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XBee transmission under water w/ BS2 — Parallax Forums

XBee transmission under water w/ BS2

WildatheartWildatheart Posts: 195
edited 2010-03-30 21:47 in BASIC Stamp
I'm currently using Parallax RF transmitters and receivers with Basic Stamp 2's to communicate between·a dock and a floating set of controls consisting of various valves.· The·controls are then·connected via umbilicals to a rather substantial submersible.

Does anyone know from knowledge or from testing if the XBee transmission is·effective through water?

It's a salt water enviornment, and the minimum working depth in water·is about 10 feet - but transmission at 50 feet would be better.

Then, if it is effective, will enclosing the XBee in an aluminum enclosure affect transmission?

Thanks Parallax - looking forward to the XBee BS2 carrier board next month.· I'm curious... will it include a voltage regulator?

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-01-18 09:08
    Water is a very poor medium for RF, except at very low frequencies (VLF). Given that the XBee operates at UHF, I wouldn't count on it working under water.

    -Phil
  • kgb_xkgb_x Posts: 8
    edited 2010-01-19 12:13
    Use sound. Radiowaves need very high power and very low frequency to work.
  • Peter KG6LSEPeter KG6LSE Posts: 1,383
    edited 2010-01-20 05:05
    I have Used a NE602 Mixer in the past to send 600 Baud data over a 44.1 KHz sound wave underwater about 10 Feet that was @ 2.5Watts of power ..
    I remember that my few watt (I think it was 3 ) " buddy phone" for scuba diving would go across a full pool ...
    It used SSB ...
    look up OTS they have done some awesome things with UW comms ..

    What kind of data rate do you need .. My guess is 600 baud is plenty for a few valves ...

    Peter KG6LSE

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  • AUV GuyAUV Guy Posts: 1
    edited 2010-03-30 21:47
    Peter, what device did you use for your UW comms? Did you build it yourself? I'm looking for a much quicker solution. I want a cheap (<$100) device to communicate underwater for at least a few feet.

    Everything I find for UW comms is super expensive. Know of anything that's cheap and simple to use?
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