New hardware and software were created to support the solid DT direct heating work

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New hardware and software were created to support
the solid DT direct heating work

• A Cernox RTD thermometer was mounted inside the
  DT cell, 1 mm behind the heater winding, to
  measure heat backflow from the heating coil
  during pulsed direct heating experiments
• High gain, low noise, and pulsed power
  electronics were designed and built to interface
  with the RTD to make short duration (1-100ms)
  temperature measurements, and to provide a
  variable pulsed power source for the direct
  heating coil
• New LabView code was written to perform
  temperature and heater pulse GPIB data
  acquisition

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A linearized bridge circuit was chosen to provide
increased sensitivity (?V/?R), and a linear
output voltage response to RTD resistance changes
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Front Panel of the Temperature Measurement and
Pulsed Heating Electronics
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IC Board Layout for the Temperature Measurement
and Pulsed Heating Electronics
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Individual calibrations were performed for the
Cernox RTD (Kelvins/ohm) and bridge electronics
(ohms/volt)
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These individual calibrations were then combined
to give an overall sensitivity calibration in
Kelvins per volt
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This is a typical temperature profile acquired
during one of our pulsed direct heating
experiments at 18 K
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This is the LabView front panel shown at the
completion of a pulsed direct heating experiment
at 18 K
9
Weve observed solid DT layer brightening 6 ms
after heat pulse initiation, with intensity
peaking at 11 ms