AT&T feature module 2 system manual Frequency Generator, See Figure

Frequency Generator

DESCRIPTION	If your basic carrier or expansion carrier has a 12-Basic Telephone (012)
	Module, you must connect a Frequency Generator to the Power Module,
	located in the first slot of each carrier containing basic telephone modules.
	See Figure 2-20.
	The frequency generator converts 117-volt, 60-Hz input power to 105-volt,
	30-Hz ringing voltage for basic telephones connected to the 12-Basic
	Telephone Module.
	FIGURE 2-20 A frequency generator.
			Frequency generator
		.	0

CONSIDERATIONS

HOW TO USE

You must remove each Power Module that has a 12-Basic Telephone (012) Module from its carrier before you insert the frequency generator. However, before inserting or removing the Power Module, be sure to turn off its power switch. If your system has an expansion unit, turn the power switch off on the basic unit’s Power Module first, then turn off the power switch on the expansion unit’s Power Module.

The frequency generator provides ringing power to the basic telephones in your system. If you are using a basic telephone and it does not ring, contact your system administrator.

Accessory Equipment 2-177