IU QuarkNet meetings

Friday, March 9, 2001

Meeting Place-Rick's office

Meeting time 3:30 PM

Attendance: Rick Van Kooten; Dave Blair; Matthew Hitchings, and Paul Smith, Electronic Engineer with the Light Quark Group

Note: See Paul's web site for pictures of the PT and bases developed at IU with Paul as the corresponding author—these are the ones that the Light Quark Group are giving to us for the project –Click on "Photomultiplier Bases" in Paul's page. Check out the other things that he provides as well.

http://dustbunny.physics.indiana.edu/~paul/

Purpose of meeting was to learn more about the PT bases.

• The bases use a 15 volt DC power supply that does not need to be especially clean (cheap supply). The bases come up to 1000 volts automatically, and then need to receive a digital signal to "turn on" and set the proper operating voltage and to provide other commands. We discuss how to set the tubes individually to each's plateau voltage.

Paul showed a box he used in testing to send digital commands to the PT bases. We discussed duplicating his box to control the bases, using an analog signal (which was dismissed because of the modifications needed on the bases), and finally sending a digital signal from the computer through digital outputs on our DAQ boards. This seemed to be the best solution, but did require a more robust DAQ board that what we talked about in our Counting Cosmics proposal. We returned to Rick's office to look into the DAQ boards, and found what we think will work. Rick will correspond to make sure that different digital ports can operate either as input or output. He also will establish what software we will need. The boards have Labview drivers, and the University already has labview software, but the company also sells a different software product that may suit our needs better.

• We discussed the type of ribbon cable needed for the digital signals and that seemed to present no problems.
• We discussed how robust the PT bases are, and arcing may be a problem, especially in humid environments. This may put limitations on outside use.
• Paul gave us copies of the photomultiplier documentation which is at the above reference.

We left about 4:45PM