J. Driggers, S. Dwyer, J. Kissel, E. Merilh, K. Merfeld

After the EQ, we've been having a lot of trouble even getting past the ALS of lock acquistion. We think we might have traced the problem down to the DIFF beatnote (H1:ALS-C_DIFF_A_DEMOD_RFMON) being too low. 
How did we come to this conclusion? A trend of the DIFF beat note over the past many moons revealed that on July 31 / Aug 1 -- when we changed the global alignment -- the trend of the DIFF beatnote consistently dropped from -10 dBm to -25/-26 dBm. Suspecting that 
    (a) this is yet another knock-on effect of the new global alignment position, and 
    (b) that we've just been Aerosmithing our way through life (living on the edge) the past few weeks,
and confirming improvement by adjusting the beam splitter alignment just after an initial alignment (3 urad! in yaw) to regain ~5 dBm of power, we've taken the following actions:

    (1) [After restoring the beam splitter alignment] we've gone out to ISCT1 and adjusted the alignment on to the DIFF beatnote PD.
    (2) Added a check to the ALS_DIFF guardian in the "run" part of its PREPARE state to spew out a notification (sadly only at the ALS_DIFF guardian level) and loaded it. We set the threshold to -26 (dBm).