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Old 29th October 2010, 07:01 PM   #61
240z4u is offline 240z4u  United States
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DF96, thank you for the explanation. The transformer I am using for the heaters does not have a center-tap.

I think I am seeing the error of my ways here. My circuit goes like this; Transformer with no center tap through resistor (to lower voltage) to tube on the left, and tube on the right (connected in paralell as you suggested).

I grounded the heater center tap on both tubes to the same location. Sounds like what I did is redundant and can cause hum.

Thanks so much.
Yeah... it seemed like a good idea at the time.
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