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Re: oscillations
Hall D Electronics:
Hi Gerard,
The scope was set to 50 Ohm input.
Cheers,
Yves
/--------------------------------
/ Yves Van Haarlem
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On Mon, 28 Jan 2008, Gerard Visser wrote:
> Hi Yves,
> Ok thanks for clarifying that. Do you remember also, was the scope
> then set for high-Z or 50 Ohm input? This could make a big difference in
> provoking the oscillations. Let us know, if you remember it. Thanks,
>
> Gerard
>
> Yves Van Haarlem wrote:
>> Hi All,
>>
>> Just to answer Gerard's question:
>>
>>> 2. We put on the new preamp and I asked Yves to connect as before.
>>> Oscillations were observed. Here are the details of the connection: The
>>> signal cable was ~3m, ERNI connector on one end, the other end broken out
>>> to
>>> 100 (?) Ohm termination resistors on pair #1, 2-9, and 18-25. Pairs 10-17
>>> were not terminated. (They are also open on the preamp board end of the
>>> cable, since no ASIC or termination resistor is there.) For one of the
>>> channels (at a time, we looked at a few) the 100 Ohm resistor termination
>>> was
>>> removed (Yves, is that right, or did we leave it?) and in it's place two
>>
>> We left the 100 Ohm termination resistor in.
>>
>> Cheers,
>> Yves
>