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  • The flames from a gas filled tube make a standing wave pattern as a speaker broadcasts tones to a diaphragm on one end.
  • Open valve to 5 o'clock position, then light the tube by running a match along the row of holes on top.
  • Fundamental frequency is ~140 Hz
  • CAUTION: propane gas is heavier than air and tends to pool in low areas. Keep flame tame to avoid setting off fire alarm.
  • There is a fire extinguisher in the cart.  Use of safety glasses is recommended.
        (close all valves during transport)
        (tighten hose clamp finger tight, check for leaks with compressed air)
        (after first use, take tube outside, blow 10 breaths into hose, take inside,
          connect to compressed air for 1 min. with holes down)
        (after last use, take tube outside, remove diaphragm, blow into hose to
          remove propane)
        (store diaphragm in plastic bag)

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