Getting a Dial Tone
Just 22 Steps
Just 22 Steps
Idle state- phone on hook
Idle state- phone on hook
48v is supplied to the subscribers phone via the LR relay coil and contacts K1 and K2 of the K (test?) relay
There is no current flowing though the LR relay coil
C1 is charged to 48v, because in the calling number generator has a 1k resistor connected to ground
Subscriber Loops line to operate LR relay in Subs line unit (SLU)
There is a pair of cables for each subscriber linking the SLU to the Calling Number Generator field (CNG)Â
