Leaving out artificial center tap

Discussion in 'Amp Tech Center' started by Diverted, May 23, 2020.

  1. Diverted

    Diverted Tele-Meister

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    I just built a small Champ 5f2a, finished it up and started playing it. The amp is very quiet with no hum.
    Last night it dawned on me that I did not put an artificial center tap on the heaters.
    Is there any other safety/stability reason to put them in, other than hum control? Because this amp really doesn’t hum! I may leave as is unless I need the artificial tap.

    Also: the 6.3 winding does not have its own designated center tap.
     
    Last edited: May 23, 2020
  2. robrob

    robrob Poster Extraordinaire Ad Free Member

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    The artificial center tap is for hum control so with no hum you're fine.
     
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  3. tubegeek

    tubegeek Tele-Afflicted

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    You may not get the same results with every choice of tubes.
     
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  4. trobbins

    trobbins TDPRI Member

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    The heater has a high resistance to each cathode. Two cathodes are bypassed so their DC voltage won't change much. If you didn't tie one heater side to ground (as per original) then although the heater is floating, it will effectively sit at a few positive volts dc (along with the ACV from the heater winding), so won't cause any stress on the heater-cathode voltage limit.
     
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