Sheila, Jim

We had some issues with one of the PI modes tonight. Mode 26 rang up and took some careful wrangling to get damped back down. The first issue we found was that the BP and PLL frequency were both off, so we selected the 15009hz (FM1) and tuned the PLL frequency appropriately. However, the mode was still unresponsive to the normal phase tweaking and broke the first lock. When we got back up,  we missed waiting at DC readout for the PI to settle back down, so we ended up having to damp 2 or 3 modes simultaneously. Fortunately everyone but mode 26 were easy customers. Mode 26 required careful tweaking of the phase and Sheila eventually increased the gain to 15000 from 4000. The mode was also kind of slow to respond so zooming in on the rms strip tool helped differentiating good from bad phase tweaks.