We took data at different currents and gain with the HARP. I think we are concluding that the signal of harp IH05A is too small to be seen at 3 uA and in 1H04 the signal gets comparable to the electronic noise. So we will run HARP scans at 5 uA minimum most of the time to the maximum value available which is 8 uA.
We will put back the preamplifer on 1H05A since the previous preamplifier had less DC offset giving more range to amplify and since the problem was current.