Kongsberg EM 2040C, Maintenance Manual

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378511/A
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5 CBMF-CPU link
This test checks the GBit Ethernet interface between the CPU board and
the CBMF board. A large set of known data is transferred from the
CBMF board and the data received is checked by the CPU board.
6 RX-CBMF link
This test checks the GBit Ethernet interface between the RX transducer
unit and the CBMF board. A large set of known data is transferred
from the RX transducer unit to the CBMF board. The data received
is checked by the CBMF board.
7 RX Channels
The Sonar Head has a programmable signal generator board that is used
to inject a test signal at the preamplifier inputs. This test checks all RX
channels. The BIST report lists phase and amplitude response of all RX
channels for 200, 300 and 400 kHz.
8 TX channels via RX
This test checks all TX channels (including the transducers). This
is done by transmitting at one by one TX channel and checking the
received level (through the water) by the receiver unit(s). This test may
require that the water depth is not to large. A warning will be given if
this is the case.
Caution
Do not ping in dry dock. For the EM 2040C this BIST test must not
be run in dry dock.
9 RX Noise Level
This test measures the average isotropic spectral noise level for each
receiver channel (in dB rel 1 μPa/Hz) at three bands: 180 - 220 kHz,
280 - 320 kHz and 360 - 400 kHz
The receiver directivity index, the transducer sensitivity and the filter
bandwidth is used to convert to isotropic spectral noise level. The noise
level should normally be below 50 dB.
10 RX Noise Spectrum
This test measures the isotropic spectral noise level for each receiver
channel as done in the RX noise level test. The noise spectrum level is
displayed for 5 kHz bands for groups of 32 channels. In addition the
average level for all channels are displayed. This spectrum test can be
used to search for external noise sources.
Troubleshooting