ringing voltage is applied to the telephone set terminal
on the tip (1) and ring (2) terminals. It is then bridged
to terminals 3 and 4.
For two-party service, a third wire (common ring
return) is used and connected to terminal 4 of both
telephone sets. Ringing voltage is then applied to one
telephone set across tip terminal (1) and terminal 4 and
to the other telephone set across ring terminal (2) and
Restricted Telephone Set
The type G (R) restricted telephone set is used in
security areas where the chance of inductive coupling
of signals to the telephone set might compromise the
security established for that area. This telephone set is
equipped with a noise-cancelling transmitter, shielded
handset and deskset cords, and a push-to-talk (PTT)
switch. This set has a distinctive identification plate to
distinguish it from the nonrestricted set. The
identification plate has "Restricted" as the first line
and "(R)" after the type designation. The restricted
telephone set is also adaptable for high-noise areas
because of the PTT and noise-cancelling transmitter
Figure 6-6 illustrates a basic type G (R) telephone
set. This set will fit the same enclosures as the basic
Figure 6-6.--Basic type G (R) restricted telephone set.
type G nonrestricted set. Figure 6-7 illustrates a
handset and cord assembly for the type G (R) set.
Figure 6-7.--Handset and cord assembly of the type G (R) set.