B&G Service


Brookes and Gatehouse Service

Frequently Asked Questions

How do I...

Test my Masthead Unit?

Identify my Masthead Unit parts?

Install my paddlewheel?

Identify my system/sensors/parts?

My Depth sounder shows zeros, dashes or flashes numbers that are incorrect:

This fault could either be the in the control unit, (Hecta/Hercules/Hydra/Network/Focus), or the transducer, but statistically it is about 90% more likely to be the transducer or cable. The only practical way to check is by substitution with known working units, either transducer or control unit/depth PCB. The transducer should measure short circuit using a multimeter. All B&G transducers have a unique frequency of 170kHz and you can only use a B&G transducer on a B&G system. All transducers are still available, usually ex stock. Do make sure that the face of the transducer is completely clean. It may have one thin coat of antifouling, but this must be removed each season. Note that high pressure cleaners commonly used to clean fouling from hulls can cause premature transducer failure. If you do not have a substitute transducer available, then you can purchase one from us, or alternatively send your instrument to us for testing.

My Boat Speed has stopped working:

This fault could either be in the control unit (Harrier/Hercules/Hydra/Network/Focus), or the sensor, but statistically it is about 75% more likely to be the sensor or cable. Check that the paddle spins very freely by blowing it. A common complaint is, 'my boat speed works in reverse but not forwards'. This is due to a dirty or worn paddle that needs the power of your propeller to spin it! On an older style Impellor UWU sensor, remove the cable from the back of the unit and measure the resistance of the sensor with a multimeter. It should be between 6-12 kilohms, if not it is faulty. On a Paddlewheel sensor measure the voltage with the black probe of a multimeter on the black wire and the red probe on the red. If this is not 12 Volts (5 Volts for Focus), the control unitis faulty. Now put the red probe on the green wire and turn the paddle very slowly. As the magnet passes the sensor the voltage reading should change from 5 ish volts to 0 volts and back again. If not, the paddle sensor is faulty.