Information regarding the B and G (brookes and gatehouse) sensors for the H2000 and the H3000 systems.

213 MHU

This is the standard Masthead Unit for the BandG H2000 and H3000 systems, you can change/replace the bearings of the windvane and wind cups. The bearings are according to the English (imperial) system. Read this article for info on the replacement of the 213 and 496 MHU.

Or in case of a hardware failure, remove the PCB:
If you want to repair the PCB, read this:
for some tips on replacing the FETS (BF256A) and recalibrating the unit

For the wiring and the connector read this document:


The clinometer (690-00-004) used by B&G seems to be linear in it's output, here is a table with some raw measurements:

 H 44 2.17 volt   heel port 
 0 3.15 volt   neutral (no heel)
 19.5 H 3.55 volt  heel starboard
 44.1 H 4.09 volt   heel starboard
 51.0 H 4.24 volt  heel starboard

Maximum heel value displayed on the displays is around 60 degrees

The measured linear function seems to be:
heel angle = 46 * volts - 144.12 (with some offset on calibration)

So it seems like the heel angle covers 300 degrees of tilt (+/- 150 degrees), so the correct function seems to be:
heel angle = 46.154 * volts - 150

Trim should be the same. Using a clinometer improves the measurements to the Apparent Wind Angle (AWA)
Building a custom Heel and Trim sensor is quite easy, use a sensor (e.g. Memsic MX2125) and an Arduino Atmega to process the pulses and output a voltage into the B&G main processor. Should work with H3000 also. Cost about 50 euro for heel and trim (compared to 2x 800 euros for official B&G)
The formula is: outValHeel = pulseX*0.056-116.43;
For H3000, add a Capacitor for an RC filter.

Temperature sensors

Sea temperature Part no: 224-00-065
Standard NTC 10K

Air temperature part no: 224-00-066

1,20 volt = -8,6 degrees C
2.00 volt =  2,6 degrees C
3.00 volt = 17,1 degrees C
3,25 volt = 20,5 degrees C
4.00 volt = 31,1 degrees C
5.00 volt = 45,3 degrees C
This also seems like a standard NTC 10K temperature sensor connected to 6.5 volt, and a 11.6K? ohm resistor to ground.
6.5 volt pin
                             10K NTC
measurement pin
                             11.6K resistor?
gnd pin

Barometer sensor

Barometer part number: 690-00-007
2,004 volt =  909 mbar
2,100 volt =  918 mbar
2,504 volt =  938 mbar
3,001 volt =  967 mbar
3,503 volt = 1002 mbar
4,010 volt = 1034 mbar
4,504 volt = 1066 mbar
5,001 volt = 1099 mbar

This is a linear line, approximate formula:
mbar = 63.025* volt + 781.85 
volt = mbar/63.025 - 12.39

Depth meter

Most of them are 170 kHz passive types, including the very old ones and should continue to work.
There should be a 0.5 to 5 ohm resistance between both pins.