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  #1  
Old 03-26-2018, 02:21 PM
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Quote:
Originally Posted by jr_tech View Post
Do you still measure a high voltage between the chassis and b- ?

jr
No hv neg to chassis I obviously went from b+ to chassis. My mistake.
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  #2  
Old 03-26-2018, 02:49 PM
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What do you hear if you disconnect the grid (pin 2) of the 25L6 audio output tube.

jr
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  #3  
Old 03-26-2018, 03:40 PM
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Originally Posted by jr_tech View Post
What do you hear if you disconnect the grid (pin 2) of the 25L6 audio output tube.

jr
I didn't disconnect anything else but pin 2 of the 6sq7, still humming.
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Old 03-26-2018, 04:17 PM
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I didn't disconnect anything else but pin 2 of the 6sq7, still humming.
So now i'm asking what happens if you repeat the experiment on the next (last) audio stage.

jr
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  #5  
Old 03-26-2018, 04:31 PM
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Well I could take off pin 2 but nothing will happen, heater. Or you meant grid I think ?
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  #6  
Old 03-26-2018, 04:42 PM
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Well I could take off pin 2 but nothing will happen, heater. Or you meant grid I think ?
Yes, grid, pin 5, sorry for the confusion.

jr
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  #7  
Old 03-26-2018, 04:59 PM
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Pin 5 off hum even louder with no hiss as if there was no ant.
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