I believe quite a lot of service provider company has some bad experience with gyrosphere purchase either from Pakistan, Bangladesh, India reseller markets due to gyrosphere receive and tested defective.
Here is one of our way to test gyrosphere , mainboard, encoder, container to ensure system works at sea after delivered to ship.
Please see procedure below :
The result we will know the next day whether the gyrosphere has sway away or maintain at a fix heading ? This method is good because there are times the gyro current is normal below 300mA. But the gyrosphere is unstable and once we install on vessel, it will become disaster.
Happy reading. Do send me enquiry if you find this information useful:-)