Aspect TDMHA.00, Installation Manual

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Headset Adapter Installation Guide
2.2 Rear View
2.3 Switch Settings
Switch 1 (FREER) is used for factory testing only and must be set to the down position for
normal operation.
The up position will set the unit in a free-run (non clock extract) mode. This is useful for
testing the units without using a DCP. By connecting two of the units together, one in normal
mode and the other in free-run mode, the two units can communicate with each other. The
unit running in normal mode will extract the required synchronizing clocks from the free-
running unit and the two units will remain synchronized.
Headsets connected to the units will then function properly allowing audio communications
between the two corresponding headsets of each unit. For example, the headset connected
headset port # 5 on the normal unit will communicate with the headset connected headset
port # 5 on the free-running unit.
Switch 2 (A - U) is used to select between A-law and u-law compression. In the down
position A-law is selected and in the up position u-law is selected.
Switch 3 (BIAS) is used to select the bias voltage to the headsets. In the down position the
bias voltage is approximately 3.3 volts. This position is only used for headsets requiring
reduced bias voltage to function or for headsets that do not require external power. In the up
position the bias voltage is approximately 9.4 volts. The up position is the default setting for
the currently recommended Plantronics headset/amplifiers.
4-22-2008 3205-10084B Page 5