Slightly cooler today with a high of 98F. Early morning there was a light northerly with smoke from an industrial plant drifting down the valley, then the wind switched to southerly with a gust front mid-afternoon kicking up dust. Cloud gradually thickened during the day which provided a welcome respite from the intense sun.
John continued his visit checking on our radar wind profilers. On the 915 MHz wind profiler on MISS, he checked the power output of the amplifier and found that it was a little higher than expected at around 460 W peak instead of the 400 W expected. Out of concern that we might be overdriving the amplifier (which might damage it), he added attenuation to the input. It is now generating about 390W peak power or 56 dBm with 24 dB attenuation on the input.
On the 449 MH Modular Profiler, he and David discovered that the amplifier box required some minor repairs. One of the three amplifiers was disconnected (perhaps having shaken loose in transport) and other similar issues. This meant that the transmit beam was uneven, likely contributing to the low cross-correlations noted yesterday. After repairs, the profiler worked much better. We also checked out radio interference from the profiler on the sounding system and on the 5G wireless network in the REAL trailer. Tests showed that both profilers were not affecting the REAL 5G service. The 449 MHz profiler is affecting the sounding (as expected) so we may need to move the sounding antenna across the access road, although the clutter fence (which we plan to install tomorrow) will likely reduce the interference.
We installed the 3-meter tower just south of MISS with a Lufft WS800-UMB weather sensor and a Campbell CS-125 visibility and present weather sensor.
Checking the power level from the MISS 915 MHz wind profiler (left) and making repairs on the 449 MHz amplifier (right)
Installing a CS-125 visibility sensor (left) and checking interference on the sounding system (right)
A gust front is pictured approaching the site from the south around 2:30pm PDT. We adjusted the windcube lidar scanning strategy to observe the front and saw gusts around 12 - 15 m/s - 27 - 33 mph)