Hello Patrick,
The digital filters option is mainly used to cut the signal above a certain frequency which disturbs a lot the detector.
This can be very usefull to get rid of LF emitters such a military radio or so.
Without your station up and running this is difficult to give you a better diagnosis.
Note that the noise can be reduced by grounding the controller to i.e. a cold water pipe and by using a clean and "silent" power supply.
The digital filters option is mainly used to cut the signal above a certain frequency which disturbs a lot the detector.
This can be very usefull to get rid of LF emitters such a military radio or so.
Without your station up and running this is difficult to give you a better diagnosis.
Note that the noise can be reduced by grounding the controller to i.e. a cold water pipe and by using a clean and "silent" power supply.