Field Notes

<--2010-08-11 11:30:00 | 2010-08-17 09:40:00-->
Other sites visited today: Sherman Island | Sherman Island | Twitchell Rice

Twitchell Rice: 2010-08-11 11:45:00 (DOY 223)
Author: Joe Verfaillie
Others: Jaclyn

Twitchell
8/11/2010

Arrived about 11:45am PDT with Jaclyn. Met Jim. Bruce and Jim are working a new contract building a duck club on Sherman north west of our field. So extra help, Mike, is mostly looking after Twitchell. They have be trouble shooting water levels in Field 1. Water tis a little lower than last week, but still high. Cool, windy with clear skies and sun.

The LGR was in slow flow mode and the CH4/H2O laser was not locked
10:44PST, 28.32C, 12.70Torr, 13.858usec, 1Hz, -1, -1, 521ppm

After a switch to high flow and adjusting the line lock value V0 from 0.195 to 0.205 I finally got the LGR to lock:
10:58PST, 28.45C, 127.52Torr, 13.872usec, 10Hz, 1.8224ppm, 15057ppm, 373.4ppm

I adjusted the pressure with the bypass valve to 145.6Torr. The CH4 ppm seemed more variable than usual. Next week I think I will swap the three-channel LGR with our single-channel LGR.

I put a new program on the CR1000 after swapping cards. The new program should improve the slow 30 minute average file. I tried to read the serial stream from the LI7700 but think I need a null modem to connect the LI7550 directly to the CR1000.

I checked and copied data.

2 photos found

20100811TW_Site.jpg ( 2010-08-11 12:45:10 ) Full size: 3648x2736
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