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User Manual
Rev. 1.0 - 27/10/06
TEX500-LCD & TEX1000LIGHT
8.3 Panel board - CPU (SL007PC2001A)
The panel board accommodates the microcontroller that runs equipment firmware
and all user interface elements (display, LEDs, keys, …).
This board is interfaced with other equipment modules via flat cables and provides
for power supply, control signals and measurement distribution.
8.4 Main Board (SLMBDTEXLC06)
The main board performs the following tasks:
• Audio and SCA input processing;
• Carrier generation;
• Modulation.
Both measurements are adequately processed and sent to the interface board
that controls the protection modules and relays the signals to the CPU board to
enable readings to be displayed.
8.4.1 Audio input section
The audio input section accommodates the circuitry that performs the following
tasks:
• Input impedance selection
• 15 kHz filtering for R and L channels
• Stereophonic coding
• Preemphasis
• Mono, MPX and SCA channel mixing
• Clipper (limits modulating signal level so that frequency deviation never exceeds
75kHz)
• Modulating signal measurement.
8.4.2 PLL/VCO section
This section of the board generates the modulated radiofrequency signal. It is
based on a PLL architecture that includes an MB15E06 integrated circuit.
8.5 Driver Board (SLDRVTEX1KL)
This section accommodates a BFG35 transistor that preamplifies the RF signal
before it is relayed to the final power amplifier. When the exciter is placed into
stand-by mode, the driver is inhibited, too.
