> I have an eight FEE64 system now in place on the LYCCA chamber with a PB-5 pulser going into the adapter cards 
> test input. The test capacitor is 30pF.
> 
> I was going to explore the effect of the thresholds on the pulser peak.
> 
> I notice that the spectra look like those taken in RIKEN and not a single peak. In the 1GeV range I would 
> interpret this as noise but since this is such a high energy i don't quite understand what is happening in the 
> ASIC.
> 
> I thought i would share it with you.
> 
> PB-5 input to 50R is 10v with no attenuation. Signal height on the inline 'scope is +5.2v
> 
> ASICs are set to "default" with 1GeV range and 3uS shaping time.
> 
> Let me know if anything useful can be gleaned by more tests on LYCCA.
> 
> 
> 
> Q = CV = 30pF * 5V = 150pC => ~ 3.42GeV => ADC channel ~ 27880
> 
> The spectra imply a positive test input. The spectra imply an inconsistency between the data
> supplied and the peak position.
> 
> You display the spectra on a log scale ...  so the majority of events are in the peak ... but
> why do some channels so a peak and others a peak plus a small number of higher amplitude/events?
> 
> What ASIC settings are you using?
> 
> What is the PB-5 frequency? ... PB-5 settings?

PB-5 is at 100Hz, fall time is 1 ms. 
ASIC settings default from VHDL.
They are in the manual. See EDOC955 at npg.dl.ac.uk

29300 => 2.1GeV ( very approx )  so yes this doesn't make sense. 
Hard to have a specific calibration or will your beam time give that.

I think the 30pF is correct but i can measure it on Wednesday......