Clear-Com Tempest900 - Manual (Page 57)

51 Tempest®900 2-Channel Wireless Intercom System
2-Wire (Party-Line) Interface
2-Wire party-line intercom systems carry one or two (depending on the system type) channels of full duplex intercom audio, plus
system power and other information on a single XLR-3M cable (2 wires and a ground). Each 2-Wire intercom type has a different
wiring scheme and unique line characteristics. It is imperative to have the rear panel connections and the front panel settings
adjusted correctly for audio to pass correctly between the systems.
Steps to Configure a 2-Wire Intercom Connection
• Adjust the Intercom Type Slide Switches to appropriate manufacturer compatible setting- RTS, Clear-Com, Bal.
• Select 2-Wire connection for the appropriate channels.
• Make the 3-pin XLR physical connections to the Tempest BaseStation and the 2-Wire system.
• Null the system.
• Adjust IN/OUT volume levels between the Tempest Wireless System and the 2-Wire system.
Always confirm that the 2-Wire intercom system is functioning properly before connecting the Tempest Wireless system.
Test each wired communication station before connecting the wireless system. Confirm operation of the wireless system
before connecting to the wired system.
After the slide switch is set correctly, the appropriate channels are set for 2-Wire operation, the XLR cable connections are
made, and power is provided by the 2-Wire system or Master Mode, then audio will pass between Tempest and the wired
system.
Audio may develop an echo that is heard in the wireless BeltStations until the system is nulled. The echo should not prevent
communication but is undesirable. The volume levels into or out from Tempest may need adjusting so that relative volumes
are the same.
Echo Cancellation Menu
In the BaseStation’s Tech Menu is a selection for “Echo Cancellation” (ECAN). This refers to software that assists in removing echo
from 2-Wire intercom connections. Hardware connections need to be optimized with the null procedure to minimize echo in the
physical link so that the software can remove any residual echo.
In the Tech menu, “Echo Cancellation” is “ON” by default, but is only enabled for channels that are selected for operation with a
2-Wire intercom and have a physical connection to a 2-Wire system. See “Nulling” Section of this manual.
If a 2-Wire intercom is never utilized in a system, ECAN can be turned “OFF” to ensure that it cannot create undesirable effects.
This should not be necessary, though, and it is recommended that you keep ECAN “ON” at all times.
ECAN is disabled while the BaseStation’s Auto-Null or Manual Null menu screens are active, to ensure that the hardware is
optimized for echo reduction. When ECAN is enabled, it requires up to 10 seconds of active audio to achieve maximum efficiency.
Brief loud active audio can help accelerate efficiency.