PVC/NFOV/M1 - Minor instrument noise

The PVC NFOV data shows the same issue that was present at the PGH deployment.  

When the signals are very low, a regular feature can be seen in the data. It begins on the 
hour, and lasts for ~20 minutes. This feature is a rise in the signal of ~0.25 to ~0.33 
mV. It is small even when compared with the NFOV's typically small signals. My hunch is 
the NFOV is located next to or nearby equipment that operates/broadcasts/etc beginning on 
the hour, and lasting for ~20 minutes. Looking (very closely) back at the previous 
deployment, this regular signal bump is also evident, so it seems the equipment contaminating 
the NFOV is part of the AMF1, and not unique to this deployment.

I struggled as to what color to use for this DQR.  Yellow I think might be the most 
appropriate, but my concern is potential users might choose to disregard the data if it's 
yellow. I decided to go with clear as I do not think the noise would even negligibly affect 
the data.

• Raw counts from instrument before calibration, 673 nm(raw_counts_673nm)
• Calibrated zenith radiance, 870 nm(radiance_870nm)
• Calibrated zenith radiance, 673 nm(radiance_673nm)
• Raw counts from instrument before calibration, 870 nm(raw_counts_870nm)