R. Savage, S. Karki, T. Shaffer, J. Kissel

At the request of Rick and Sudarshan, I modified the HIGH_FREQ_LINES guardian to start a new long-duration PCAL X excitation sweep to investigate an apparent systematic error they've found at the 5 kHz data point of the previous sweep (see attachment for current status of model vs. measurement, originally from here; the data from previous iterations of the guardian node code in LHO aLOGs 35532 and 35153). 

The new bounds of the sweep are from 4825 Hz, in 75 Hz increments up to 6 kHz, and the sweep direction is *up* instead of down. 

I've committed the changes to the code to userapps repo here,
/opt/rtcds/userapps/release/cal/h1/guardian/HIGH_FREQ_LINES.py

reloaded the guardian code, changed to the start frequency by hand, and ran the INIT to reset the 24 hr timer.

The next observation stretch (after Apr 19 2017 20:25 UTC) should start the sweep and have the frequency set to 4825 Hz.