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Re: Preamp & Interposer
Hi Fernando,
Very nice that you found the problems. I guess the bad solder joints were
good when I got the interposer and became bad after a while - I am not so
worried about that. But channel 16 on the preAmplifier died at some point
- you can see it dying (on March 6, 2008) in the data. As far as I
remember we did not do anyting to the pre-Amplifier on that day but it is
already a month ago. Maybe you have an idea what could have damaged the
pre-amplifier because it should be avoided in the future.
Cheers,
Yves
/--------------------------------
/ Yves Van Haarlem
_--~~--_ /
/~/_| |_\~\ / Carnegie Mellon University
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__| __ |__ \ Pittsburgh, PA 15213
| ||. | == | | \ USA
(| ||__| == | |) \
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On Wed, 9 Apr 2008, Fernando J. Barbosa wrote:
> Hi Yves,
>
> I verified that the interposer had some bad solder joints and these have been
> fixed. The one you have should be good.
>
> I checked the amplifier and indeed channel 16 was not working. Further tests
> revealed that the ASIC A input (for negative going signals or anodes) has
> been damaged. The B input (for positive going signals or cathodes) works
> fine.
>
> Because I don't have additional preamp cards, I suggest that Gerard send you
> his preamp and I will send him yours, which he can use for his tests. I will
> ask Elke for additional funds to produce a few more preamp cards (we have a
> few ASICs left).
>
> Gerard, let us know if if this works for you.
>
> Regards,
> Fernando
>