Re: FYI + Shaper board

[Yves Van Haarlem <yvhaarle@ernest.phys.cmu.edu>]

Hall D Electronics:

Hi Gerard,

What I said (not what i e-mailed) earlier is not correct. Also with 
open inputs I get a baseline between 960-980 channels (also this can be 
changed when initializing the fADCs).

To summarize:

Open connection on the fADC: baseline around 970 ADC channels
CDC+preAmp+shaper on the fADC: baseline around 900 ADC channels

Gerard, did you have time to look to the problem with the differential 
input on the shaper boards? If this is causing the drop in gain, could you 
send a fixed shaper board to CMU? Thanks.

Cheers,
 	Yves

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On Wed, 13 Feb 2008, Gerard Visser wrote:

> Hi Yves,
> 	But, to confirm, when you read out the Struck ADC module with the 
> input open, the resulting baseline is 200. (That's what you said earlier, I'm 
> just looking for confirmation here.) Simon, do you get the same?
>
> 	Gerard
>
> Yves Van Haarlem wrote:
>> Hall D Electronics:
>> 
>> Hi,
>> 
>> The CDC prototype has a maximum of 48 straws that can be read out:
>>
>>         32 parallel oriented + 16 stereo
>> 
>> If the fADC is connected to the CDC via the shaper and preAMP the baseline
>> is around 900 ADC-channels (not 200). This can be changed of course.
>> 
>> 
>> Cheers,
>>         Yves
>>
>>                            /--------------------------------
>>                           /   Yves Van Haarlem
>>         _--~~--_         /
>>       /~/_|  |_\~\      /      Carnegie Mellon University
>>      |____________|    /        Department of Physics
>>      |[][][][][][]|:= /          Wean Hall room 8404
>>    __| __         |__ \          Pittsburgh, PA 15213
>>   |  ||. |   ==   |  | \           USA
>> (|  ||__|   ==   |  |) \
>>   |  |[] []  ==   |  |   \          Tel.:   +1 412 268-6949
>>   |  |____________|  |    \                  +1 412 641-9252
>>   /__\            /__\     \          Fax.: +1 412 681-0648
>>    ~~              ~~       \-----------------------------------
>