TELECOM Digest OnLine - Sorted: Re: City Party Line Service

Re: City Party Line Service
Thu, 17 Aug 2006 21:01:58 EDT

In a message dated 17 Aug 2006 10:58:36 -0700,

> When party lines are discussed, people usually talk about coded
> ringing and that everyone's phone rang with all calls.

> However, in city service this did not occur.

> The panel dial switching system, developed in 1922, included
> provisions for two and four party line service, which were common in
> those days. Each party had their own listed phone number and could be
> anything, not necessarily consecutive. There was no need for party
> letters. When calling a party line, the switchgear deteced the type
> of selective ringing and (bias and ground combinations) and sent out
> the appropriate ringing current. Only the desired telephone rang.
> This helped privacy since other parties wouldn't know the phone was in
> use.

I'm not sure what the invention of the Panel Type office has to do
with coded ringing on party lines. There were millions of SxS
connectors that were wired for terminal-per-station ringing, and
full-selective four-party ringing was the norm.

Two-party lines were almost universally full selective, using tip or
ring to ground to cause the property party to ring.

Four-party full selective ringing could also be provided in terminal-
per-line SxS offices, but there were many drawbacks to terminal-per-
line operation.

Wes Leatherock

Post Followup Article Use your browser's quoting feature to quote article into reply
Go to Next message: Jim Haynes: "Re: Computer "Logic" in 1922 Panel Switching"
Go to Previous message: Sam Spade: "Re: Clueless Hollywood"
May be in reply to: "City Party Line Service"
Next in thread: "Re: City Party Line Service"
TELECOM Digest: Home Page