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Troubleshooting & Checkout
DSP Modules
The DSP-8200d signal processing modules require no adjustments or calibration. All
signal processing functions are performed within the DSP processor.
The tone suppression and noise reduction modes of the DSP-8200d do not easily
lend themselves to traditional measurement techniques. These algorithms have been
designed for human speech and interfering noise or tones. As such, these algorithms
modify themselves dynamically with changing speech or noise conditions.
The easiest method to verify correct operation of a DSP-8200d module is to reconfigure
the mode to bandpass. Since all signal processing functions are performed exclusively
by mathematical calculation, a DSP-8200d module that passes this test will also operate
correctly in the other operating modes.
WARNING:
THIS PROCEDURE SHOULD NEVER BE PERFORMED IN AN
OPERATING COMMUNICATION CHANNEL!
IT IS INTENDED FOR OUT-OF-CIRCUIT TESTING ONLY.
TEST TONES WILL PASS THROUGH THE DSP
MODULE IN THIS TEST!!
Test Procedure - DSP Module
1. Remove the DSP module from the card cage and reconfigure the mode to bandpass.
2. Reinstall the DSP module in an off-line, unpowered DSP-8200d card cage.
3. Apply a signal to the input of each DSP channel. The signal should be passively
bypassed by a mechanical relay and therefore identical at the output of each
channel. If this test fails, it is an indication of a bad relay on the DSP module or a
connector/cabling problem.
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