1. What you're seeing is the GX reading the electrical noise either from the surrounding area or possibly even internally. You might try putting 50 Ohm terminators on the outputs and see if that changes anything. I have no schematics of the unit or any actual knowledge of it's internal workings, but I've been around test gear. Simplified explanation: It probably just keeps increasing the input sensitivity until it reads something. Which, in your case is noise.
2. GX BFB scan with 50 Ohm Coaxial Terminator only.
GX BFB scan with No sample Digitizer and no 50 Ohm Terminator (Open Circuit)
GX BFB Scan with Sample Digitizer connected with Plates fitted and no Bio Sample. These plates are brand new and have never had a bio sample placed in them.
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