Difference between revisions of "Water depth - echo sounder (Fahrentholz)"
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m (Water depth - echo sound (Farentholz) moved to Water depth - echo sounder (Fahrentholz): typos in title) |
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*may sometimes loose calibration and require resetting (press button and the device is back in seconds) | *may sometimes loose calibration and require resetting (press button and the device is back in seconds) | ||
*when attached to the stern, bubbles in the wake may produce noisy signal | *when attached to the stern, bubbles in the wake may produce noisy signal | ||
| − | *when used with (d)GPS, synchronize system time of laptop with GPS time. BEWARE: true GPS-time is 15 sec ahead of UTC (Nov 2010), which increases every 8 month due to leap seconds. Check | + | *when used with (d)GPS, synchronize system time of laptop with GPS time. BEWARE: true GPS-time is 15 sec ahead of UTC (Nov 2010), which increases every 8 month due to leap seconds. Check which one the GPS ''displays'' and which one it ''records'' (this may differ!). |
==Problems/Questions:== | ==Problems/Questions:== | ||
Revision as of 14:15, 9 July 2015
Parameter to be measured:
Water depth (subsurface measurement)
Method:
echo sounder (sonar)
Equipment:
Fahrentholz BBES 30/ 100 /200 /700
Advantages:
- no-frills sturdy device
- simple recording with any COM-port monitor (e.g. Telnet, Hyperterminal)
- up to 40 measurements/sec from 0.1 to 100 m
- custom modifications on request
- can be used in conjunction with (d)GPS, synchronize both records via timestamp (see scripts below)
- rustic bulky Landrover-style
Disadvantages:
- computer connection needed, no internal logging
- COM-port needed
- external 12/24 V battery needed
- no logging software provided (see scripts below)
- no real-time display of values
What to watch out for:
- may sometimes loose calibration and require resetting (press button and the device is back in seconds)
- when attached to the stern, bubbles in the wake may produce noisy signal
- when used with (d)GPS, synchronize system time of laptop with GPS time. BEWARE: true GPS-time is 15 sec ahead of UTC (Nov 2010), which increases every 8 month due to leap seconds. Check which one the GPS displays and which one it records (this may differ!).
Problems/Questions:
Price:
~ 2500 € (2003, Germany)
Links
Projects that used the above equipment:
Other related web sites:
[[ http://www.fahrentholz.de/bbesneu.htm ]]
(Python script - to be uploaded soon -)