# Instrumentation & Calibration

**URL:** https://discourse.ocean-acoustics.org/c/instrumentation-calibration/8.md

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## [About the Instrumentation & Calibration category](https://discourse.ocean-acoustics.org/t/about-the-instrumentation-calibration-category/14)

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**Author:** [@leewujung](https://discourse.ocean-acoustics.org/u/leewujung)\
**Replies:** 0

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## [Portable X-ray for swimbladder analysis at sea](https://discourse.ocean-acoustics.org/t/portable-x-ray-for-swimbladder-analysis-at-sea/147)

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**Author:** [@alejandro-ariza](https://discourse.ocean-acoustics.org/u/alejandro-ariza)\
**Replies:** 6\
**Last updated:** [October 2, 2025, 8:10am UTC](https://discourse.ocean-acoustics.org/t/portable-x-ray-for-swimbladder-analysis-at-sea/147 "2025-10-02T08:10:08Z")

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Hi, I’m looking into whether there are portable X-ray devices that would allow us to detect and measure the swimbladder of fish during surveys at sea. I’m completely inexperienced in this area and was wondering if an…

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## [Calibration on large boats with difficult access to bow](https://discourse.ocean-acoustics.org/t/calibration-on-large-boats-with-difficult-access-to-bow/125)

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**Author:** [@fernandespg](https://discourse.ocean-acoustics.org/u/fernandespg)\
**Replies:** 2\
**Last updated:** [September 2, 2025, 8:29am UTC](https://discourse.ocean-acoustics.org/t/calibration-on-large-boats-with-difficult-access-to-bow/125 "2025-09-02T08:29:28Z")

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Calibration of active sonars requires a small sphere(s) to be suspended some distance below the transducers, which are often mounted on the keel, forward of the centre of the vessel. On large vessels this poses challeng…

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## [Open-echo: open hardware and open source echosounding](https://discourse.ocean-acoustics.org/t/open-echo-open-hardware-and-open-source-echosounding/96)

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**Author:** [@Sven](https://discourse.ocean-acoustics.org/u/Sven)\
**Replies:** 1\
**Last updated:** [April 25, 2025, 8:13pm UTC](https://discourse.ocean-acoustics.org/t/open-echo-open-hardware-and-open-source-echosounding/96 "2025-04-25T20:13:38Z")

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this is a pretty cool open hardware and open source echosunder project. Still in development but pretty interesting at least: https://github.com/Neumi/open\_echo tesing video some more info copied from the Github: An…