We are trying to bias each system on its own and in sequence biasing each other detector system to see the interdependence.
 

HV OK. TEMP OK. Attachment 1 &2.

9.43 bPlast unbiased, BB7 unbiased. Attachments 3-6 is the noise situation with only AIDA biased (bPlast was biased but turned off after AIDA was biased.)

10/16 FEEs < 20k noise. Max noise is 250k. Downstream AIDA appears to be seeing additional noise since S100.

11:21 Returning after an hour the noise has increased significantly in many channels. Scale changed to 10000 in histograms, it appears that the problem is from a couple hot channels.

11:41 'Power' cycled AIDA turned off. bPlast turned on, on its own, then BB7. bPlast doesn't seem to notice anything.

12:21 bPlast and BB7 on. AIDA ON. Rates and histograms given by attachment 7-8. More FEEs noisy, but same level as 11:21. There appears to be the same noisy channel in all of the FEEs (?) Some grounding not properly accounted for, or a wire touching somewhere (?)

13:55h: AIDA & BB7 on. Rates and histograms given in attachments 9-10. Same level as bplast & AIDA on. Same noisy channels in FEEs. According to Nic, these correspond to the end of the ribbon cables & is normal.

13:59 AIDA, bPlast & BB7 on before lunch. Same levels of noise as in previous combinations (attachments 11-12).

So it seems we can run with the three sub-systems biased simultaneously.