R1 S6 SignalSearchLog
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Things that may cause "noise" that are actually due to your testing setup:
- STB boards not securely attached to chamber. Make sure center screws (ones attaching directly to the chamber, not the nylon stand-offs) are tightened to 14 in. lb's.
- Scope's termination set to 1Mohm. Set the scope to 50ohm termination.
- Lower bandwidth of 1 Ghz scope to 200 Mhz. This attenuates peak height, but also rejects high frequency noise and reduces the noise level from 55-65 mV to ~11-15 mV.
- Extra movement a vibrations in the amplifier.
Super Layer 1
|U1||This channel presents higher noise level than the other ones, which makes difficult to get a signal with amplitude below 30mV. This behaviour extends to all the first channels of each connector in the board. however, if a high enough trigger level is set in the scope(~40mV), it is always possible to get a signal in these channels.|
|U24||Warm Wire: This is a channel that always triggers a fake signal.|
|U66||HOT Wire: This is a channel that always triggers a fake signal very often.|
The rest of channels not mention here has a similar behaviour between them, with a noise level not greater than ~20mV.
|U15,U21,U28||This Board presents a unusual noise in all the channels. The noise is a big positive spark, which makes difficult the recolection of signals. However, It was possible by setting a higher trigger level in the scope.|
|U61||Hot and Noisy. The Cause of the noise is the amplifier used. It turns out that this device is very sensitive to the vibration and movement.|
|U08||Hot and Noisy.|
Super Layer 2