This driver can decode up to four analogue input voltages that are sent to QINSy by a NAVANALOG Analogue to Digital (RS232) converter.

The Driver can decode voltages as raw observations but it can also be used to calculate the current bearing of an "AziPod" thruster by reading 2 analogue signals that represent the cosine and the sine of this bearing.

Driver NavAnalog Analog to Digital Convertor  Interface Type Serial  Driver Class Type Terminated <LF> 
UTC Driver (question) No Input / Output Input  Executable DrvNavAnalog.exe 
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  • Checksum is ignored.
  • For "AziPod" Bearing mode: Driver calculates an output angle between 0 - 360 degrees with hard coded scale factor and offset, presuming signals are interfaced with a 250 Ohms Resistor.
  • Analogue readings in output string are from 0-5000 milliVolts, These are internally converted to 0 to 5.0 Volts.
  • Driver does NOT use any conversions for generic analogue observations. It will decode the input voltage divided by 1000 as found in the string to convert from milliVolts to Volts.
  • Unit id is ignored.


Every Azimuth Pod will provide three 4-20 mA analogue signals:



4mA [-1]

20 mA [+1]



4mA [-1]

20 mA [+1]



4mA[-160 Hz]

20 mA [+160 Hz]

These signals should be connected through a 250 Ohms 0.1% resistor to convert from Current to Voltage resulting in: 4mA - 1.0 Volts and 20mA - 5Volt.


Input range of NavAnalog units is by default 0-5 Volts.

Add a "Surface Navigation System", select system "NavAnalog Analog to Digital converter" and add up to four observations of any type.

Generic applications:

Correct Scale Factor and Fixed C-O must be entered in DbSetup in order to convert to the correct value in other QINSy modules.

Set the first slot number to indicate the channel of the A/D converter so fill in "1" for channel 1 etc. up to 4.

Set the second slot number to "0", this implicates it is a generic analogue observation. If the second slot number is not equal to zero, the driver will decode and process the analogue readings as an "AziPod" bearing.

For AziPod Bearing:

Select Observation of type "True Bearing" , Select "At Node" the node of the Thruster. Select for "To Node" any node you like (the "To Node" is not used). Select Degrees for units. Scale Factor and C-O's can be given any value one finds appropriate.  The field number in the input string for the Sine of the angle should be entered in slot1 (1..4). The field number in the input string for the Cosine of the angle should be entered in slot2 (1..4).

Example of setting up the scale factor and C-O:
RPMs should be +160 when 5.0 Volts is decoded, -160 when 1.0 Volts is decoded.
Scale Factor = 320 / 4 = 80.0
C- O =  Obscalc / SF - Obsraw = 160 / 80 - 5.0 = -3.0.