Texans don't program themselves, and they don't download their own data, either. To communicate with them boxes called Transcases are used. These cases allow a small computer, called a bridge, to communicate with up to 45 Texans at a time by connecting three Transcases together. 15 Texans are loaded into each case, and then connected to wiring that is part of the Transcase. Various programs are used on the bridge to download data, erase old data, send the event table (the schedule of when to start and stop recording), check the status of the Texans' batteries (each Texan has two D-cell batteries), and perform other maintenance functions. The Texans communicate with the bridges one Texan at a time. Most commands only take a few seconds to go through all 45 Texans, but some functions, such as downloading the data, can take several minutes per Texan to complete.
A trailer was rented for this project as a base of operation for working with the Texans. Unfortunately there was not enough space for all of the Transcases that would have been required to support all 600+ Texans. There was only room for about 400. This meant that there was a lot of extra loading, hooking up, unhooking, and unloading going on in order to get all 600 Texans processed.
When the Texans were finished recording data for the day they would be picked up and brought to the trailer. 400 of them would be loaded into the Transcases and have their data downloaded to the bridges. When 200 of them were finished they would be disconnected from their Transcase, removed, and the remaining 200 new ones would be loaded. Getting all of the data downloaded from the Texans to the bridges usually took 6-7 hours to complete. Once this was finished the data from the bridges was transferred over a local network to three Sun Microsystems server computers. This process was usually started around 1:00am, and would be finished by the time we came back in in the morning.
Before the Texans could be deployed back to the field they needed to be programmed. Programming involved erasing all of the old data from the previous day, sending the event table to the 400 Texans that were still hooked up from the previous night's downloading, and then swapping out and in the remaining 200 Texans. Programming usually took 2-3 hours. The Texans were placed back in the field and left there overnight. Shooting always started in the morning.
Below is a view of the Wasatch Mountains east of the site.
DIRECT LINKS TO PAGES:
ANATOMY OF AN EXPERIMENT
HOW TO DO A SEISMOLOGY EXPERIMENT
600 HEAD OF TEXANS
MORE FUN AND GAMES
ALL GOOD PROJECTS MUST COME TO AN END