http://pro-radio.ru/user/uploads/11566.pdf
please scroll till the end of the acrobat doc..
is it required? if so the parts make difference to which stage in specific? VAS or output stage? and what is the role of these R4 and D1
please scroll till the end of the acrobat doc..
is it required? if so the parts make difference to which stage in specific? VAS or output stage? and what is the role of these R4 and D1
yeah preferably for PA use...
but I have a question on power amplification calculations...
like for a psu of 90v the power in load be calculated in with losses of may be 11% p = v^2 / R so here its
6400 x 8 = 800w but the power ratings are rated as 450watts in 8 ohms... Im just doubtful on my calculations can anybody correct me in these psu calculations..
but I have a question on power amplification calculations...
like for a psu of 90v the power in load be calculated in with losses of may be 11% p = v^2 / R so here its
6400 x 8 = 800w but the power ratings are rated as 450watts in 8 ohms... Im just doubtful on my calculations can anybody correct me in these psu calculations..
Your calculation math is fine but there are far more losses than what you calculated
Copper and iron PSUs drop around 20% if lightly loaded (as into 8 ohm loads) and around 30% if into 4 ohm loads (that's why 4 ohm power is not 2X 8 ohm power but only around 50% more)
You also lose about 4V per output transistor, 2 more per driver, 2 more for either the Vas or the CC one at the other end.
You also lose 2 to 3V per emitter ballast resistor.
Copper and iron PSUs drop around 20% if lightly loaded (as into 8 ohm loads) and around 30% if into 4 ohm loads (that's why 4 ohm power is not 2X 8 ohm power but only around 50% more)
You also lose about 4V per output transistor, 2 more per driver, 2 more for either the Vas or the CC one at the other end.
You also lose 2 to 3V per emitter ballast resistor.
My question is about the lower (stereo) power supply schematic. In all previous forum threads it's mentioned repeatedly that a center tapped transformer can only be connected to a single bridge,and here we have an example of a dual bridge with CT. I understand that this is a 'floating earth'. But why the aversion to this setup? Is there a disadvantage in using it?
Cheers
Cheers
My question is about the lower (stereo) power supply schematic. In all previous forum threads it's mentioned repeatedly that a center tapped transformer can only be connected to a single bridge,and here we have an example of a dual bridge with CT. I understand that this is a 'floating earth'. But why the aversion to this setup? Is there a disadvantage in using it?
Cheers
Actually - Good catch. Shouldn't work as posted. Relevant part with bad art. Two diodes in same orientation across transformer will not fly.
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Hi Steve,
Is there a way to make it fly with the two bridges?
If so,could you draw it please?
Thanks
If I knew a way I'd be famous - but I haven't. It's kinda like the 4 color map thing - after fiddling with it you become convinced that its true, but proving it is another can of worms (FWIW eventually proved with computers)
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