@6A3sUMMER - I said "well above 35kHz", if you do the math it's actually 39.8kHz, even in this surreal scenario...
Just 2 ideas; why would I use a flimsy driver for a difficult output stage and why would I use globak feedback when I don't need it?
Otherwise life sucks, we all agree on this... 🙂
Just 2 ideas; why would I use a flimsy driver for a difficult output stage and why would I use globak feedback when I don't need it?
Otherwise life sucks, we all agree on this... 🙂
45,
and Dorin Bodea,
Tacoma Narrows bridge (the original one, not the working pair we have now).
Versus:
The aging and working San Francisco Golden Gate Bridge (which went up in the same decade as the original Tacoma Narrows Bridge).
"All engineering solutions are equal, but some engineering solutions are more equal than others." - Me
Stolen and modified, with respectful reference to George Orwell's "Animal Farm".
Of course there are influences on engineering, coming from marketing, bean counters, and city mayors, etc.
Never let it be said that engineers are always the cause of a failed engineering project.
I do enjoy reading and analyzing both of your many posts.
Thanks!
and Dorin Bodea,
Tacoma Narrows bridge (the original one, not the working pair we have now).
Versus:
The aging and working San Francisco Golden Gate Bridge (which went up in the same decade as the original Tacoma Narrows Bridge).
"All engineering solutions are equal, but some engineering solutions are more equal than others." - Me
Stolen and modified, with respectful reference to George Orwell's "Animal Farm".
Of course there are influences on engineering, coming from marketing, bean counters, and city mayors, etc.
Never let it be said that engineers are always the cause of a failed engineering project.
I do enjoy reading and analyzing both of your many posts.
Thanks!
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@6A3sUMMER - Being on the old side of the poll I appreciate an apt philosophy now and then but a little wider cultural reference may help pointing out your view... I mean I know some things about Golden Gate but you probably know about Via Appia as much as I know about Tacoma bridge...
can't help miself posting these gems issued about 5 years ago here, on this very website 🙂
This is one of the links to the 1940 collapse of the original Tacoma Narrows Bridge:
Talpma Narrows bridge video
Talpma Narrows bridge video
@6A3sUMMER - more waves 🙂 ... exactly one of the xfmrs from my previous post, about 5 years ago...
Signal sweep 10Hz-50kHz, 2Vrms, "Iron Schmitt" phase splitter... 🙂 about 30Vrms OUT or 60 between phases
Signal sweep 10Hz-50kHz, 2Vrms, "Iron Schmitt" phase splitter... 🙂 about 30Vrms OUT or 60 between phases
and who can suggest a similar solution to this problem using solid-state elements?
@Pyka - sorry, I haven't visited this thread lately... I don't remember the exact operating point but was nothing unusual...
@Svytoslav - together with a good friend we've successfully simulated about 3-4 output stages using different SS devices, although I see more merits on keeping the amplifier all-tube. In all these simulations I've used ECC81/12AT7 tube class because I doubt a SS device will give better linearity - for more on this later
Meanwhile I've sourced several batches of cores and also some specialty magnet wires to advance in this project, stay tuned!
@Svytoslav - together with a good friend we've successfully simulated about 3-4 output stages using different SS devices, although I see more merits on keeping the amplifier all-tube. In all these simulations I've used ECC81/12AT7 tube class because I doubt a SS device will give better linearity - for more on this later
Meanwhile I've sourced several batches of cores and also some specialty magnet wires to advance in this project, stay tuned!
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Not right now, I have to restore from backup and rearrange a little, those are more than 3 years ago. I remember we use IRFP240 and later ECF20N20, in variants with and without output transformer, about +/-50V for output stage.
Meanwhile here's an all-tube application 🙂
yes, thank you! there are only 2 xfmrs in the schematic, clearly depicted in the description
Two further options; the two 32Ohm coils inserted at the CT to both lengthen the primary, and give two more accessible taps across the primary. Or...use the two of them for a screen FBK winding so g2 can run at a lower voltage( perhaps TV sweeps?).
Douglas
Douglas
- Douglas - first option you mentioned modifies of course the overall impedance (increasing the transformation factor too) and also moves the 33% ultraliniar tap up or down, depending where you insert these windings (2, 13 or 4, 11)
The second option I find it more useful, especially for those TV sweep tubes with huge voltage difference between Anode and G2 - yes, you can have a "safer" ultralinear connection this way. Thanks!
The second option I find it more useful, especially for those TV sweep tubes with huge voltage difference between Anode and G2 - yes, you can have a "safer" ultralinear connection this way. Thanks!