4 – Operating Procedure
DPN 402197 Issue 7.1
© Teledyne Limited
4- 9
❐
Coil saturation has occurred because the tone signal is too strong
5. Coil altitude (ALT) information comes from an altimeter if the system includes one. Otherwise,
the information in this field will be the fixed coil height if available. Forward Search mode is
available only if information is available concerning the height of the coils above the seabed,
and so this field will always contain information.
6. The signal strengths, in microvolts, measured on channel 1 (starboard lateral – SL), channel 2
(starboard vertical – SV), channel 3 (port lateral – PL), channel 4 (port vertical – PV), channel
5 (starboard fore-aft – SF) and channel 6 (port fore-aft – PF).
Information included in the above signal strength fields may have a very large dynamic range,
extending from less than 1µV to more than 7 volts. To allow for simple encoding of this range, the
system displays and logs values using scientific notation.
7. The QC check code provides additional status information that explains any occurrence of the
QC flag being set. The check code consists of a two-digit number with the meanings defined in
4.5.2 Internal Logging Format
Data packets transmitted by the SEP fall into two categories – ‘co-ordinates’ and ‘signals’. The SEP
transmits them sequentially so that either packet ‘A1’ or ‘A2’ below immediately precedes packet ‘B’.
A1) Co-ordinates Data Packet – Survey mode
The string is 23 characters long with individual field definitions as follows. DeepView logs all distances
in units of centimetres and skew angles in units of degrees. The values in the packet are rounded and
it is possible that they will not precisely match those on the Run Window.
Table 4-5: Internal logging format – Survey co-ordinates
Table 4-4: QC check code meaning – Forward Search mode
QC
Check
Code
Meaning
00
Target in range. SF and PF
50µV; LAT
±2m. Quality flag is RESET.
07
Saturation in one or more coils. Quality flag is SET.
08
Target in range. SF or PF <50µV. Quality flag is SET.
99
Target out of range. FWD = 9999. Quality flag is SET.