According to Carl U. the DPP-PSA software is not meant to be used with negative pulses, and some of the
functions that are currently not working may be recovered fixing this issue.

Changed Pulse Polarity in V1730PSD control panel Positive -> Negative 
No changes. Note trigger is currently supplied by external CFD
QLong histograms are still not counting

Set DC offset to 64000. The negative part of the pulse is cut off. Wave histogram shows nothing below zero.
Inversion doe snot appear to be working.


Changed BNC-4 Pulser polarity Negative -> Positive and changed polarity of time signal going to CFD. CFD
triggers OK.
No changes. QLong histograms not counting.

Enabled self-triggering on Ch0 and removed CFD input. DAQ no longer triggers. Put CFD back in.

Changed DC offset of Ch0 to 64010 to remove DC offset. Pulse now looks as attach 1.
Disconnected CFD output -> DAQ does not trigger. Reconnected CFD.
QLong histograms still not counting.

Attempted to change options in V1730PSD control panel one by one to see difference
Enabled Charge Pedestal -> No difference. Disabled
Changed Charge Sensitivity 5 fC -> 5.12 pC. No difference. Back to 5 fC
Changed Discrimination Mode CFD -> LED & removed CFD input. No triggers. Reverted

Changed Baseline Mean 16 -> 1024. Wave changes as per attach 1. QLong histogram starts counting at low channel.
See attach 2.
Changed DC offset 64010 -> 60000. Peak in QLong histogram moves to ~1050 channels. See attach 2.
Changed DC offset back to 64010.
Changed Baseline Mean 1024 -> 64. No changes in either wave shape or QLong peak position.
Changed Baseline Mean 64 -> 256. No changes as above.
Changed Baseline Mean 256->16. Wave is back as per attach 1, QLong no longer counting.