Tait TB8100 - Signal Path

46 Functional Description TB8100 Installation and Operation Manual
© Tait Electronics Limited June 2005
4.3 Signal Path
This section details what happens to an audio signal as it passes through the
various processes within a TB8100 BSS, either from the RF input to the
system interface, or from the system interface to the RF output.
Figure 4.10 on page 68 shows the four main components of a single 50W
VHF base station system: the reciter, PA, PMU and control panel.
Figure 4.11 on page 69 and Figure 4.12 on page 70 provide the same
information for UHF systems.
The majority of all Tx/Rx signal processing is performed within the reciter.
All receiver functionality occurs within the reciter while the PA provides RF
amplification of the modulated signal to be transmitted.
The reciter sections of Figure 4.10, Figure 4.11 and Figure 4.12 show the
entire reciter, which is then broken down into the individual digital, RF and
system interface boards. In the digital board, the solid line shows the
functions provided by the DSP (Digital Signal Processor).
Also refer to “Circuit Description” on page 15 for more detailed circuit
descriptions of the individual sub-systems that make up the BSS.
The following sections explain the basic operation of the base station system
by describing the basic signal paths.
Signal
Reciter, PA & PMU
IDC Pin
Standard and Power
Save Control Panel
D-range Pin
Dual Base Station
Control Panel
D-range Pin
I
2
C interrupt 1 (not used) 8 (not used) channel 2 select
I
2
C data 2 15 15
ground (I
2
C) 3 no connection no connection
I
2
C clock 4 7 7
+28V (control panel power) 5 14 14
RS-232 Tx data 6 6 6
ground (control panel power) 7 13 13
RS-232 Rx data 8 5 5
ground (analogue) 9 12 12
control panel speaker 10 4 4
control panel microphone 11 11 11
PSU back-up 12 (not used) 3 (not used) channel 1 select
+24V switched (PA fan) 13 2 2
ground (PA fan) 14 10 10
+24V switched (PMU fan) 15 9 9
ground (PMU fan) 16 1 1