Just to be sure, you are saying wire the two 330V secondaries in series , not parallel, and common point between two taken to ground.Do this and you should have no hum. Your 6.3V secondaries aren't strong enough and you parallel those I suppose.
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buzz
one 6V3 winding is directly connected across 5U4's 5V heater !
does just one 6V3 winding have enough current for heating 5U4?
I have both 6.3V secondaries in parallel to rectifier. Should be 6A. Antek generally under spec's their trafos, so even one should do, rated at 3A; although working too hard i would imagine.
I just saw what Salas wrote about weak windings ........
you canconnect them in parallel , but!! securing that each 6V3 winding have own fixed resistor ;
so determine those resistors by trial and correct , going from higher value , that way that they're paralleled at tube heater
than take your Ub from whatever side of rectifier tube's cathode , as Salas posted
you canconnect them in parallel , but!! securing that each 6V3 winding have own fixed resistor ;
so determine those resistors by trial and correct , going from higher value , that way that they're paralleled at tube heater
than take your Ub from whatever side of rectifier tube's cathode , as Salas posted
I just saw what Salas wrote about weak windings ........
you canconnect them in parallel , but!! securing that each 6V3 winding have own fixed resistor ;
so determine those resistors by trial and correct , going from higher value , that way that they're paralleled at tube heater
than take your Ub from whatever side of rectifier tube's cathode , as Salas posted
THe resistors before parallel point being an attempt to balance draw and reduce hum, as hum is essentially a difference or imbalance in voltage?
THe resistors before parallel point being an attempt to balance draw and reduce hum, as hum is essentially a difference or imbalance in voltage?
even if that you have hum there (in heater circuit of rect. ) and you have it anyway - because you are heating it with 5V/60Hz hum in fact .... fact is that that hum is floating , referencing to your audio power circuit
......
Exactly!. Actually, my secondaries are rated for 4A, so I think Salas is right that one can be eliminated, leaving the balancing act for another day. I ahev read that unused secondaries should be connected through a resistor to ground to prevent buildup. Am i delusional or is this something that is done?
even if that you have hum there (in heater circuit of rect. ) and you have it anyway - because you are heating it with 5V/60Hz hum in fact .... fact is that that hum is floating , referencing to your audio power circuit
Never thought about it like that.
Exactly!. Actually, my secondaries are rated for 4A, so I think Salas is right that one can be eliminated, leaving the balancing act for another day....
if they're 4A , then OK
........ I ahev read that unused secondaries should be connected through a resistor to ground to prevent buildup. Am i delusional or is this something that is done?
no
just isolate ends
just another web legend , at least in this case
even in digital world , fully open unconnected winding is - nonexistent
Never thought about it like that.
just another proof that Ground is state of mind
it can be whatever you choose , and execute correctly
Filament went bad on soldering iron. Just got cheapo radio shack to make changes. Changing to single secondary to filament made no changes in hum. Hoping the CT configuration on B+ secondaries makes a difference. Let you know in a bit, and thanks for asking. Its been a day from hell so I need something to work!
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