Valcom PagePac Plus AmpliCenter Series Installation And Use Manual page 11

Connectivity Definitions
The Dry Loop 600 Ohm is a four wire interface consisting of a dry audio pair 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 Cl
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 T/R
more sensitive. Adjust by experimentation to account for various line loss and noise. This feature is beneficial for (Ampli-
fied) microphone sources that don't have a Music/Page control contact or for Page Audio from Page Port without a
control contact closure pair.
Dry Loop Hi Impedance is used to interface with parallel multiple Amplicenters. Input impedance is 10K Ohms. Other-
wise, the same as the 600 Ohm dry loop operation.
The Ground Start mode is a two wire interface and has a 600 Ohm input impedance. When a trunk is accessed, a
momentary ground is sent to the ringside of the pair by the host equipment, loop current is detected and the tip-side of
the pair is closed. Disconnect supervision of the ground start mode is accomplished by monitoring the loop current.
Note: Ground start interface requires common ground between Amplicenter and telephone system by direct line or other
common grounding methods.
The Loop Start mode is two wire interface and has a 600 Ohm input impedance. The host equipment draws loop current
from the talk battery which is supplied by the AmpliCenter. Disconnect supervision of the loop start mode is accomplished
by monitoring the loop current.
TECHNICAL ASSISTANCE
When calling, have a VOM and a telephone test set available and call from the job site. Call (540) 563-2000 and press 1
for PagePac Technical Support or visit our websites at http://www.pagepac.com and www.valcom.com.
Should repairs be necessary, attach a tag to the unit clearly stating company name, address, phone number, contact
person and the nature of the problem.
Send the unit to:
Valcom, Inc.
®
PagePac Repair Dept.
5614 Hollins Road
Roanoke, VA 24019-5056
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