Operating C9

High and Low Voltages:

Please check the following once per shift. In order to see signals, even the "raw" analog pulses, all of the following must be on:

• High Voltages. Fast Trailer Rack 20, the two clearly-labeled grey boxes. Set at +2200V. Note the positive polarity.
• Low Voltages -5.2V and -2.5V, test points and a voltmeter are on the top of the magnet near the staircase.
• Puldown voltages -5.4V across banana plugs on the patch panel, Fast Trailer Rack 1A.
• Verify that ADC cables are still connected (they can fall out). Rack 11 fastbus crate slot 16.

If there is a problem:

• Low voltages -5.2V. The supplies are physically mounted on C9 and are plugged into the yellow interlock-controlled outlet. The first thing to try is to enter the area behind C9, unplug the supplies, and plug them in again. If this does not work then call David W. or Kathy.
• Threshold low voltages -2.5V. The supply is in the fast trailer under rack 1A. Reset it.
• Pulldown voltages -5.4V. The supply is in the fast trailer under rack 1A. Reset it.

Also - beware of another intermittent problem:

The NIM bin in Rack 12 with all the C9 amplifiers has tripped twice already during the 1997 run, resulting in no analog signals. I have taken measures to prevent further occurrences, but there is the possibility of this happening again nonetheless. Check the NIM bin voltages. If any of the voltages are low, cycle the power to the bin.