Diver6 User Manual
Section 2: Page 14 of 87
Environmental effects
There may be reasons that the environmental conditions will affect range. For example:
•
If the sea floor is hard packed sand and the water is calm without thermoclines, then the acoustic
conditions will be close to ideal and extended ranges would be expected.
•
If the seafloor is loosely packed marine sediment, the seas rough and significant ambient noise (boat
traffic, oil rig noise, rain etc.) then the lower end of ranges would be expected.
•
If the sea floor is hard rock with a large number of outcrops, then the range may be limited by
multipathing (acoustic signal being reflected off the hard surfaces) or the Diver6 System may have a
clear signal path and achieve extended ranges. It will depend upon the conditions.
•
If the water is a stagnant lake with a severe thermocline, then it is possible that the range may be
limited to very short distances well below the expected range.
Power Setting on the Diver Modem
The transmission power of the Diver Modem controls the volume (how loud) the Diver Modem
transmits. The transmission power from the modem has four settings:
•
Power Setting 8: ~2 W transmission, Transmit Source Level 175 dB
•
Power Setting 7: ~1 W transmission, Transmit Source Level 172 dB
•
Power Setting 6: ~0.5 W transmission, Transmit Source Level 169 dB
•
Power Setting 5: ~0.25 W transmission, Transmit Source Level 166 dB
In general, the higher the power setting is the greater the range. The power setting on the Diver Modem
can be changed “on the fly” in the Diver6 System Software (see Section 5 of this manual). The default
setting for the Diver Modem is Power Setting 6 (0.5 W, 169 dB).
Please note that in order to achieve power level 8 on the Diver Modem, it needs to be immersed in water
in order to achieve backpressure on the ceramic transducer in the modem.