Simrad SC90, Installation Manual

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419050/B
353
f Set
Sample range
to 1000 .
These settings allow you to test the transmitter performance.
7 Look at the pattern in the B-Scan presentation, and compare them with the example
provided.
8 Do these changes:
a Set
Start sample
to 1500 .
b Set
Sample range
to 10,000 .
These settings allow you to test the receiver performance.
The sample frequency in the SC90 is 5 kHz. Since the sound travels approximately
750 meter back and forth every second, each sample will cover 750 m divided by
5000 Hz, which is approximately 15 cm. These settings will thus allow you to test
the receiver in the near range between 0 and 150 meters from the transducer.
9 Look at the pattern in the B-Scan presentation, and compare them with the example
provided.
• If a single element is "dead" (no transmit, no receive), the rectangle is easily
spotted because its colour is black.
• If a single element is receiving, but not transmitting, the rectangle is normally
presented in lighter shades of blue.
• If a transceiver board is "dead" (no transmit, no receive), all the transducer
elements connected to the board are easily spotted because they are all black.
10 Check for any weak elements in the transmission sample range.
If any weak elements are detected, record these in the result table.
11 Check for any black lines in the transmission and reception sample ranges.
A black line would indicate an unserviceable element. If any such elements are
detected, record these in the result table.
12 Hoist the transducer back up to its upper position.
Result
Requirements Results
The information presented by the
B-Scan
page verifies that the SC90 is
fully operational.
All elements are operational in both transmit and receive. The maximum
number of unserviceable elements is 5.
Weak elements:
Unserviceable elements:
Date and signature:
Setting to work