Guardian Telecom Inc.
Installation & Operation
TBA Models
The connections for the TBA-33 PWBAs starting in 2012 are shown below. Note that the value of R161
is 10 K Ohm and R166 is 1.0 K Ohm to reduce the input gain to telephone line levels. The transformer
on the Central Station output is a 600 to 10K Ohm transformer to raise the impedance from 8 Ohms to
150 Ohms in order to be closer to the impedance of a microphone input to a telephone line adaptor
module.
Figure 10 - TBA-33 Internal Audio Connections Starting 2012
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