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Vintage threads from the first ten years
| previous: Stephen Delft Hi Mike, |
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Re: Cathode Bias Idling Current
 12/26/1997 9:35 AM |
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Mike T | Re: Cathode Bias Idling Current Hi Stephen, Good to hear from you. How are things in NZ? Things are OK here, they've stabalized a bit, although my New Years Eve gig just got cancelled for lack of ticket sales. Bummer. Anyway, you did understand my question, but let me try and give you specifics as to what I need to know, and see if I understand you correctly. I'm building an amp that I want to bias into Class A. I have obtained a 300-0-300 250 mA PT and a 4300 ohm primary 60watt OT, and I want to use it with either (2) EL34s or (2) 5881s. I burned out the part of my DMM that reads current, so i have to find another means short of buying another DMM. EL34s have a max current of about 150mA, so I would need to bias them at about 75mA per tube. If I were to use a 250ohm rK, and read the cathode voltage at 35 volts, that would be interpreted to be (25/250)/2 = 70mA per tube, right? Thanks. Mike Tremante |
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| Stephen Yes...you have a small typo there, ... -- 12/26/1997 7:59 PM Steve A. Mike: |