Tube warm up time technical measurements

Discussion in 'Portable and Other Gear Measurements' started by atomicbob, Jan 27, 2017.

  1. Aklegal

    Aklegal Friend

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    Received my MJ3 yesterday. I don't have a fancy FLIR thermal camera, just a cheap infrared gun. Mine topped out at 151 degrees after more than two hours of operation. The MJ3 was sitting directly on top of a Audio GD Master 9 with internal heatsinks that reach temps of 120 on its own.

    My rig is in my basement and the ambient Temps this time of year are around 70 degrees.
     
    Last edited: Oct 11, 2023
  2. Vansen

    Vansen Gear Master (retiring)

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    Initially, my MJ3 would reach about 165 degrees on a baby FLIR and Type-K thermocouple. I wasn’t concerned, but was curious due to this conversation. I have been able to get my MJ3 down to 155ºF from 165ºF with a couple of changes. I though I had my MJ3 on a double conversion UPS set at 115 VAC, but when I moved my music setup in September, I needed to do some work on the outlet and a GFCI circuit to make the UPS happy and still had the MJ3 power cord off the wall. I thought it was feeding from the UPS, but nope.

    I suspect the most significant factor is the drop from ~123 VAC to 115 VAC.

    [​IMG]

    At 165 degrees:
    • Mains at 123-126 VAC during the day, 119 to 123 VAC at night.
    • Ambient temperature at 24ºC.
    • Sitting on top of a powered on Rag 1.
    [​IMG]

    At 155 degrees:
    • Mains regulated to 115 VAC with a Vertiv GXT5 double conversion UPS.
    • Ambient temp at 22ºC in this image.
    • Still sitting on top of a powered on Rag1.
      • I might shut if off and post a follow up if the temp is lower.
     
  3. Vansen

    Vansen Gear Master (retiring)

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    I shut off the Rag1 and had the MJ3 on most of the day and was listening to music for an hour before taking this measurement.

    [​IMG]

    At 139ºF (maybe 141):
    • Mains regulated to 115 VAC
    • Ambient temperature at 21ºC
    • Sitting on top of a powered off and cold Rag1
     

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