====== Magnetic Fields I: $e/m$ of electrons ======
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==== Common area ====

  * Magnets (can be used to divert the beam if there is a dead spot on the CRT screen)
  * "Exposed" CRT, //if available// (can be used to show the inside workings, especially the deflection plates)
  * Extra spare parts, especially the following:
    * Multimeters
    * 500 V power supplies
    * 50 V/2 A power supplies
    * CRT
  * Fuse repair kit, including the following:
    * Extra batteries (AAA)
    * Extra fuses (500 mA or 630 mA)
    * Philips screwdriver (medium-size)
    * Flathead screwdriver (small-size)

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Also, set up one $e/m$ "demo" using the old setup.
  * e/m apparatus
  * 500 V power supply
  * Battery eliminator (6 A supply)

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Wire the demo and leave connected between labs.
  * The accelerator voltage can be supplied by only the B+ (0-400 V) supply and needs to be connected via "com" and "+" jacks.
  * Set the battery eliminator voltage limit (bottom knob) to be between 6 and 9 V, and use the current adjust(upper knob) to change the current to the coils.
  * Tube takes 30-60 seconds to warm up when first turned on.

==== Individual station ====

  * CRT
  * C-clamp
  * 500 V power supply
  * 50 V/2 A power supply
  * 2 multimeters

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On the 50 V/2A power supplies...
  * ...turn the current limit up to max (2 A), and
  * ...check the overload button (and reset if necessary).

Check the multimeters to make sure there aren't blown 500 mA fuses.