Testing procedure
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.
Super Layer 1
STB-1 G1202220
Layer |
Wire |
Channel |
Date |
Comments
|
|
|
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.
|
|
|
U38 |
|
Warm Wire
|
|
|
U66 |
|
HOT Wire: This is a channel that always triggers a fake signal very often.
|
|
|
U87 |
|
HOT Wire: This is a channel that always triggers a fake signal very often.
|
|
|
U93 |
|
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.
STB-2
STB-3
STB-4
STB-5
STB-6
STB-7
Super Layer 2
STB-1
STB-2
STB-3
STB-4
STB-5
STB-6
STB-7
CLAS12_R1_S6_QA