> I also lived in a dial exchange that had terminal-per-line step
> equipment. This meant there was one terminal for each line -- a party
> line had an additional digit. The number for my busines was 234.
> Individual (one-party) lines had three-digit numbers. Party lines had
> four digit numbers, such as 4551. The last digit (usually a 1 or a 2)
> told the connector which ringing current to apply.
On some SxS offices which a 4 digit number, the third digit would be
the party code. So I could be 5718 and my neighbor 5728, the 1 and 2
indicating the party code.
> This was long before DDD or the national numbering plan. Terminal-per-
> line had a number of drawbacks, such as the fact that if intercept
> service needed to be provided, both parties' numbers had to be
> intercepted and the caller asked which number they were called ... also
> regrouping party lines required changing one or both customers numbers.
This was one of the challenges they faced in implenting DDD.
Obviously some offices took longer than others to convert. Well into
the 1970s the telephone directories for small towns had complex
directions of dial codes depending on where you were and where you
were calling. Sometimes you had to wait for a second dial tone or
special tone. Adding tandem switching (switches that connect between
central office) was a challenge too.
> [TELECOM Digest Editor's Note: Am I correct in thinking that all
> party-line subscribers were geographically close to each other (such
> as a few doors away, or across the alley?) Were they nearly or always
> on the same cable out of the central office? Or were there party line
> subscribers across town from each other? PAT]
I would presume (and have heard) that party line users were located
close to each, since the whole idea was to share the same physical
line to the C.O. How it was handled in cities, where in the old days
many people had party service, I don't know.
Indeed, one of the postwar challenges of the Bell System was the
demand for private line service instead of party service as people got
more money and could afford it. Originally party service had a big
discount but as time went on it wasn't as significant. The paperwork
to track cabling and lines must have been enormous.
However, in some 1950s Bell System publications, they said one of the
limiting factors in giving more private lines (demand exceed supply)
was that central offices didn't have the capacity. Party service was
a way to keep down calling volume until they could expand. In many
cases that meant a new building which of course was expensive and time
consuming. (I know of city Bell Telephone buildings where it is
obviously some upper stories were added.)
I do wonder if any outside auditors checked to see if the Bell System
was indeed adding capacity as demand required in the 1950s. Could
Bell have bought gear from Automatic Electric? Hired more installers?
I will note that in the 1950s the military was expanding and Bell had
military contracts for both basic phone systems and advanced radar and
other systems. Other companies at the time did so as well, and this
was respected by the public. Companies in that era ran ads (similar
to that of WW II) "Defense needs come first -- please be patient". (It
wasn't until the later 1960s that some would question Bell System