AT&T PagePac Plus, Installation And Use Manual

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The Dry Loop 600 ohm is a four wire interface consisting of a dry input
with a 600 ohm impedance and a control pair. The page input is activated
when the control pair receives a contact closure from the host equipment,
connecting C1 to ground. The Dry Loop page input can also be activated
by the presence of Page Input audio signals that exceed a set threshold.
This threshold is set by the Page VOX adjustment; clockwise rotation
lowers the threshold and makes it more sensitive. Adjust by
experimentation to account for various line loss and noise. This feature is
beneficial for (amplified) microphone sources that don’t have a Music/Page
control contact, or for Remote Amplicenters connected by leased pairs so
that another pair is not required for Music/Page switching control.
The Dry Loop Hi Impedance is used to interface with parallel multiple
inputs. Input impedance is 100K ohms, otherwise, the same as 600 ohm
dry loop operation.
The Ground Start mode is a two wire interface with the talk battery being
supplied by the PagePac Plus controller unit and has a 600 ohm input
impedance. When a trunk is accessed, a momentary ground is sent to the
ring-side of the pair by the host equipment, loop current is detected and
the tip-side pair is closed. Disconnect supervision of the ground start
mode is accomplished by monitoring the loop current.
The Loop Start mode is two wire interface with the talk battery being
supplied by the PagePac Plus controller unit and has a 600 ohm input
impedance. Disconnect supervision of the loop start mode is
accomplished by monitoring the loop current.
Connector
The page input cord that connects the telephone system to the PagePac
Plus has a standard 4-wire RJ-11 type connector. The other end of the
cord, depending on the host system, may have a special 25-pair
connector, spade-tip leads, or an RJ-11 type plug.
The page input cord conductors are usually color-coded and are
connected to the host system as follows.
1. Connect black wire to the paired dry contact control lead ground.
2. Connect yellow wire to the paired dry contact control lead C1.
3. Connect red wire to system ring R.
4. Connect green wire to system tip T.
Installing the Hardware
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