaced PBX's in small installations. Key systems didn't require a dedicated trained PBX attendant.

A Bell System marketing pamphet from 1962 says the following:

"The 556 switchboard gives your business all these advantages:

FAST, SEMI-AUTOMATIC OPERATION . Your telephone attendant completes calls quickly and easily with angle-mounted cords and keys. . Pushbuttons and positive visual control signals assure fast, accurate communications.

EXPANDABLE-VERSATILE . Expandable to match the capacity of your dial communication system. . Works with all kinds of trunks, tie lines and auxiliary PBX equipment.

MODERN-CONVENIENT . Attractive, low-silhouette design. . Can be custom finished to blend with your decor. . Can be readily installed as an integral part of your reception area. . Compact cord and key shelf add comfort and operating convenience.

MORE THAN PAYS ITS WAY . Your attendant handles more traffic in less time. . Simplified controls assure efficient call handling and better customer relations. . Prompt, reliable maintenance at no extra cost. . Readily expanded or altered without costly delays . No capital investment.

The 556 Switchboard...gives you faster communications for the efficient operation of all your business functions-- Administration, Purchasing, Production, Distribution.

Features: . conference calling . emergency service . night answering . tie-line service . connects to your paging system . expands with your needs"

  • * * A Bell System marketing brochure for the manual 555 from 1962 focused on cost control:

"PERSONALIZED HANDLING OF INCOMING CALLS . All incoming calls are screened by your attendant. . She completes calls quickly with simplified switchboard equipment. . Priority handling of special calls easily arranged. . After-hours calls can be routed to any "inside" telephone you select.

CONTROLLED OUTSIDE CALLING . All "outside" calls are made through your attendant. . Handles up to 13 outgoing calls at once. . After-hours "outside" calling is easy to arrange. . Permits accurate accounting of all calls. . control all calls. . maintain accurate accounting."

  • * *

The manual 555 obviously saved on the rental of dial switchgear, but this was offset by the expense of additional PBX operator time and the delay of an operator completing all calls. Since an operator was required anyway to handle incoming calls, the additional time to handle intercom and outgoing calls could be modest--it depended on the traffic of a particular installation. Sites with heavy intercom traffic would likely need a dial PBX, especially if that traffic continued after the switchboard was closed for the day. As mentioned, the 555 was a very popular switchboard, so plenty of sites were content to be all manual.

A single 555 could handle up to 120 extensions and 14 trunks. Two switchboards could be installed side-by-side to double that.

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HAncock4 wrote: :switchboards could be placed side by side to handle double that.

:The 556 was similar to the popular 555, the 555 was a manual PBX. :Both were released after WW II and featured improved circuits :and easier maintenance. Because the 555 was manual (the attendant :handled all calls), it was a stand-alone unit (see below).

I was at a resort in Wisconsin this summer that had a still installed (but disused) 555 at the front desk. The main building was built in the early 50s, so it's probably original. It had instructions taped to it, including some phone numbers (police, fire, hospital). The numbers had 920 area codes, which meant it was in use until the late 90s. That's a pretty good run for a manual switchboard.

the actual phones in use were Cicsco VoIP sets.

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David Scheidt

Until dial systems and computers became really cheap, the economics favored manual switchboards in modest sized motels and hotels:

1) The desk clerk handled the switchboard as an adjunct to his other duties. There wasn't much telephone traffic, so it wasn't a burden. Also, the desk clerk was the best person to answer general inquiries from rooms. 2) All outgoing calls from rooms were billed, so the desk clerk had to manually place them and record the charges. 3) A modest sized motel/hotel often didn't have many premium guest services, so there was little internal telephone traffic, such as requests for room service or a valet. 4) In the 1970s and even early 1980s, electronics were still expensive (consider what a high-end PC cost in 1983 in today's dollars.) So, a dial system would've been expensive as compared to a manual switchboard. By the late 1980s, the economics changed, and manual switchboards disappeared. 5) Even in larger hotels, sometimes manual telephone service was seen as a guest service; the operators were trained to answer common questions and assist guests. In a larger hotel, the telephone switchboard could be quite large with many operators serving the guests. 6) The hotel/motel market was significant for Bell, and Bell developed systems and features for them. Some larger hotels did get dial service. An instruction card would be fitted around the dial, and the guest could dial a single digit for room service, valet, and other services. There were registers to count local calls, and an arrangement with toll operators to return guest toll call time & charges back to the hotel.

P.S. While 555 was popular, another popular model was the No. 608 cord switchboard, which was a more modern version. This had a beige jackfield instead of a black, and an overall more modern appearance. Certain features (like ringing and flashing) were automated or simpler than older models. For instance, on an older switchboard, the attendant pressed a ringing key to ring an extension and the caller heard only silence. On the 608, ringing was automatic and the caller heard a ringing signal.

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