Jim Redelfs wrote:
In article ,
The Daring Dufas wrote:

Party lines use different ringer frequencies for each customer.

I respectfully disagree.

Two-party service (2FR) signals the "ring party" by delivering ringing
current on the ring side of the pair that passes through a
specially-wired telephone to ground. The "tip party" is signaled by
ringing on the other conductor through a specially-wired set to ground.

4, 6 and 8-party service also uses the above technique on a single pair
but uses distinctive ringing patterns assigned to each party. Example:
Two, short rings.

On an eight-party line, only FOUR parties hear ringing.

OBTrivia: Multi-party service was originally required due to inadequate
infrastructure (not enough pairs). The customers were "bridged" in the
field.

As enough pairs became available, many subscribers re-graded to private
service (1FR, 1FB, etc). Those that kept their two-party service were
bridged in the Central Office. This allowed for easier trouble shooting.

As party line subscribers died off, moved or re-graded to 1FR, their
former partymates enjoyed virtually private service at the lower,
two-party rate.

About once a year, the business office would call these "bridged alone"
subscribers and offer them a private line using Measured Rate service
that was about the same price. About half of these folks would
re-grade. Those that didn't were in for a surprise:

The Central Office Technician would then connect each remaining, bridged
alone subscriber with a new partymate. Most of those would then
promptly call to change to private service.

New technology, I'm 45 years behind on that one. I haven't
seen a party line in that long but it was the different
frequency response ringer type, all the ringers would tap
whenever anyone on the party line was called with only the
called party getting a full ring. It was in a rural area
and hunters were always putting buckshot through those nice
lead cased overhead lines. "Maw, the phones out uhgin."
"Dang that Earl, he don't never know what he's a shootn at."

TDD