Sheila and I spent some time today trying to calibrate the PMC channels into units of frequency so we can compare the glitches seen by the PMC with other channels. Peter's alog comment last night (81375) leads us to understand the glitches are around 2 kHz in frequency, so above the PMC bandwidth. Therefore, we want to calibrate the PMC error signal.
Luckily for us, Jeff Kissel recently did some PMC scans to determine the PMC PZT Hz/V calibration for a different purpose, alog 73905 (thanks Jeff!). We used his DTTs to determine the time it took to scan one FSR, see screenshot. We determined that it took 0.52 seconds to scan one FSR, and the scan rate is approximately 6.75 V/s (we know the PZT is nonlinear, but we figure this estimate is good enough for our purposes). This gives us 3.51 V/FSR on the PZT, or 0.0236 V/MHz, using the FSR = 148.532 MHz from T0900616.
We are still thinking about how to calibrate the PMC mixer signal.
Daniel calibrated the PMC mixer signal using the PMC PDH signal, lho81390.
H1:PSL-PMC_MIXER_OUT_DQ calibration is 1.25 Vpp / 1.19 MHz (fwhm) = 1.05 V / MHz.
See his note about H1:PSL-PMC_MIXER_OUT_DQ: "the channel recorded by the DAQ has a lot of gain and clips around +/-80mV, but it is calibrated correctly" compared to live traces on an oscilloscope.