we measued the OLTF of the PMC loop. Fig.1 shows the TF.

According to the circuit diagram of the TTFSS servo (JGWdoc), the gain from OUT1 to OUT2 is ~10 dB (=20*log10(392/124)). So actual UGF is the frequency where the measured gain is -10dB in the fig.1, that is ~2. kHz. This is consistent with the value the previous NeoLASE high power laser in klog22620.